Question: Perforins are produced bya) Cytotoxic T cellsb) Suppressor T cellsc) Memory helper T cellsd) Plasma cellse) NK cells

Perforins

Perforins are hole forming proteins, cause transmembrane pores through which cytotoxic factors enter the cell and destroy it by apoptosis.
Perforins are produced by:

Cytotoxic T cells   → Robbin's 218
N.K. Cells → Ananthanarayan 126


Question: Traveller’s diarrhoea is most commonly caused by

Five types of E.coli include:
1. ETEC (enterotoxogenic E.coli)
2. EIEC (enteroinvasive E.coli)
3. EPEC (enteropathogenic E.coli)
4. EHEC (enterohemorrhagic E.coli)
5. EAEC (enteroaggregative E.coli)
Traveller's diarrhoea is most commonly caused by enterotoxogenic E.coli and then the other common organism responsible is S. dysenteriae. Intestinal Pathogenic E. Coli.


Question: 4 months old infant had respiratory distress.It was diagnosed as bronchiolitis. most common cause of this is

RSV is the m/c cause of lower respiratory tract infection below 1 year.


Question: Bacteria surviving alkaline media

Ans: c (Vibrio) Ref: Ananthanarayan, 7th ed, p. 305Culture characteristics of Vibrio: Strongly aerobic Temperature range 16 - 40deg C pH range 6.4 - 9.6 (Growth is better in alkaline medium, optimum pH is 8.2) MacConkey's agar - red colonies due to late fermentation of lactose. Blood agar - initially zone of greening later clears due to haemodigestion Gelatin stab culture: infundibuliform or napiform liquefaction


Question: Preisz Nocard bacilli is other name of

C. pseudotuberculosis also called preisz Nocard bacilli affect sheep and horse.


Question: Sunlight acts as sterilizing agent because


Question: Hepatocelluar carcinoma is caused by

Aflatoxin produced by A. flavus can cause Hepatoma, Hepatitis, Reye's Syndrome, Hepatocellular carcinoma.


Question: Neurotoxin of tetanus acts on


Question: Receptor of EBV is


Question: Lepra bacilli are mainly transmitted by

Ans. b (Droplets). (Ref. Ananthanarayan, Microbiology, 6th/pg.361)LEPRA BACILLI# Acid-fast bacilli, but less acid fast than TB bacilli.# H2SO4 used for decolorization of lepra bacilli (5%) is of less concentration than that for TB bacilli (25%).# Virchow lepra or foam cells in which globi of bacilli occur are large undifferentiated histiocytes.# Leprosy is exclusive human disease and patients are the only source of infection.# Very large numbers of bacilli are shed in nasal secretions (107/day), hence droplet is important mode of spread.# Mode of entry: Respiratory tract or through skin.# IP: 2-5years (few years to 30 days)# Not a highly communicable disease.# Prevalance in MH (1971 census) >> 5-8 cases per 1000 population.# Total no.of patients in India--4 million.


Question: Fogay's catheter is used for

Fogay catheter is like a ureteric catheter, with a balloon tip and is introduced until it is deemed to have passed the limit of the thrombus.The balloon is inflated and the catheter is withdrawn slowly with the clot.Ref: Bailey and love 27e pg- 955


Question: Most important risk factor for invasive aspergillosis are

All of above are risk factors. But most important is Glucocorticoid use.


Question: The most common complication associated with 'Total Parenteral Nutrition' is

The most common complication associated with TPN is a Catheter-related infectionTotal parenteral nutrition (TPN) is defined as the provision of all nutritional requirements by means of the intravenous route and without the use of the gastrointestinal tract.Parenteral nutrition is indicated when energy and protein needs cannot be met by the enteral administration of these substrates. The most frequent clinical indications relate to those patients who have undergone massive resection of the small intestine, who have an intestinal fistula or who have prolonged intestinal failure for other reasons.TPN can be administered either by a catheter inseed in the central vein or peripherally inseed central venous catheter (PICC) line or a conventional cannula (not preferred).Catheter-related sepsis occurs in 3-14% of patients. It may occur at the time of line inseion or afterwards by migration of skin bacteria along the external catheter surface.


Question: NIH swab is used to demonstrate

NIH (National Institute of health swab) is used in diagnosis of Enterobius.


Question: Tetanus toxin act by

The tetanus toxin specifically blocks synaptic inhibition in the spinal cord, presumably at inhibitory terminals that use glycine and GABA as neurotransmitters. The toxin acts pre-synaptically. The abolition of spinal inhibition causes uncontrolled spread pf impulses initiated anywhere in the central nervous system. This results in muscle rigidity and spasms due to the simultaneous contraction of agonists and antagonists, in the absence of reciprocal inhibition. Reference: Textbook of Microbiology; Anathanarayan and paniker's; 10th edition; Page no: 265


Question: Mechanism of action of tetanospasmin

Ans. is 'a' i.e., Inhibition of GABA release . Tetanospasmin blocks the release of inhibitory neurotransmitters (GABA and glycine) in brain-stem and spinal cord.


Question: A patients plasma has high levels of interferon beta. He most likely has an infection due to

Interferon beta is secreted during infection due to viruses. It is produced by fibroblasts. Types of interferons: Alpha Interferon (Leukocyte interferon) is produced by leucocytes. It has antiviral activity. Beta Interferon (Fibroblast interferon) is produced by fibroblasts and epithelial cells. It has antiviral activity. Gamma Interferon (Immune interferon) is produced by Tlymphocytes. It is concerned with immuno-modulatory and antiproliferative functions. Propeies of interferon Non-toxic Non -antigenic Species specific Inactivated by Protesases Belongs to Class of Cytokines Stable at pH over (2-10),except Gamma INF,which is labile at pH 2 Non-dialysable Non-sedimentable Reference: Ananthanarayan and Paniker&;s Textbook of Microbiology Tenth edition


Question: In mycetoma, pink to red granules are produced by

Actinomadura pelletri - Pink to red granules.
Madurella species - Black.
Nocardia - White to yellow.
Actinomadura madurae - White to yellow.


Question: Most sensitive test for HIV


Question: Pseudomonas aeruginosa

Cannot be destroyed at 55 degree at 1 hr.


Question: The urine sample of a patient has been sent to the laboratory to look for Leptospira. The specimen is to be screened by use of the


Question: Bile aesculin agar is the culture media for

Group D streptococcus has enteroccus feacalis / faecium.
Culture media - Bile aesculin agar.


Question: Malignant hydatid disease is caused by

Malignant hydatid disease is caused by Echinococcus Multi locularis.


Question: Maltese cross is Characteristic of

Maltese cross (ring forms arranged in tetrad) seen in Babesia.


Question: The most common form of anthrax in man is

In humans, approximately 95% of cases are cutaneous anthrax, and 5% are inhalation. Gastrointestinal anthrax is very rareRef: Jawetz, Melnick, & Adelberg's Medical Microbiology; Twenty-Seventh Edition; Chapter 11; Spore-Forming Gram-Positive Bacilli: Bacillus and Clostridium Species


Question: Differentiation of Neisseria gonorrhoeae and Neisseria meningitides is by


Question: Botulism is most commonly due to

Food-borne botulism is caused by the ingestion of the preformed toxin. The source of botulism is usually preserved food - meat and meat products. Reference: Textbook of Microbiology; Anathanarayan and paniker's; 10th edition; Page no: 269


Question: A 32 yr. old female is suffering from watery diarrhoea, hyponatremia and hypokalemia. Later it was diagnosed as cholera. The mechanism of action of heat labile toxin of Vibrio cholerae is

Enterotoxin -heat labile or cholera toxin acts by increasing CAMP which causes hypersecretion of water and electrolytes Ref: Textbook of Microbiology Baveja 5th ed Pg 279

Inhibiting the release of ACH from nerves

Inhibiting protein synthesis by inactivating EF 2


Question: Shigellosis is common in travelers to developing countries. Infection is commonly acquired through the

Organisms may be transmitted in a number of ways, such as by air, food, hands, sexual contact, and infected needles. However, for each disease or disease category, there is usually a portal of entry not always unique to the organism. The respiratory tract is a common portal of entry to such airborne organisms as M. tuberculosis. This is why respiratory precautions must be taken when patients are harboring viable M. tuberculosis.The gastrointestinal tract is usually infected from ingestion of contaminated food or water (Shigella, Salmonella, Campylobacter) or by an alteration of the normal microbial flora such as with C. difficile disease. The skin is a tough integument and intact, is resistant to most infectious organisms except those that may break down human skin. Breaches of the skin as by wounds, burns, and the like predispose patients to a variety of infections such as tetanus caused by wound contamination with spores of C. tetani, or direct infection by Staphylococcus, Streptococcus, or Gram-negative rods (such as Serratia or Pseudomonas).The genital tract may become infected either by sexual contact or by alteration of the genital environment as often occurs with yeast infections. Several bacteria such as N. gonorrhoeae, Chlamydia, and Treponema pallidum are transmitted by direct sexual contact with infected partners.


Question: Most common cause of UTI in a neonate is

Causative agents of UTI:Uncomplicated UTIComplicated UTI*E.coli *Klebsiella*Proteus species*Enterobacter*Staphylococcus saprophyticus*Enterococci *Chlamydia , Neisseria *Ureaplasma, Mycoplasma . Adenovirus *E.coli *Klebsiella*Proteus species*Serratia marcescens*Pseudomonas *Enterococci Staphylococci Ref:Harrison's infectious disease 2nd edition, p296


Question: Selenium sulphide is indicated for treating

Tinea Versicolor - antifungal can be used in localised lesions or shampoos containing ketoconazole, selenium sulphide, fluconazole can be used for extensive truncal lesions for 2 to 3 weeks. Reference: Textbook of Microbiology; Baveja; 4th edition .


Question: The following instrument is used to measure

Sling Psychrometer is used to measure both the dry bulb and wet bulb temperatures at the time. These temperatures are a measure of humidity content in the air.kata thermometer consisting principally of an alcohol thermometer used to measure air cooling.


Question: Best means of giving hepatitis B vaccine is

Ans. is 'c' i.e., Intramuscular Deltoid Prophalyxis against HBV . Both passive and active immunization are available for HBV infection prophylaxis. . Passive prophylaxis is by hepatitis B immune globulin (HBIG). . Active immunization is by recombinant hepatitis B vaccine. . These are two recombinant vaccines : Recombivax - HB Engerix - B Vaccine is given intramuscular into the deltoid or in infants into the anterolateral aspect of thigh. Gluteal injection is not recommended as it may result in poor immune response. . Three doses are given at 0, 1 and 6 months. . For pre exposure prophylaxis only hepatitis B vaccine is given. . For post exposure prophylaxis combination of HBIG and hepatitis B vaccine is recommended. For perinatal exposure single dose of HBIG at bih along with complete course of vaccination is recommended. First dose of vaccine should be given within 12 hours after bih.


Question: Colonies of M. tuberculosis appear in about

→ Generation time : 14-15 hours.
→ Colonies appear in about 2 weeks (may take upto 8 weeks).
→ Grows luxuriantly in culture (Eugonic) and addition of 0.5% glycerol improves its growth but it has no effect on M.Bovis, which is dysgonic (Grows sparsely).
→ Solid medium ⇒ Most widely employed for routine culture is Lowenstein-Jensen (LJ) medium without starch.


Question: Infection that causes acute febrile illness with jaundice and conjunctivitis is

Ref:- Harrisons T.B of internal medicine 19th edition; pg num:- 1143


Question: Acute haematogenous osteomyelitis is commonly caused by

A. i.e. (Staph, aureus) (197 - Ananthanaryan 7th)* Acute haematogenous osteomyelitis - causal organism is usually Staph, aureus, less often one of the other Gram positive cocci such as Streptococcus. Pyogenes or S. pneumoniae* Organism usually settles in the metaphysis most often in the proximal tibia or in the distal and proximal ends of the femur1. Staphylococcal toxic syndrome is due to Enterotoxin B & C**2. Pantone Valentine leucocitin is seen in - Staphylococci**3. The antibody marker in serum for Staph.endocarditis is - Antiteichoic acid**


Question: Burkitt's lymphoma is malignancy of

(A) (B-cell) (452-Baveja 4th) (566-Ananthanarayan 9th)Burkitt's lymphoma - a malignant neoplasm of B- lymphocytes (tumour of jaw)* EBV has affinity for lymphoid tissue. The virus especially affects B-lymphocytes. EBV infected B lymphocytes are transformed in such a way that they multiply continuously.B -cells* B. Cells are part Of adaptive immunity *** B. cells constitute 10% to 20% of the circulating peripheral lymphocytes* B. cells originate as well as mature in bone marrow (contrast to T- cells* IgM and IgD present on the surface of all native B. cells* After antigenic stimulation ,B. cells form plasma cells that secrete immunoglobulins *** B. cells bind to sheep erythrocytes coated with antibody and complement, forming EAC rosette* T. cells binds to sheep erythrocytes CD2 forming SRBC or E rosette* EB V is a polyclonar activator of B cells leads to the production of antibodied to host cells and viral proteins (AUTOIMMUNITY)During development T cells undergo both positive selection and negative selection, while B cells undergo only negative selectionEBV associated malignancies * Burkitt's lymphoma* Hodgkin's disease (mixed cellularity type)* T. cell lymphoma* Gastic carcinoma* Angiocentric nasal NK/T cell immunoproli ferative lesions* Angio-immuno-blastic lymphadenopathy* Nasopharyngeal carcinoma* T onsillar carcinoma* Thymoma* CNS lymphoma in AIDS and transplant recipientOther associated nonmalignant conditions* Oral hairy leukoplakia in AIDS Patients *** Chromic fatigue syndrome* X - linked lymphoproliferative syndrome (Duncan's syndrome).


Question: Selective medium for meningococcal infection is

Selective media for Neisseria meningitis is Thayer - Main media. Contain vancomycin, colistin and nystatin. These antimicrobials will suppress the growth of other organisms which inhibits the growth of Meningococci. Reference: Textbook of microbiology; Anathanarayan & paniker's 10th edition, pg no: 231


Question: Shadow casting is done in

Shadow casting - specimen is coated with a thin film of platinum or other heavy metals to increase the contrast of Electron microscope.


Question: Incubation period of gas gangrene is

The incubation period of gas gangrene may be as sho as seven hours or as long as six weeks after the wound was created, the average being 10-48 hrs with C.perfringens. Clostridium septicum: 2-3 days Clostridium novyi: 5-6 days Reference: Textbook of Microbiology; Anathanarayan and paniker's; 10th edition; Page no: 262


Question: a 70 year old women refused to take influenza vaccine , dveloped flu. death happend 1 week after pneumonia.most common cause of post influenza pneumonia

m/c organism in post influenza decondary pneumonia is staph .auerus Staphylococcus aureus pneumonia * S. aureus is an impoant cause of secondary bacterial pneumonia in children and healthy adults after viral respiratory illnesses (e.g., measles in children and influenza in both children and adults). * Staphylococcal pneumonia is associated with a high incidence of complications, such as lung abscess and empyema. * Staphylococcal pneumonia occurring in association with right-sided staphylococcal endocarditis is a serious complication of intravenous drug abuse. ref : ananthanaryana 9th ed


Question: Hybridoma technique is used to obtain

Hybridoma technique is used to produce Monoclonal antibodies (mAb) (Nobel prize Gwardee Kohler and Milstein): Hybridoma technique:- Monoclonal antibodies (mAb) are defined as the antibodies derived from a single clone of plasma cell; all having the same antigen specificity-- i.e. produced against a single epitope of an antigen. Principle- B cells fused with myeloma cells on HAT media (hypoxanthine aminopterine thymine media) Types of Monoclonal Antibodies: Mouse mAb contains 100% mouse derived proteins. The mouse proteins being foreign; can induce immune response in humans producing human anti-mouse antibody (HAMA); that in turn eliminate the mAb faster from the body. Chimeric mAb is prepared by recombination of 34% mouse proteins (variable region) and 66% human proteins (constant region). Humanized mAb: Here, only the antigen binding site is mouse derived (10%) and the remaining pa of mAb is human derived. Human mAb: 100% of amino acids are human derived. It is the best accepted mAb.

Immunology Pa 2 ( Hybridoma Technology, Complement Pathways, Interferon, Structure and Functions of Immune Cells )


Question: Following is the drug of choice for salmonella typhi acute infection

At 1st chloramphenicol is DOC Later ciprofloxacin Now resistance developed to both so cephalosporins like cefixime are the DOC Ref: Textbook of Microbiology Baveja 5th ed Pg 230


Question: Infective form of Ascaris is

Parasitic Infections Transmitted by OvaEnterobius vermicularis (pinworm)Ascaris lumbricoides (roundworm)Toxocara canis (visceral larva migrans)Trichuris trichiura (whipworm)Echinococcus granulosus/multilocularisTaenia solium (cysticercosis)All others are transmitted in larval stage Ref : Paniker's textbook of Medical Parasitology Pgno : 196-197


Question: Pontine valentine toxin produced by Staphylococcus is an example for

Pontine valentine toxin of Staphylococcus superantigen which produces lot of stimulation producing massive release of antibodies Ref: Textbook of Microbiology Baveja 5th ed Pg 112


Question: Shelf life of CPD blood is

CPD - shelf life of blood stored in CPD stored at 2 to 4C is 21 days CPD:Citric acid Phosphate dextrose


Question: Botulinum toxin acts on

It acts by blocking the production and release of acetylcholine at synapses and NMJ. Thus affects the parasympathetic system. Reference: Textbook of Microbiology; Anathanarayan and paniker's; 10th edition; Page no: 269


Question: The test having the fastest lab processing time for karyotype assessment is

Amniocentesis, cordocentesis, cystic hygroma aspiration, and chorionic villus sampling are techniques for obtaining fetal tissues that are amenable to cytogenetic analysis.Amniotic fluid cells require tissue culture to obtain adequate cell numbers for analysis.Chorionic villi can be harvested directly for extremely rapid diagnosis or can be cultured for higher banding (increased detail).


Question: Bacterial count in doudenum

Ans. is 'a' i.e., 105 per gram In GIT of an adult : Duodenum - -4 103 - 106 bacteria per gram. Jejunum and proximal ileum - 10' - 108 bacteria per gram Lower ileum and cecum - 108 - 1010 bacteria per gram Colon and rectum - 10" - 1012 bacteria per gram Colon and rectum have maximum number of bacteria and most of them (96-99%) are anaerobes : Anaerobic streptococci Clostridia Anaerobic lactobacilli Bacteroides


Question: A Cerebrospinal fluid of a 2 years old child has been sent to the laboratory to detect the presence of capsulated yeast. The staining technique most commonly employed for the purpose is


Question: Causative microorganism of chromoblastomycosis is

Chromoblastomycosis or verrucous dermatitis is caused by cladophialophora, phialophora, exophiala, F.pedrosoi, F.compacta. Histoplasma causes histoplasmosis. Sporothrix causes sporotrichosis. Blastomyces causes blastomycosis. Ref: Textbook of Microbiology, Ananthanarayan and Paniker; 9th edition .


Question: A sporangium contains

Sexual spores are of 4 types - oospore, ascospore, zygospore and basidiospore. Ascospore produced by ascomycetes. Asexual spores are of 2 type - vegetative and aerial spores. Vegetative - blastospores, ahrospores and chlamydospores. Aerial - conidiospores, microconidia, macroconidia , sporangiospores. Reference: Textbook of Microbiology; Baveja; 4th edition


Question: A 42 yr old male from srilanka presented with multiple polyps in nose .the causative agent might be

Rhinosporidiosis -common in India, Srilanka .pt presents with multiple friable polyps in nose, mouth or eye. It is a chronic granulomatous disease Ref: Baveja 5th ed pg: 552


Question: Immunoglobulin crossing placenta is


Question: Von magnus phenomenon is

Commonly hemagglutinin titre α Infectivity but in Von-Magnus phenomenon - High hemagglutinin titre, Low infectivity due to mutation in virulent gone.

High hemagglutinin titre, low infectivity

High hemagglutinin titre, high infectivity

Low hemagglutinin titre, low infectivity

Low hemagglutinin titre, High infectivity


Question: Culture media for peussis is

Culture media for Bordetella peussis is Bordet Gengou media or Regan Lowe media. Bordet Gengou media- after incubation for 48-72 hours- colonies resemble 'bisected pearls' or 'mercury drops' LJ media For M. tuberculosis Wilson & Blair medium For Salmonella typhi

Systemic Bacteriology (Gram Positive Bacilli, Gram Negative Bacilli)


Question: The fibular collateral ligament is the continuation of

Fibular collateral ligament is a degenerated pa of Peroneus Longus muscle.Oblique popliteal ligament is a continuation of semimembranosus muscle. It lies in the floor of the popliteal fossa.The tibial collateral ligament represents the degenerated pa of Adductor Magnus.The sacrotuberous ligament represents the degenerated pa of the long head of biceps femoris.Sacrospinous ligament represents the degenerated pa of Coccygeus muscle.


Question: The medium that is most ideal for antibiotic sensitivity testing of bacterial isolates is

Nutrient agar is good for antibiotic sensitivity testing Muller Hinton medium for testing aerobes and facultative anaerobes Ref: Textbook of Microbiology Baveja 4th ed Pg 628


Question: Avian influenza HA viruses bind

(D) Alpha 2-6 sialic acid receptors# Genetic factors in distinguishing between "human flu viruses" and "avian flu viruses" include:> PB2: (RNA polymerase): Amino acid (or residue) position 627 in the PB2 protein encoded by the PB2 RNAgene. Until H5N1, all known avian influenza viruses had a Glu at position 627, while all human influenza viruses had a Lys.> HA: (hemagglutinin): Avian influenza HA viruses bind alpha 2-3 sialic acid receptors, while human influenza HA viruses bind alpha 2-6 sialic acid receptors. Swine influenza viruses have the ability to bind both types of sialic acid receptors. Hemagglutinin is the major antigen of the virus against which neutralizing antibodies are produced, and influenza virus epidemics are associated with changes in its antigenic structure. This was originally derived from pigs, and should technically be referred to as "pig flu".


Question: Candida is most often implicated in causation of

Candida infection causes mucosal lesion like vaginitis and oral thrush. oral thrush found commonly in bottle-fed infants and aged and debilitated. This condition is characterised by creamy white patches appear on the tongue and buccal mucosa following removal, this leaves a red oozing surface. Tinea capitis is caused by dermatophytes. Ref: Textbook of Microbiology, Ananthanarayan and Paniker; 9th edition


Question: Natural killer cells

Natural Killer CellsThe function of NK cells is to destroy irreversibly stressed and abnormal cells, such as virus-infected cells and tumor cells. NK cells make up approximately 5% to 10% of peripheral blood lymphocytes. They do not express TCRs or Ig.NK cells are endowed with the ability to kill a variety of virus-infected cells and tumor cells, without prior exposure to or activation by these microbes or tumors.Two cell surface molecules, CD16 and CD56, are commonly used to identify NK cells. CD16 is an Fc receptor for IgG, and it confers on NK cells the ability to lyse IgG-coated target cells. This phenomenon is known as antibody-dependent cell-mediated cytotoxicity (ADCC). The function of CD56 isnot known.Ref: Robbins and Cotran Pathologic Basis of Disease; 9th edition; Chapter 6; Diseases of the Immune System

Requires previous antigen exposure for activation


Question: Uterine bleeding at 12 weeks gestation without any cervical dilation is an indication of

Bleeding occurs in about 30 to 40%of human gestations before 20 weeks of pregnancy, with about half of these pregnancies ending in spontaneous aboion. A threatened aboion takes place when this uterine bleeding occurs without any cervical dilation or effacement


Question: Germ tube test is used in the diagnosis of

Candida albicans has the ability to form germ tubes within 2hrs when incubated in human serum at 37C. Ref: Textbook of Microbiology, Ananthanarayan and Paniker; 9th edition


Question: Stain used to detect degenerated fungi in tissues

PAS (Periodic acid schiff) & GMS (Gomori methanamine silver) is used to detect degenerated fungi in tissues.


Question: A farmer has an ulcer on a leg with indurated margin and multiple sinuses with discharging black granules. The likely diagnosis is

Actinomycotic mycetoma - white to yellow granules and filaments are thin. Mycotic mycetoma - black granules and filaments are stout. Ref: Textbook of Microbiology, Ananthanarayan and Paniker; 9th edition


Question: "Accole forms" are seen in

Ans. a P. falciparum (paniker parasitology 7th ed., p 80) In P. falciparum multiple rings with "accole" forms are seen.CharacteristicsP. FalciparumP. VivaxP. OvaleP. MalariaeAsexual parasitesUsually only fine blue ring forms (some resembling stereo headsets) are seen Parasitemia level may exceed 2%.Irregular, large, fairly thick rings become highly pleomorphic as the. parasite grows. Parasitemia level is low.Regular, dense ring enlarges to compact, blue, mature trophozoite (rectangular or band-form). Parasitemia level is low.Dense, thick rings mature to dense, round trophozoites. Parasitemia level is lowSchizontsRare in peripheral blood; 8-32 merozoites, dark brown-black pigmentCommon; 12-18 merozoites, orange-brown pigment8-14 merozoites, brown or black pigment8-10 merozoites, dark brown or black pigmentGametocytesBanana-shaped; male: light blue; female: darker blue; a few scattered blue-black pigment granules in cytoplasmRound or oval; male: round, pale blue; female: oval, dark blue; triangular nucleus, a few orange pigment granulesLarge, round, dense, and blue (like P. malariae), but prominent James's dots; brown pigmentLarge, oval; male: pale blue; female: dense blue; large black pigment granulesRBC changesRBCs are normal in size. As the parasite matures, the RBC cytoplasm becomes pale, the cells become crenated, and a few small red dots may appear over the cytoplasm (Maurer's clefts).RBCs are enlarged. Pale red Schuffner's dots increase in number as the parasite matures.RBCs become oval with tufted ends. Red James's dots are prominent.RBCs are normal in size and shape. No red dots are seen.


Question: Reynolds Braude phenomenon seen in

Germ tube test also called Reynolds Braude Phenomenon, is a specific test for C. Albicans.


Question: CD4 count in normal healthy adult is


Question: IgG has subclasses


Question: Hypercalcemia would not be expected to occur as a result of

Hypercalcemia often is associated with malignancies and is due either to skeletal metastasis or to a humoral substance secreted by a tumour.Hypercalcemia accompanying sarcoidosis appears to be due to enhanced synthesis of vitamin D.Thiazide diuretics cause hypercalcemia by decreasing the urinary clearance of calcium. Lithium may cause a mild hypercalcemia by elevating plasma parathormone levels.Calcium levels in persons with hypothyroidism are either normal or low as a result of the decreased bone turnover.


Question: Human is the only reservoir for

Ans. is 'c' i.e., Measles Reservoir of infection may be :? Human reservoir Non - Human reservoir Animal or bird Non - living things (e.g. - soil) Most impoant reservoir or source of infection for human is man itself. However, most of the infections have nonhuman reservoir also. There are some infections, which have only human reservoir, i.e. they do not have non-human reservoir. Such infections are Measles, Typhoid (S. typhi), Syphilis (T pallidum), Gonorrhoea (gonococci), Loose borne relapsing fever (Borrelia recurrents), cholera (V cholerae).


Question: Most fungi of medical importance belongs to


Question: Ritter&;s disease is caused by

Exfoliative (Epidermolytic) toxin is responsible for the staphylococcal scalded skin syndrome. It is an exfoliative skin disease in which the outer layer of the epidermis gets separated from the underlying tissues. The severe form of SSSS syndrome is known as Ritter's disease in the newborn and toxic epidermal necrolysis in older patients. Milder forms are pemphigus neonatorum and bullous impetigo. Ref: Textbook of Microbiology; Ananthanarayanan and Panicker; 10th Edition; Page No: 204


Question: Influenza is caused by


Question: The Most common organism causing meningitis in a patient with AIDS

(C) Cryptococcus neoformans # Cryptococcal meningitis is the most serious type of infection and can resemble tuberculous or other chronic types of meningf.is.> Its onset is insidious and the course slow and progressive.> It is often seen in AIDS.


Question: Germ tube test is done for

Germ tube test / Reynold braude phenomenon - specific test for Candida albicans Colonies are mixed with human or sheep serum & incubated for 2 hours . Wet mount preparation is examined under microscope. Germ tubes are formed , describe as long tube like projections extending from yeast cells.


Question: Autoclaving is done in

Moist head sterilization - Pasteurization,water bath,inspissation < 100 degree C Boiling,Steaming,Tyndallization = 100 degree C Autoclave >100 degree C Most commonly used sterilization condition for autoclave is 121 degree C for 15 min at pressure of 15 pounds.

General Microbiology Pa-2 and Pa-3 (Sterilization and Bacterial Genetics)


Question: A child has a respiratory infection with a membrane over Peritonsillar area. A swab was taken from the local area. The appropriate media for culture is

A common cause of respiratory infection with a membrane over the tonsil is Corynebacterium diphtheriae. Media appropriate for culture is Tellurite blood agar: Tellurite inhibits the growth of most other bacteria acting as a selective agent for diphtheria bacilli. Diphtheria bacilli reduce Tellurite to metallic tellurium which is incorporated in the colonies giving them a grey or black color. Reference: Textbook of Microbiology; Anathanarayan and panicker's; 10th edition; Page no: 242


Question: Most of the cases of Listeria are due to serovar

Ans. is 'c' i.e., 4b LISTEROSIS . Mode of transmission; Food borne ---> Most common (most cases are due to serotype 4b) Nosocomial --> In late onset neonatal infection. . Foods implicated in infection include contaminated colesaw, pasteurized milk, soft cheese, pate, ready to eat turkey and pork productes, hot dogs, butter, prepared salads, undercooked chicken.


Question: Transfer of drug resistance is staphylococcus is by

Beta-lactamase-mediated: this is mediated through the production of beta-lactamase or penicillinase, which inactivates penicillin by splitting the beta-lactam ring. these are inducible enzymes which are plasmid-mediated.they can be transmitted by transduction or conjugation. Ref: Textbook of Microbiology; Ananthanarayanan and Panicker; Tenth Edition; Page No: 202


Question: Neisseria infection is associated with

Meningitis and meningococcemia are caused by Neisseria meningitides Fulminant meningococcemia caused by Neisseria meningitidis is called Waterhouse Friderichsen syndrome. Fatal condition - characterized by shock, disseminated intravascular coagulation and multisystem failure. Meningococcal disease is ored by the deficiency of terminal complement components ( C5 - C9). Reference: Textbook of Microbiology; Anathanarayan and panicker's; 10th edition; Page no: 232


Question: Maltess cross seen on polarizing microscopy in

Ans. is 'a' i.e., Cryptococcus neoformans Maltese cross pattern under palarized light is seen in :- Babesia, Cryptococcus, Aspergillus nidulans, starch granules and lipid (cholesterol) droplets. "Fungal ball due to Aspergillus nidulans have a propensity to produce pale staining thick walled non-ble null cells that show maltese cross bifringence when examined under polarized light". "On polarized light the spores in cryptococcus give maltese cross appearance". - Atals of deep mycosis "Babesia microti is associated with maltese cross forms and ring forms". - Barbara J. Bain "Starch granules and fat (cholesterol) droplets produce maltese cross pattern in polarized light".


Question: A patient with a peptic ulcer was admitted to the hospital and a gastric biopsy was performed. The tissue was cultured on chocolate agar incubated in a microaerophilic environment at 37degC for 5 to 7 days. At 5 days of incubation, colonies appeared on the plate and were curved, Gram negative rods, oxidase positive. The most likely identity of this organism is

This organism is readily isolated from gastric biopsies but not from stomach contents. It is like Campylobacter species and grows on chocolate agar at 37degC in the same microaerophilic environment suitable for C. jejuni (Campy-Pak or anaerobic jar without the catalyst). H. pylori, however, grows more slowly than C. jejuni, requiring 5 to 7 days incubation. C. jejuni grows optimally at 42degC, not 37degC, as does H. pylori.

Systemic Bacteriology (Haemophilus, Yersinia, Spirochaetes, Ricketssia, Chlamydia, Mycoplasma and Miscellaneous Bacteria)


Question: Stauffer syndrome is related to

Nonmetastatic nephrogenic hepatic dysfunction syndrome (Stauffer&;s syndrome) is a unique paraneoplastic manifestation of renal cell carcinoma that is usually manifested as anicteric cholestasis.It is characterized by elevated alkaline phosphatase, erythrocyte sedimentation rate, a-2-globulin, and g-glutamyl transferase, thrombocytosis, prolongation of prothrombin time, and hepatosplenomegaly, in the absence of hepatic metastasis and jaundice.Renal Cell Carcinoma :Also known as Hypernephroma/Grawitz tumourRisk factors :Cigarette smoking (strongest association)Tuberous sclerosisVon Hippel Lindau syndromeAdult polycystic kidney diseaseAcquired cystic disease of kidney associated with end-stage renal disease


Question: Floppy baby syndrome is caused by

Infant botulism: This is a toxico-infection.Cl.botulinum spores are ingested in food, get established in the gut and there produce the toxin. Cases occur in infants below six months. Manifestations are constipation, poor feeding, lethargy, weakness, weak or altered cry, floppiness and loss of head control.Honey has been incriminated as a likely food item through which bacillus enters the gut.Ref: Ananthanarayan; 7th edition; Page no: 264


Question: Treatment of choice for the annular pancreas is

Annular pancreas is the most common congenital malformation of the pancreas in association with duodenal atresia.Two types of the annular pancreas are recognized. (1) Extramural - causing high gastrointestinal (duodenal) obstruction; vomiting is the most common presenting symptom (2) Intramural - producing duodenal ulcerationAssociated with polyhydramnios, Down syndrome.ERCP is the most impoant procedure to find the characteristic features and establish the therapeutic strategy in cases of annular pancreas. Division of annular pancreas is not recommended because of the risk of damage to the major duct.


Question: Reverse transcriptase of HBV is coded on

P is the large gene having 3 enzymatic activities

DNA polymerase activity
Reverse transcriptase activity
RNase H activity.


Question: The Norwalk virus is a

Viral gastroenteritis:FamilyVirusViral genomeReoviridaeRotavirusdsRNACalciviridaeNorovirus/Norwalk virusSapovirusss(+)RNAAdenoviridaeAdenovirusdsDNAAstroviridaeAstrovirusss(+)RNACoronaviridaeCoronavirusTorovirusss(+)RNAPicornaviridaeAichi virusss(+)RNAPicobirnaviridaePicobirnavirusdsRNAParvoviridaeBocavirusssDNAParamyxoviridaeHendra virusNipah v irusSs(-)RNA(Ref: Ananthanarayan 9th edition, 562)


Question: Cyst and trophozite in stool


Question: Blood agar is an example of

Enriched media: In these media, substances such as blood, serum, or egg are added to a basal medium. They are used to grow bacteria which are more exacting in their nutritional needs. Examples: Blood agar; Chocolate agar and egg media. Ref : Ananthanarayana textbook of Microbiology 9th edition Pgno : 40


Question: Macrophages are major source of

Macrophages are major source of IL - 1, IL - 8, IL - 12.


Question: The reaction between antibody and solouble antigen is demonstrated by

When a soluble antigen reacts with its antibody in the presence of electrolytes (NaCl) at an optimal temperature and pH, the antigen-antibody complex forms an insoluble precipitate and it is called precipitation.
The precipitate usually sediments at the bottom of the tube.
Precipitation may occur in liquid media or in gels such as agar, agarose or polyacrylamide

Ref : textbook of microbiology, C P Baveja 5th edition pg no:106


Question: Rapid examination of tubercle bacilli is possible with

Auramine rhodamine: When several smears are to be examined daily, it is more convenient to use fluorescent microscopy. Smears are stained with auramine phenol or auramine rhodamine fluorescent dyes and examined under ultraviolet illumination or where the source is LED. Bacilli appear as bright rods against the dark background. Because of the contrast, the bacilli can be seen even under the high dry objective, enabling large areas of the smear to be screened rapidly. Ref: Textbook of microbiology; Ananthanarayan and paniker's; 10th edition; Pg:358


Question: Nocardia can be differentiated from other Actinomyces by

Actinomyces - on ZN staining- central pa as non-acid fast surrounded by acid-fast clubs( antigen-antibody complex ). Nocardia- on ZN staining - acid-fast. Nocardia species are aerobic. Reference: Textbook of Microbiology; Ananthanarayan and paniker's; 10th edition; Pg: 398


Question:
Rapid evaluation of fungal hyphae/spores can be
achieved with


Question: Drug of choice for carriers of diphtheria is

Corynebacterium diphtheriae is sensitive to Penicillin and can be cleared from the throat within a few days by Penicillin treatment. Erythromycin is more active than Penicillin in the treatment of carriers. Reference: Textbook of Microbiology; Anathanarayan and panicker's; 10th edition; Page no: 245


Question: Cowdry type A inclusion bodies are characteristic of

Cytology and Histology: In some instances, viruses produce specific cytologic changes in infected host tissues that aid in diagnosis. Examples include specific intranuclear inclusions seen in neuronal infections due to herpes simplex (Cowdry type A-bodies) and due to intracytoplasmic inclusions in rabies (Negri bodies), and cell fusion, which results in multinucleated epithelial giant cells (eg, measles and varicella zoster).Ref: Sherris microbiology; 6th edition; Page no: 69


Question: The most common organism responsible for gas gangrene is

C.perfringens is the predominant agent causing gas gangrene. It may occur as the sole causative agent but is more commonly seen in association with other clostridia as well as non-clostridial anaerobes. More commonly all clostridial infections do not result in gas gangrene. More commonly, they lead only to wound contamination or anaerobic cellulitis. It is the only when muscle tissue is invaded that gas gangrene results. Reference: Textbook of Microbiology; Anathanarayan and paniker's; 10th edition; Page no: 259


Question: Organism implicated in Cellulitis following animal bites is

Pasteurella multocidaDistinguishing Features: small gram-negative rods; facultative anaerobic rodsReservoir: mouths of many animals, especially cats and dogsTransmission: animal bites; paicularly from cat bitesPathogenesis: endotoxin, capsule; spreads rapidly within the skin, no exotoxins knownDisease: cellulitis with lymphadenitis (rapidly spreading wound infections, frequently polymicrobial infections)Diagnosis: rarely cultured because routine prophylaxis is commonTreatment: amoxicillin/clavulanate for cat bites; resistant to macrolidesPrevention: amoxicillin/clavulanate is standard prophylaxis and treatment for most bites (including human), along with a thorough cleaningOther organisms associated with animal bites:Eikenella corrodens: human bites or fist fight injuriesCapnocytophaga canimorsus: dog bite woundsBaonella henselae: Cats and dogs/ bites, scratches, fleasRef: Jawetz; 27th edition; Page no: 278


Question: Soluble components of complement system account for about


Question: Diphtheria toxin acts by

The diphtheria toxin acts by inhibiting protein synthesis. Specifically, a fragment B heparin binding and fragment A inhibits polypeptide chain elongation in the presence of nicotinamide adenine dinucleotide by inactivating the elongation factor EF-2. It has a special affinity for ceain tissues such as the myocardium, adrenals and nerve endings. Reference: Textbook of Microbiology; Anathanarayan and panicker's; 10th edition; Page no: 240


Question: A child presents with a white patch over the tonsils, diagnosis is best made by culture in

White patch over the tonsil is suggestive of infection with cCorynebacteriumdiphtheriae. It can be confirmed by culture in Tellurite blood agar. Tellurite inhibits the growth of most other bacteria acting as a selective agent for diphtheria bacilli. Diphtheria bacilli reduce Tellurite to metallic tellurium which incorporates into colonies giving them a grey or black color. Reference: Textbook of Microbiology; Anathanarayan and panicker's; 10th edition; Page no: 242


Question: Tetanus is caused by

Tetanus is caused by Clostridium tetani. It produces two toxins: tetanolysin and tetanospasmin. Tetanospasmin is responsible for tetanus. Tetanus is characterized by tonic muscular spasms usually commencing at the site of infection later become generalized, involving the whole of the somatic muscular system. Reference: Textbook of Microbiology; Anathanarayan and paniker's; 10th edition; Page no: 265


Question: The operating temperature in an ethylene oxide sterilization during warm cycle is


Question: Poiseuille's Hagen law is

Poiseuille-Hagen FormulaThe relation between the flow in a long narrow tube, the viscosity of the fluid, and the radius of the tube is expressed mathematically in the Poiseuille-Hagen formula:F = (PA-PB) X (dj/8) X (1/dj) X (r4/L)whereF = FlowPA-PB = Pressure difference between the two ends of the tubedj = Viscosityr = Radius of tubeL = Length of tube


Question: Ehrlich phenomenon is seen in

The difference between the amount of diphtheria toxin that will exactly neutralize one unit of antitoxin and that which, added to one unit of antitoxin, will leave one lethal dose free is greater than one lethal dose of toxin; i.e., it is necessary to add more than one lethal dose of toxin to a neutral mixture of toxin and antitoxin to make the mixture lethal (the basis of the L+ dose). Reference: Textbook of Microbiology; Anathanarayan and panicker's; 9th edition


Question: Progressive multifocal leukoencephalopathy is caused by

(D) Papova virus # Progressive multifocal leukoencephalopathy is a viral encephalitis caused by a polyomavirus (Papova virus or JC virus, totally unrelated to Creutzfeldt-Jakob disease) because the virus preferentially infects oligodendrocytes, demyelination is its principal pathologic effect.> Progressive multifocal leukoencephalopathy (PML), also known as progressive multifocal leukoencephalitis, is a rare and usually fatal viral disease that is characterized by progressive damage (-pathy) or inflammation (-His) of the white matter (leuko-) of the brain (-encephalo-) at multiple locations (multifocal).> It occurs almost exclusively in people with severe immune deficiency, e.g. transplant patients on immunosuppressive medications, or AIDS patients.> The cause of PML is a type of polyomavirus called the JC virus (JCV).


Question: Commonest cause of nosocomial infection is

According to the CDC, the most common pathogens that cause nosocomial infections are Staphylococcus aureus, Pseudomonas aeruginosa, and E. coli. Some of the common nosocomial infections are urinary tract infections, respiratory pneumonia, surgical site wound infections, bacteremia, gastrointestinal and skin infections. Ref: Ananthanarayana & panikers 10th edition


Question: Figure of 8 appearance is seen in


Question: Most common complication of mumps is

Ans. is 'a' i.e., Orchitis and oophritis(Ref: Harrison, 18th/e, 1609; 19th/e, p. 1298)* Epididymoorchitis is the most common manifestation of mumps among postpubertal males (15-30%).* Aseptic meningitis (<10%), which may develop before, during, after, or in the absence of parotitis.* Oophritis (5%) and Pancreatitis (4%).


Question: Stain for treponema


Question: A patient presented with fever, cervical lymphadenopathy and night sweats four weeks after unprotected sexual contact. Next investigation

Ref: PubMed* This is a possible suspicion of HIV infection.* p24 antigen is a viral protein that makes up most of the viral core.* Serum concentrations of p24 antigen are high in the first few weeks after infection; tests sensitive to p24 antigen are therefore useful for diagnosing very early infection when antibody levels are still low.


Question: An idiotype is characterized by

Idiotypes are antigenic determinants that appear only on the Fab fragments of antibodies and appear to be localized at the ligand-binding site; thus, anti-idiotype antisera may block reactions with the appropriate hapten. The carbohydrate side chains of immunoglobulins are relatively nonimmunogenic. New determinants may be exposed after papain cleavage of immunoglobulins, but these determinants are not included in the classification of the native molecule. Reference: Ananthanarayan and Paniker&;s Textbook of Microbiology Tenth edition

Determinant exposed after papain cleavage to an F(ab')2 fragment

Determinant from one clone of cells and probably located close to the antigenbinding site of the immunoglobulin

Determinant inherited in a Mendelian fashion and recognized by crossimmunization of individuals in a species

Heavy-chain determinant recognized by heterologous antisera


Question: In a population of 5000, on 1st January, total cases of myopia were 500. Till 31st December, 90 new cases were found. Calculate the incidence of myopia per 100

Incidence = Number of new cases of a specified disease during a given time period x 100 Population at risk during that periodPopulation at risk = 5000-500= 4500Incidence of myopia during the year in the population would be - 90 x 100 = 2 per 100 4500


Question: Treatment for streptococcal necrotizing fasciitis is

Streptococcal subcutaneous infections range from cellulitis to necrotizing fasciitis. Necrotizing fasciitis is more commonly caused by mixed aerobic and anaerobic bacterial infections, but some strains(M types 1 and 3 forming pyrogenic exotoxin A) may alone be responsible. These strains have earned the name "flesh-eating bacteria". Though the isolates are penicillin sensitive in vitro, treatment with penicillin may not be effective. Vancomycin is the drug of choice in life-threatening infections. Reference: Textbook of Microbiology; Anathanarayan and paniker's; 10th edition; Page no: 214


Question: Indicator for the outbreak of Plague epidemic is

Cheopis index: It is an average no of X.cheopis per rat. It is a specific flea index. If this index is more than 1, it is regarded as indicative of potential explosiveness of the situation, should a plague outbreak occur


Question: Central macular fixation develops at

The critical period of developed of fixation reflex is 5-6 months of age.This is the reason why unilateral cataracts in children should be operated early.Remember - Binocular vision develops at 5-6 years.


Question: The most common organism among the following that causes acute meningitis in an AIDS patient is

Cryptococcosis occurs worldwide since the fungus is soil saprophyte and is the commonest systemic mycosis in India. Cryptococcal meningitis is the most serious type of cryptococcal infection seen in AIDS patients compared to others. Ref: Textbook of Microbiology, Ananthanarayan and Paniker; 9th edition


Question: Sterilization of media containing serum is by

Autoclave is used for sterlizing : surgical instruments culture media Plastic containers /Pipettes/Tubes . Gloves,aprons, dressing suture material except catgut Membrane/Micropore filter Membrane filters remove microorganisms by screening them out as they have less pore size than bacteria Made up with cellulose acetate, cellulose nitrate, polycarbonate etc. Serum , Trypsin, growth factors, proteins, amino acids, vitamins and hormones are thermolabile and may decompose during autoclaving, so must be sterilized by Membrane filters. Ionising radiations: 1. Examples include, X-rays, gamma rays (from Cobalt 60 source), and cosmic rays. 2. Mechanism: It causes breakage of DNA without temperature rise (hence called as cold sterilization). It is used for: Disposable plastics, e.g. rubber or plastic syringes, infusion sets and catheters. Catgut sutures, bone and tissue grafts and adhesive dressings, antibiotics and hormones. Centrifugation is not a method of sterilization.

General Microbiology Pa-2 and Pa-3 (Sterilization and Bacterial Genetics)


Question: The predominant isoenzyme of LDH in the cardiac muscle is

Lactate dehydrogenase (LDH) is a tetrameric enzyme consisting of two monomer types: H (for hea) and M (for muscle) that combine to yield five LDH isozymes: HHHH (I1), HHHM (I2), HHMM (I3), HMMM (I4), and MMMM (I5).Isozyme I1 predominates in hea tissue and isozyme I5 in the liver. Thus, when LDH levels rise in blood plasma, the identity of the injured tissue can be inferred from its characteristic pattern of LDH isozymes.In normal plasma LDH-2 is more in concentration than LDH - 1.In myocardial infarction level of LDH - 1 increases and this leads to the altered ratio of LDH.It means LDH - 1 > LDH - 2.This altered ratio of the LDH is known as a flipped pattern.Ref: Harper; 30th edition; Page no 69


Question: Speed of rabies virus progress in axon is

Speed of rabies virus progress in axon is 250 mm/day.


Question: PML is caused by

(B) Papova virus # Human papova virus has been isolated from a number of patients with impaired immunity> J.C. virus one type of papova virus which is isolated from patient with : HIV Hodgkin lymphoma Progressive Multi focal leukoencephalopathy (PML). Progressive multifocal leukoencephalopathy (PML) is a rare and usually fatal viral disease characterized by progressive damage or inflammation of the white matter of the brain at multiple locations. It is caused by the JC virus, which is normally present and kept under control by the immune system. JC virus is harmless except in cases of weakened immune systems. PML occurs almost exclusively in patients with severe immune deficiency, most commonly among patients with acquired immune deficiency syndrome (AIDS), but people on chronic immunosuppressive medications including chemotherapy are also at increased risk of PML, such as patients with transplants, Hodgkin's Lymphoma, multiple sclerosis, psoriasis and other autoimmune diseases.


Question: Most common fungal infection in febrile neutropenia

Most common fungal infection in Febrile Neutropenia / Immunocompromised state is Candidiasis Most likely the infection is caused by candida albicans which is the most pathogenic strain of candida


Question: This is caused by

This is a picture of Cutaneous leishmaniasis (oriental sore), the most common form of leishmaniasisThree distinct patterns of old world cutaneous leishmaniasis have been recognized.1) The anthroponotic urban type causing painless dry ulcerating lesions, leading to disfiguring scars, caused by the species L. tropica. It begins as a raised papule, which grows into a nodule that ulcerates over some weeks.2) The zoonotic rural type causing moist ulcers which are inflamed, often multiple, caused by L. major.3)The non-ulcerative and often diffuse lesions caused by L. aethiopica and seen in the highlands of Ethiopia and Kenya are known as diffuse cutaneous leishmaniasis.Panicker parasitology pg: 60


Question: Colpitis macularis is seen in

Colpitis macularis / Strawberry vagina seen in 2 % cases in Trichomons vaginalis infection.


Question: Causative organism of HUS is

Hemolytic-uremic syndrome (HUS) often occurs after a gastrointestinal infection with E coli bacteria (Escherichia coli O157:H7). However, the condition has also been linked to other gastrointestinal infections, including shigella and salmonella.Shigella spp:General characteristicsCultural characteristics*Gram negative bacilli*Non motile, non-capsulated *Selective media - DCA agar, XLD agar, SS agar*Enrichment broth - Gram-negative broth, Selenite F broth, Tetrathionate brothBiochemical reactionsVirulence factors *Ferment mannitol except for S.dysenteriae*Catalase positivity except S.dysenteriae type 1*Lactose non-fermenters except S.sonnei (Late lactose fermenter)*Invasiveness of Shigella - Virulence marker antigen*Endotoxin - LPS*Heat labile exotoxin (Shiga toxin) - Chromosome coded toxin produces neurotoxicity on blood vessel on CNS Clinical features*Infective dose - 10-100 organisms *Gay bowel syndrome*S.flexneri(50-85%)>S.dysenteriae(8-25%)>S.sonnei(2-24%)>S.boydi(0-8%)*Reactive ahritis (S.flexneri), toxic neuritis*Intussusceptions, HUS*Toxic dilatation, Colonic perforation *Reiter's syndrome *Thrombotic thrombocytopenic purpura DiagnosisTreatment*Specimen - Mucus flakes of stool*Stool culture diagnostic on XLD agar*Sereny test*Mild to moderate dehydration - ORS*Severe cases - Ampicillin or Cotrimoxazole*DOC for MDR pathogen - Nalidixic acid Ref: Ananthanarayan 9th edition, 279 & 287


Question: Longest pathogenic Bacillus species is

Longest pathogenic Bacillus species is Bacillus anthracis (1.2 mm width and 3-5mm long). B. anthracis causes anthrax Largest known Bacillus species is B. megaterium, (1.5 mm width and 4 mm long).

General Microbiology Pa 1 (History, Microscopy, Stains and Structure and Physiology of Bacteria)


Question: Symptoms of C. botulinum food poisoning include double vision, inability to speak, and respiratory paralysis. These symptoms are consistent with

Clostridium botulinum growing in food produces a potent neurotoxin that causes diplopia, dysphagia, respiratory paralysis, and speech difficulties when ingested by humans. The toxin is thought to act by blocking the action of acetylcholine at neuromuscular junctions. Botulism is associated with high mortality; fortunately, C. botulinum infection in humans is rare.

Invasion of the gut epithelium by C. botulinum


Question: The single most common cause of Neonatal meningitis is

(A) Group B streptococcus # Group-B streptococcus has assumed great clinical importance as the single most common cause of neonatal meningitis in the West.> Infection in the new born is classified as the early onset type occurring within a week of birth & the late onset type developing between the 2nd and 12th weeks of life.> More common early onset type presents as septicemia meningitis or pneumonia, and is often fatal> Infection is acquired from the maternal vagina during birth> In the late onset type, infection is more often obtained from the environment.


Question: Arthus reaction is an example of

Examples of Type - 3 HSN

Arthus reaction
Serum sickness
Glomerulonephritis
Rheumatoid arthritis.


Question: In malaria definitive host is

Definitive host: Female Anopheles mosquitoes (not male anopheles) Intermediate host: Man. Infective form to man: Sporozoites presesnt in the salivary gland of mosquito Infective form to man when transmitted by blood transfusion or veical modetrophozoite Infective form to mosquito- Gametocyte Sand fly-cause leshmaniasis TSE TSE fly-cause sleeping sickness


Question: Gonococcus ferments

Gonococci resembles meningococci except that gonococci acidify only glucose, not maltose, but meningococci acidify both glucose and maltose. Reference: Textbook of Microbiology; Anathanarayan and panicker's; 10th edition; Page no: 234


Question: Drug of choice for UTI caused by pseudomonas is


Question: The single most important laboratory test for determining the virulence of staphylococci is


Question: Cysticercus cellulosae seen in

Cysticercus cellulosae is the larval form of taenia solium.(infective stage) Humans are infected by consuming inadequately cooked pork containing cysticercus cellulosae When taenia leads to cysticercosis the life cycle is.... Definitive host and intermediate host: man Infective stage : eggs of taenia solium Mode of infection: Man acquires infection by ingesting eggs Ref : panikers textbook of Medical parasitology 8th edition page 126


Question: Doc for Listeria Monocytogenes is

Doc - Ampicillin
Cotrimoxazole in case of penicillin allergy.


Question: Serotype of Adeno virus causing gastroenteritis is

Ans: a) 40.41 Ref: Text book of Microbiology Anantha narayanan 8th editionAdeno vimsNonenveloped ds DNA virusMostly in childrenPotential vactors in gene therapySpace vehicle shapedDiseasesRespiratory tract & eyes - most commonBladder & intestine - occasionallyDiseasesSerotypesPharyngitisTypes 1-7PneumoniaTypes 3 & 7Epidemic keratoconjunctivitis (shipyard eye)type 819 & 37 (rarely)a/c follicular conj (swimming pool)3, 4 & 11Diarrfiea40.41a/c hgic cystitis11 & 21Phayngo conjunctival fever3, 7 &14


Question: Berson and yellow 1st described the following test

Berson and Yalow discovered RIA in 1959 by which we can quantify antigens or hormones upto picograms-v sensitive than ELISA RIA /ELISA-indirect immunofluorescence tests Ref: Textbook of Microbiology Baveja 5th ed Pg 115


Question: Food poisoning is seen with

Enterotoxin is responsible for the manifestations of staphylococcal food poisoning - nausea, vomiting, and diarrhea 2-6 hour after consuming food contaminated by the preformed toxin. The toxin is a relatively heated stable, resisting 100deg C for 10 to 40 minutes depending on the concentration of toxin and nature of the medium. Ref: Ananthanarayan and Paniker&;s Textbook of Microbiology, 9th edition; pg no: 202


Question: Infective form in transfusion related malaria is

Infective form for transfusion related malaria is Trophozoites > merozoites.


Question: Ectothrix is due to

EctothrixEndothrix*Trichophyton mentagrophytes*Microsporum canis*Microsporum gypseum*Microsporum audouinii*Trichophyton verrucosum*Trichophyton rubrum*Trichophyton schenleinii*Trichophyton tonsurans*Trichophyton violaceum*Trichophyton soudanese(Jagdish Chander- Text book of Medical Mycology 3rd edition, p127)


Question: The animal used for monoclonal antibodies production is

Monoclonal antibodies are produced from mouse or from human using hybridoma technology eg: reslizumab is a humanized monoclonal antibody Ref: Textbook of Microbiology Baveja 5th ed Pg 138


Question: Primary site of infection in Cryptococcosis is

Infection is acquired by inhalation causing pulmonary cryptococcosis leading to mild pneumonitis. Ref: Textbook of Microbiology, Ananthanarayan and Paniker; 9th edition


Question: Prions are

Made up of bacterial and viral particles


Question: Cigar shaped yeast cells are seen with

- Cigar shaped yeast cells are seen in sporothrix schenkii on H and E staining of tissue sections at 37 degree C - it is yeast at 25 degree C - it is mould - Flower like sporulation appearance is seen in mould form of the sporothrix. H. capsulatum - histopath. show tiny oval yeast cell with narrow based budding C. neoformans - on microscopy gram staining, budding yeast is seen C. albicans - gram positive oval budding yeast cell with pseudohyphae


Question: Most common cause of common cold is

M/c cause of common cold is Rhino virus.


Question: The type of Diphtheria with highest moality is

Laryngeal diphtheria causes asphyxia due to mechanical obstruction of the respiratory passage by the pseudomembrane. Emergency tracheostomy may be necessary in such cases. Reference: Textbook of Microbiology; Anathanarayan and panicker's; 10th edition; Page no: 240


Question: Trusell and Johnson's medium is used for the cultivation of

Trussell and Johnson's medium is used for trichomonas which gives good growth containing peptone, sodium chloride, sod.thioglycate, normal human serum Ref: D.R. Arora.Medical parasitology 4th ed pg 46


Question: Woolsoer&;s disease is

Pulmonary anthrax : Common among workers of the wool factory due to inhalation of spores from infected wool. Hemorrhagic pneumonia with a high fatality rate. Hemorrhagic meningitis may occur as a complication. Reference: Textbook of Microbiology; Anathanarayan and paniker's; 10th edition; Page no: 250


Question: IgE is secreted by

All the antibodies are secreted by plasma cells.IgE is also secreted by plasma cells Mast cellsexpress a high-affinity receptor (FceRI) for the Fc region ofIgE. hence mostly mast cellsare found coated with IgE . It is mostly extravascular in distribution*Normal serum contains only traces (a few nanogramsper ml) but greatly elevated levels are seen in atopic(type 1 allergic) conditions such as, hay fever and eczema.

Immunology Pa 1 (Immune Response, Antigen-Antibody Reactions, Hypersensitivity, Structure of Immune System, Immunodeficiency Disorders)


Question: Streptococcus agalactiae


Question: Sound intensity required to elicit stapedial reflex is more than

The pure tone intensity range to elicit an acoustic reflex is 70 to 100db


Question: Most common site of Actinomyces is

Actinomycosis in human beings occurs in four main clinical forms: Cervicofacial: it is more common, with indurated lesions on the cheek and submaxillary regions Thoracic: Abdominal: Pelvic: Ref: Textbook of microbiology; Annthanarayan and paniker's; 10th edition; Pg: 399


Question: Growth factor needed for Salmonella


Question: Decreased O2 carrying capacity and Normal PO2 is a feature of

Subnormal level of haemoglobin causes decreased oxygen - carrying capacity of the blood. This, in turn, initiates compensatory physiologic adaptations such as :Increased release of oxygen from hemoglobin. o Increased blood flow to the tissues.Maintenance of the blood volume; andRedistribution of blood flow to maintain the cerebral blood supplyEventually, however, tissue hypoxia develops causing impaired functions of the affected tissues.


Question: Citron bodies are formed by

Clostridium septicum: form citron bodies, boat or leaf-shaped polymorphic bacilli. Motile by peritrichous flagella. Saccharolytic and produce abundant gas. Produce alpha, beta, delta and gamma toxin. Gas gangrene or malignant edema are characteristic Reference: Textbook of Microbiology; Anathanarayan and paniker's; 10th edition; Page no: 260


Question: Dental caries is caused by

Streptococcus mutans is an alpha Hemolytic streptococcus which is a pa of the normal flora of the oral cavity. This gram-positive coccus is commonly found in the mouth from where it can spread to cause dental caries or endocarditis in individuals with risk factors(dental extraction in individuals with damaged hea valves). The bacteria has a polysaccharide coat that allows it to stick to teeth and also to the damaged hea valves. It produces acid from sugar in saliva and this promotes erosion of tooth enamel. Reference: Textbook of Microbiology; Anathanarayan and panicker's; 10th edition; Page no: 221


Question: ova form in stool is not diagnostic in

strongyloides is oviviviparous hence eggs hatch immediately to produce rhabditi form larva which is the diagnostic form in stool ref : paniker 8th ed


Question: Neisseria gonorrhea causes

In men, Neisseria gonorrhea cause acute urethritis with a mucopurulent discharge containing gonococci in large numbers. Reference: Textbook of Microbiology; Anathanarayan and panicker&;s; 9th edition; Page no: 232


Question: The complement component with opsonin activity is

(B) C3b[?]Opsonins In Complement System:-C fragments released during the cascade reaction help in amplifying the inflammatory response.-C2 kinins are vasoactive amines and increase permeability.-C3a and C5a are anaphylatoxins (histamine releasing) and chemotactic.-C567 is chemotactic and also brings about reactive lysis.-C3b acts as opsonin.-C5-9 acts as cytotoxic.oThe process of coating a foreign particle targeting & preparing it for phagocytosis process is "Opsonization". Substances involved are opsonins. Main opsonins from complement system is C3oExamples of opsonins include:-Antibodies: IgG and IgA-Components of the complement system; C3b, C4b, and iC3b-Mannose Binding Lectin (MBL): Initiates the formation of C3b-Membrane Attack Complex (MAC): Includes C5b, C6, C7, C8 & polymeric C9oOpsonization & complement proteins:-Mainly C3b, iC3b & C4b-C3: Most abundant protein of all complementary proteins; Cleaves into C3a and C3b-C3a: Binds and activates mast cells & basophils, release histamine.-C3b: C3b is most critical component in both classical & alternative pathway. C3b attaches to bacterial surfaces for opsonization by phagocytes.[?]C3b way work:oC3b: Opsonization; Membrane Attack Complex (MAC)oOpsonization: C3b can do thioester bond. With this bond C3b bind with pathogen.oOn the other way Macrophage has two receptor CR1 and C5a receptor.oFor binding with pathogen it needs CP C5a. CP C5a bind with C5a receptor & allows CR1 to bind with C3b which attached with pathogen. This way Macrophage can perform phagocytosis by eating up the pathogen.[?]Biological Function of Complement:oBacteriolysis, cytosisoFunction of complement fragments-Opsonization: C3b, iC3b, C4b-Mediator of inflammation: C3a, C4a, C5a-Kinin: C2a, C5a-Chemotaxis: C3a, C5a, C567oC-dependent virolysisoClean up 1C: Interfere with formation of 1C, IC-C3b-CRI-RBC.oImmunological Regulation: C3, CR1, CR2, C3b-The first step in the alternative pathway is the binding of C3b to an activator.-C3b is continuously generated in small quantities in the circulation but in the free state it is rapidly inactivated by the serum protein factors H & I.-Bound C3b is protected is such inactivation and interacts with a serum protein called factor B (C3 proactivator) to form a magnesium dependent complex 'C3b, B'


Question: Optic tract fibers project to the superior colliculi for

Optic tract fibers project to the superior colliculi for reflex gazesPretectal area for the light reflexSuprachiasmatic nucleus of the anterior hypothalamus for generation of circadian rhythms


Question: Risk of pneumococcal meningitis is seen in

Streptococcus pneumoniae causes infection only when host resistance is lowered by contributory factors such as respiratory viral infection, pulmonary congestion, stress, malnutrition, immunodeficiency and alcoholism. Splenectomy and sickle cell disease are impoant predisposing conditions. Meningitis is the most serious of pneumococcal infection. pneumococcal meningitis occurs at all ages. Untreated cases are almost invariably fatal. Even with antibiotic therapy, the case fatality rate is about 25%. Reference: Textbook of Microbiology; Anathanarayan and panicker's; 10th edition; Page no: 226

Patient undergone neurosurgical intervention


Question: Dermatophyte affecting the hair, nail, and skin is

The three genera of medically impoant dermatophytes (literally, skin-plants) are Epidermophyton, Microsporum, and Trichophyton.--Trichophyton: infects skin, hair, and nails-- Microsporum: infects hair and skin-- Epidermophyton: infects nails and skinRef: Sherris Medical Microbiology; 6th edition; Chapter 5; Medically Relevant Fungi; Page no: 335


Question:
Organism most frequently associated with urinary
tract infections is


Question: Wheel shaped virus is

Wheel shaped - Rota virus
Rod shaped - TMV
Bullet shaped - Rabies
Brick shaped - POX


Question: Amount of ORS given in 4 KG children with diarrhoea

The family should be provided with at least two days woh of ORS packets.WHO recommends, in addition to infants continued to be breastfed, that children older than six months be given some food before being sent home, which helps to emphasize to parents the impoance of continuing to feed the child during diarrhoea.Body wt = 4 kg.Requirements 75 ml/kg.So total requirements 75x4 = 200 ml.


Question: Discharging sinus is seen in

Mycetoma begins as a subcutaneous swelling usually of the foot which enlarges and borrows into the deeper tissues producing abscess. It burst with the formation of chronic multiple sinuses discharging viscous seropurulent fluid containing granules. Ref: Textbook of Microbiology, Ananthanarayan and Paniker; 9th edition


Question: Lymphangitis is caused by

S. pyogenes causes a variety of suppurative infections of the skin, including infections of wounds and burns, with a predilection to produce lymphangitis and cellulitis. Ref: Textbook of microbiology; Ananthanarayan and paniker's; 10th Edition; Pg:215


Question: Operation theatre sterilisation is done by

UV rays are used to disinfect OT for 30-45 min exposure Formaldehyde gas also can be used for fumigation of operation theatres. Ref : Ananthanarayana textbook of Microbiology 9th edition Pgno : 33


Question: Superantigen is produced by

Superantigens are that antigen which can generate the high immune response upon introduction


Question: Shift of oxygen binding curve to the left occurs because of

Causes of the shift to the left include:Decreased H+(increased pH).Decreased 2,3-DPG.Stored blood.Polycythemia Decreased temperatureDecreased P CO2Causes of the shift to the right include:Increased H+( decreased pH)Increased 2,3-DPGIncreased temperatureIncreased PCO2


Question: Indicator used in Macconkey medium

Macconkey's medium contains peptone, Lactose, agar, neutral red and taurocholate.


Question: In case of appendicitis, if the pain is exacerbated on medial rotation of the thigh, the position of appendix is in

Dunphy's sign: Any movement, including coughing, may cause pain.Rovsing's sign: Pain in the right lower quadrant during palpation of the left lower quadrant.Iliopsoas sign: "Obraztsova's sign' pain on extension of the hip which relieves on flexing the hip into the "fetal position" (due to inflammation of the peritoneum overlying the iliopsoas muscles and inflammation of the psoas muscles themselves). Theis is typical of a retrocecal appendix.Obturator sign: Pain in flexion and internal rotation of the hip (due to irritation of obturator internus). This is typical of a pelvic appendix.Blumberg sign: Deep palpation of the viscera over the suspected inflamed appendix followed by the sudden release of the pressure causes the severe pain on the site indicating positive Blumberg's sign and peritonitis.Volkovich -Kocher (Kosher)'s sign: The appearance of pain in the epigastric region or around the stomach at the beginning of disease with a subsequent shift to the right iliac region.Sitkovsky (Rosenstein)'s sign: Increased pain in the right iliac region as the patient lies on the left side.Baomier - Michelson's sign: Increased pain on palpation at the right iliac region as the patient lies on left side compared to when the patient was in the supine position.Aure - Rozanova's sign: Increase pain on palpation with a finger in right Petit triangle. Typical in the retrocecal position of the appendix. Boundaries of Petit triangle are the iliac crest, External oblique muscle, and Latissimus Dorsi muscle.


Question: Vibrio parahemolyticus is associated with


Question: The leather term is used for

Diphtheria was first recognized as a clinical entity by Bretonneau who called it "diphtheria" (from diph-theros, meaning leather). The name is derived from the tough, leathery pseudomembrane formed in the disease. Reference: Textbook of Microbiology; Anathanarayan and panicker's; 10th edition; Page no: 239


Question: The incubation period for Bacillus Cereus in case of the emetic type of food poisoning

Bacillus cereus: an impoant cause of food poisoning. Two patterns: diarrheal and emetic. Emetic type: associated with consumption of cooked rice, usually fried rice from restaurants. Nausea and vomiting 1-5 hours after the meal. Bacilli present in large numbers in cooked rice and fecal samples from these patients. Diarrheal type: associated with a wide range of foods including cooked meat and vegetables. It is characterized by diarrhea and abdominal pain, 8-16 hrs after ingestion of contaminated food. Reference: Textbook of Microbiology; Anathanarayan and paniker's; 10th edition; Page no: 253


Question: In an asthmatic patient; the causative agent was found to be fungi with septate hyphae. The organism is

A fungus with septate hyphae in the asthmatic patient can be none other than Aspergillus, and this is a case of allergic bronchopulmonary aspergillosis. Ref: Ananthanarayana textbook of Microbiology 9th edition Pgno : 609


Question: Staphylococcus is

Gram positive bacteria

There are 6 classic gram-positive bacteria that cause human disease.

Of these 2 are cocci

Staphylococci
Streptococci (including anaerobic peptostreptococci)

Other 4 are bacilli

Corynebacterium
Bacillus
Clostridium
Listeria


Question: Infection of following organism has clinical features resembling erythroblastosis foetalis

* Clinical features of congenital CMV infection is similar to those of Erythroblastosis fetalis Symptoms are: - * IUGR * Hepatosplenomegaly * Jaundice * Thrombocytopenia * Microcephaly Ref:- Greenwood medical microbiology 18th ed; pg num:- 439


Question: Contact isolation is done for

* Strict isolation is must for patient diagnosed with diphtheria. * Even when clinically suspected, patient must be isolated. * A staff who has known immunisation history should nurse the patient. Ref:- Greenwood medical microbiology 18th ed; pg num:- 202


Question: Corynebacterium diphtheria produce black or grey colonies on the following agar

Corynebacterium produce black or grey colonies on potassium tellurite blood agar It acts as a selective medium for its growth Ref: Textbook of Microbiology Baveja 5th ed Pg 211


Question: The major cause of us is

Favus is a chronic infection caused most commonly by T schoenleinii and usually affecting the scalp. Most common organism associated with us is Trichophyton schoenlenii. E. floccosum- cause Tinea unguium (nail beds) M. canis- cause ECTOTHRIX(infection of hair) T. rubrum- cause Tinea cruris (groin area)


Question: Disinfection of the rooms can be done by using


Question: Buerger's disease is not associated with

Buerger's disease (thromboangitis obliterans)Occlusive disease of small and medium-sized aeriesThrombophlebitis of superficial or deep veinsRaynaud syndromeAffects males (<30yrs)Angiography sometimes showed a characteristic 'corrugation' of the femoral aeries as well as the distal aerial occlusions and helps to distinguish the condition from aggressive atheroma of early onset.

Thrombophlebitis of deep or superficial veins

Involvement of large sized aeries primarily

Characteristic 'corrugation' of femoral aeries on angiography


Question: Investigation of choice of diphtheria carrier is

One or two swabs from the lesions are collected under vision, using a tongue depressor. Smears stained with methylene blue or one of the special stains (Neisser's or Albes) will show the bacilli with metachromatic granules and in the typical arrangement. Reference: Textbook of Microbiology; Anathanarayan and panicker's; 10th edition; Page no: 242


Question: Culture media used for Leishmania is


Question: Drug of choice for paracoccidioidomycosis is

Amphotericin B is the drug of choice for most of the systemic fungal infections It acts by forming pores in the cell membrane leading to escape of various major electrolytes from fungus Ref: Baveja 5th ed pg: 554


Question: Disposable syringes are sterilized by

Disposable plastics eg : Rubber or plastic syringes infusion sets, catheters are sterilized by Ionizing radiation.


Question: The most common pathogens responsible for nosocomial pneumonia in ICU are

Nosocomial pneumonia is caused by mainly Multi-drug resistant Gram negative bacilli (MDR-GNB)


Question: Normal nasofrontal angle is

Nasofrontal angle is 115-130 degreesNasolabial angle is 95-105 degrees for females, 90-95 degrees for males


Question: Diene method is used for

Mycoplasma colonies may be seen with a hand lens but are best studied after staining by the Dienes method. For this, a block of agar containing the colony is cut and placed on a slide. It is covered with a coverslip on which an alcoholic solution of methylene blue and azure has been dried. Ref: Textbook of microbiology; Ananthanarayan paniker's; 10th edition; Pg:394


Question: Selective medium for Bacillus anthracis

PLET is selective medium for Bacillus anthracis.


Question: Culture medium used for streptococcus pneumoniae


Question: Obligate intracellular parasite among the following is

Obligate intracellular parasites cannot reproduce outside their host cell, meaning that the parasite's reproduction is entirely reliant on intracellular resources. Toxoplasma,Cryptosporidium Bacteria-chlamydia ,Rickettsia


Question: Next to HBV, virus implicated in hepatocellular Ca is

Ans. is 'a' i.e. HCV Hepatitis B and Hepatitis C viruses can cause hepatocellular carcinoma.


Question: Adenovirus 40/41

The diagnosis of a viral infection is made easier by the creation of a greater number of diagnostic virology laboratories during the past few decades. In order for viral diagnosis to be successful, the most appropriate specimen must be collected for the disease in question.Many viruses can be isolated from feces. Of the viral groups in these questions, adenovirus 40/41 is the most common stool isolate. Norwalk agent and other caliciviruses may also be isolated or detected from stools, but usually only in specialized laboratories.


Question: The muzzle velocity of given firearm is

The revolver, which tends to have a low muzzle velocity of 150 m/s, is a sho barreled weapon with its ammunition held in a metal drum, which rotates each time the trigger is released.The muzzle velocity of pistols varies between 300 and 360 m/s.The rifle is a long-barreled shoulder weapon capable of firing bullets with velocities up to 1500 m/s.


Question: Cell fusion of HIV with target cell is done by

Ans. is 'b' i.e., gp 41 gp 120 - Binding of HIV to CD4 antigen on T-cell.gp 41 - Fusion of HIV to torget cell (T-cell)The HIV envelop contains two glycoproteins, surface gp120 that is noncovalently altached to transmembrane protein, gp41.The initial step in infection is the binding of gp120 envelop glycoprotein to CD4 molecules.This binding leads to a conformational change that result in the formation of a new recognition site on gp120 for the coreceptor CCR5 or CXCR4.The next step involves conformational changes in gp41.These changes results in the inseion of fusion peptide at the tip of gp41 into the cell membrane of target cell (CD4 T-cells or macrophages).After fusion, the virus core containing the HIV genome enters the cytoplasm of the cell.


Question: A child had pustular lesion on leg. On grainstaining gram positive cocci are seen. To establish the diagnosis of Group A streptococcal erythroderma, the test used is

Bacitracin sensitivity (Ref: Harrison 16thle p 741, Anantnatyan] Streptococcal erythroderma is caused by streptococcus pyogenus Streptococcus pyogenus is b hemolytic streptococci and is Bacitracin positive.


Question: Subterminal spores are found in

The shape and position of spores vary in different species and these are of use in identifying and classifying clostridia.subterminal spores are seen in clostridium perfringens,the bacillus appearing club shaped Ref:anantnarayan and paniker's microbiology 10th edition


Question: Dwarf tapeworm refers to

EponymParasiteThermophilic amoeba/ Brain eating parasiteNaegleria fowleri Fish tape worm / Broad tape worm Diphyllobothrium latum Beef tape worm Taenia saginata Pork tape worm Taenia solium Dog tape worm Echinococcus granulosus Dwarf tape worm Hymenolepis nanaRat tape wormHymenolepis diminutaOriental blood fluke Schistosoma japonicum Chinese liver fluke / Oriental liver fluke Clonorchis sinensis Sheep liver flukeFasciola hepatica Lancet fluke Dirocoelium dendriticum Giant intestinal fluke Fasciolopsis buski Oriental lung fluke Paragonimus westermani Trichina worm Trichinella spiralis Whip worm Trichuris trichiura Hook worm Ancylostoma duodenale , Necator americanus Round worm Ascaris lumbricoides Seat worm / Pin worm / Thread worm Enterobius vermicularis African eye worm Loa loa Convoluted filaria / Blinding filarialOnchocerca volvulus Dog hea worm Dirofilaria immitis Guinea worm Dracunculus medinensis Rat lung worm Angiostrongylus cantonensisAns: C (Ref: K.D Chatterjee 13th edition, p166)


Question: Acellular peusis vaccine contains

Flagillary hemagglutinin, peussis toxin, fimbrial Whole cell peussis vaccines consist of inactivated Bordetella peussis bacterial cells. - They arc given as combinations with diphtheria and tetanus toxoids (DTP) vaccines. - Whole cell DTP vaccines cause several local adverse effects. (e.g., erythema, swelling pain at the injection site) and other mild systemic events e.g., (drowsiness, .fretfulness and anorexia). - They are also associated with serious systemic adverse effect such as convulsions with or without fever and hypotonic hyporesponsive episodes sometimes they may also be associated with encephalopathy. Concerns about the safety prompted the development of more purified (Acellular) peussis vaccine that are associated with a lower frequency of adverse effects and are as effective in preventing peussis as the whole cell vaccine. There is yet no consensus about the antigenic composition of an ideal acellular peussis vaccine. A cellular peussis vaccines currently available .from different manufactures should be considered as different and unique products because of the presence of one or more different components which are : ? - Chemically or genetically detoxified peussis toxindeg (PT toxoid). - Filamentous hemagglutinin - 69k Da outer membrane protein (also known as peactin)deg - Fimbrial-2 and fimbrial-3 antigens. - These components are contained in different concentrations and with different degrees of adsorption. - It was believed that active peussis toxin and endotoxin are responsive for the high incidence of adverse effects of whole cell vaccine. - There fore the acellular peussis vaccine contains detoxified peussis toxin or the toxoided peussis toxin and it does not contain the endotoxins present in whole cell peussis vaccine. They are associated with considerably lesser side effects than whole cell vaccine and have similar efficacy to a cellular peussis vaccine (90%).

Peactin, flagillary hemagglutinin, cytotoxin, endotoxin

Peactin, flagillary hemagglutinin, fimbriae, endotoxin

Flagillary hemagglutinin, peusis toxin, fimbriae


Question: Endemic fungal infection is

Coccidioidomycosis is endemic in dry, arid regions of south-west and USA where the fungus is present in soil and in rodents. Ref: Textbook of Microbiology, Ananthanarayan and Paniker; 9th edition


Question: Leptospira in diagnostic labs is grown in

Leptospira can be grown in media enriched with rabbit serum. several liquid and semi-solid media, such as Kohof's, Stua's and Fletcher's media, have been described. Semisynthetic media such as EMJH are now commonly used. They are aerobic and microaerophilic. Ref: Textbook of microbiology; Ananthanarayan and paniker's; 10th edition; Pg: 388


Question: Urethritis in males is not caused by

H Ducreyi course soft sore chancroid Infections cuase urethritis Neisseria gonorrhea chlamydia trachsmati&;s Trichsmonas Vaginalis Mycoplasma genitalium ref : ananthanaryana


Question: Aflatoxins are produced by

The best-known mycotoxin is aflatoxin produced by Aspergillus flavus. It is present in ground nuts, corns and peas. It can cause hepatoma in animals. Ref: Textbook of Microbiology, Ananthanarayan and Paniker; 9th edition


Question: First antibody to appear in intrauterine life


Question: Resolution power of light microscope is

Ans :c) 200 nmThe resolving power of light microscope is limited by the wave length of light. With visible light, using the best optical system, the limit of resolution is 200- 300 nm.Extra points:* Wavelength of electron in Electron microscope- 0.0005nm* Resolving power of electron microscope -1 nm* Reflected light rather than transmitted light is med in Dark field /dark ground microscope


Question: Rose waaler test is

Ref: Ananthanarayana textbook of Microbiology 9th edition Pgno : 110,181 Agglutination - Insoluble antigen + antibody at a suitable temperature and pH - Clumps formation Slide agglutination Identification of bacterial isolates from clinical specimens Blood grouping, Cross-matching Tube agglutination WIDAL Typhoid Standard agglutination test Brucellosis Microscopic agglutination test Leptospirosis Heterophile agglutination test Weil Felix test Rickettsial infection Streptococcal MG agglutination test Primary atypical pneumonia Paul Bunnell test Infectious mononucleosis Antiglobulin test Direct Coombs test Detect fetal Rh Ab Indirect Coombs test Detect maternal Rh Ab Passive agglutination test Hemagglutination Rose Waaler test Latex agglutination test Detection of ASO, CRP, RA factor, HCG Co-agglutination test Diagnosis of Legionellosis, Gonorrhea

Passive agglutination for Rheumatoid ahiritis

Active agglutination for Rheumatoid ahiritis

Passive agglutination for Rheumatic fever

Active agglutination for Rheumatic fever


Question: Citron bodies" boat or leaf shaped pleomorphic organism in an exudate is

Citron bodies and boat or leaf shaped pleomorphic bacilli with irregular staining suggest CL septicum". Clostridium Clostridial species are : Gram positive Anaerobic (obligate anaerobe) Spore forming Bacilli Motile by peritrichate flagella except C perfringens and C. tetani type IV which are non motile. Non capsulated except C. perfringens and C. butyricum which are capsulated Pathogenesis is due to exotoxin not endotoxin. Clostridium botulinum causes botulism not gas gangrene. REF : ananthanarayana 10th ed


Question: Investigation of choice for detection of syphillis in a patient after 2 course of complete therapy

Ans. is `b' i.e., VDRL To monitor the response to therapy non treponemal serological tests (RPR or VDRL) are used. Features of serological tests . Most senstive serological test in primary syphilis . First test to become positive . The test of choice for rapid serological diagnosis in a clinic or office setting . Tests for monitoring the responce of therapy . Testing of large number of sera for screening or diagnostic purpose . Tests for confirmation of the diagnosis . Measurment of Ig M in a neonate for congenital syphilis . The diagnostic test . Reagin antibodies tests (RPR and VDRL) becomes positive after 3-5 weeks of Infection (7-10 days after the appearance of primary chancre). In Lyme disease VDRL test is negative, but FTA-ABS may be positive. All serological tests may be positive (false positive) in non veneral treponematoses. eg in yaws, Pinta and endemic syphilis. . Presence of Ig M in a neonate confirms syphilis, as IgM can not cross placenta. But Ig G can be passively transfered from the infected mother to newborn. . Reagin antibody in syphilis is Ig G while reagin antibody in atopy (hypersensitivity reaction) is Ig E.


Question: Traveller's diarrhoea is most commonly caused by

Ans. a (ETEC). (Ref. Harrison, 18th/Table 149-2; Chapter 149. Diseases by Gram-Negative Enteric Bacilli)Five types of E.coli include:1. ETEC (enterotoxogenic E.coli)2. EIEC (enteroinvasive E.coli)3. EPEC (enteropathogenic E.coli)4. EHEC (enterohemorrhagic E.coli)5. EAEC (enteroaggregative E.coli)Traveller's diarrhoea is most commonly caused by enterotoxogenic E.coli and then the other common organism responsible is S. dysenteriae.Intestinal Pathogenic E. ColiPathotypeEpidemiologyClinical SyndromeDefining Molecular TraitResponsible Genetic ElementSTEC/EHECFood, water, person-to- person; all ages, industrialized countriesHemorrhagic colitis, HUSShiga toxinLambda-like Stxl- or Stx2- encoding bacteriophageETECFood, water; young children and in travellers to developing countriesTraveller's diarrheaHeat-stable and - labile enterotoxins, colonization factorsVirulence plasmid(s)EPECPerson-to-person; young children and neonates in developing countriesWatery diarrhea, persistent diarrheaLocalized adherence, attaching and effacing lesion on intestinal epitheliumEPEC adherence factor plasmid pathogenicity island (locus for enterocyte effacement)EIECFood, water; children and in travellers to developing countries.DysenteryColonic epithelial cell invasion intra- cellular multipli cation, cell-to-cell spread.Multiple genes contained primarily in a large virulence plasmidEAEC?Food, water; children and in travellers to developing countries; all ages, industrialized countriesTraveller's, acute, Persistent diarrheaAggregative/diffuse adherence, virulence factors regulated by AggRChromosomal or plasmid associated adherence and toxin genesE.coli toxin (GSa), cholera toxin (Gsa), & Pertusis toxin (Gla) cause ADP-ribosylation


Question: Recommended temperature of Autoclave is

Recommended temperature is

121°C for 5 mins
126°C for 10 mins
134°C for 3 mins


Question: pH of Sabouraud dextrose agar is

Sabourauds dextrose agar (Selective media) is maintained at pH of 5.4 and same is used for isolation of fungus. The low pH of the medium and addition of chloramphenicol and cycloheximide to the medium inhibit the growth of bacteria in the specimen and thereby facilitate the appearance of slow-growing fungi Image: SDA slant with fungal growth

General Microbiology Pa 1 (History, Microscopy, Stains and Structure and Physiology of Bacteria)


Question: R. seeberi grows in

Numerous attempts have been made for many decades to propagate R.seeberi, from either rhinosporidial tissue or from saprophytic sources, on inanimate as well as cell-containing media in vitro. Various types of culture media with nutritional additives have been used. There has been no repo of successful in vitro culture and propagation in subculture. ** R.seeberi is no more considered a fungi "R.seeberi, paicularly that it is not a classic fungus "but rather the first known human pathogen from the DRIPs clade, a novel clade of aquatic protistan parasites. (Mesomycetozoa) " Ref : Ananthanarayana textbook of Microbiology 9th edition Pgno : 603


Question: One of the following is a treponemal test for diagnosis of syphilis


Question: Albe&;s stain is used for

Albe 's or Neisser's stain: smears of Corynebacterium diphtheriae when stained with Albe's stain will show the bacilli with metachromatic granules. Delicate green bacilli with purple-blue metachromatic granules can be seen. Bacilli take up stain due to metachromatic granules which are composed of polymetaphosphate and serve as storage granules. Reference: Textbook of Microbiology; Anathanarayan and paniker's; 10th edition; page no 242


Question: Most common organism responsible for gas gangrene


Question: Louis pasteur is not associated with

Ans. is 'c' i.e., Discovery of M. Tuberculosis . Louis pasteur is associated with . Development of live vaccine (first was anthrax) . Development of vaccine for rabies (hydrophobia) . Introduction of technique of sterilization . Disprove the theory of spontaneous generation (abiogenesis) . Established the different growth need of different bacteria (helped in complex media) . Coined the term vaccine M. tuberculosis was discovered by Robe Koch


Question: The patient receives a score of 8 on her biophysical profile. The results are

A BPP score of 8 or 10 is normal.A score of 0 to 2 dictates imminent delivery because fetal asphyxia is probable.Scores of 4 to 6 require repeat testing and delivery if persistent.

The results are equivocal, and she should have a repeat BPP within 24 h

The results are abnormal, and she should be induced

The results are abnormal, and she should undergo emergent cesarean section


Question: Staphylococcus in the stool occurs in

Enterotoxin is responsible for the manifestation of staphylococcal food poisoning-nausea, vomiting, and diarrhea 2-6 hrs after consuming food contaminated by a preformed toxin. In food poisoning, feces and the remains of suspected food should be collected. Ref: Textbook of Microbiology; Ananthanarayanan and Panicker; 10th edition; Page No: 204, 206


Question: Buruli ulcer is caused by

- Buruli ulcer is caused by atypical mycobacteria named as Mycobacteria ulcerans - Mycobacteria ulcerans- It is a water borne skin pathogen which is categorised under non - photochromogens ( Runyon's classification ) This cause lesions which are typically painless ulcers and nodules. It has narrow temp.range of 31 degree - 34 degree C

Systemic Bacteriology (Gram Positive Bacilli, Gram Negative Bacilli)


Question: Inveed fir tree appearance is characteristic of

Anthrax bacilli is gram-positive and is found singly, in pairs or in sho chains. On gelatin stab culture, a characteristic inveed fir tree appearance is seen in the case of anthrax bacilli, with slow liquefaction commencing from the top. On blood agar, the colonies are non-hemolytic, though occasional strains produce a narrow range of hemolysis. In broth, growth occurs as floccular deposits, with little or no turbidity. Reference: Textbook of Microbiology; Anathanarayan and panicker's; 10th edition; Page no: 251


Question: Meningitis in immunocompromised host is frequently caused by

(B) Cryptococcus neoformans # Cryptococcus neoformans is the leading cause of meningitis in immunocompromised patients (AIDS).


Question: Darling disease is caused by

Histoplasmosis is described by Darling in 1905, so-called Darlings disease. Ref: Textbook of Microbiology, Ananthanarayan and Paniker; 9th edition


Question: The first cell culture vaccine was

An inactivated rabies vaccine for human use was first prepared in cell culture. It was shown that the human diploid cell (HDC) strain WI-38 was a suitable substrate for the propagation of the Pitman-Moore (PM) strain of fixed rabies virus. Ref : Ananthanarayana textbook of Microbiology 9th edition Pgno : 534

Purified chick embryo cell ( PCEC ) vaccine


Question: Most common cause of "Polymyositis" is


Question: Lyme's disease is caused by

Lyme disease is named after the town of Lyme, Connecticut, where clusters of cases in children were identified. Lyme disease is caused by the spirochete Borrelia burgdorferi and is transmitted to humans by the bite of a small Ixodes tick. The disease has early manifestations with a characteristic skin lesion, erythema migrans, along with flu-like symptoms, and late manifestations often with arthralgia and arthritis.


Question: Botulism causes

Clostridium botulinum produces Type A toxin. It acts by blocking the production or release of acetylcholine at the synapses and neuromuscular junction. Thus block neuromuscular transmission. Onset is marked by diplopia, dysphagia, and dysahria due to cranial nerve involvement. Symmetric descending flaccid paralysis is a characteristic pattern, ending in death by respiratory paralysis. Reference: Textbook of Microbiology; Anathanarayan and paniker's; 10th edition; Page no: 269


Question: Fungi of medical importance belongs to

Deuteromycota (Fungi imperfectii) - Sexual state is absent - most medically important fungi.


Question: Dose of Rabies immunoglobulin is

The anti-rabies serum is given in class III bites (Single or multiple transdermal bites or scratches, licks on broken skin, Contamination of mucous membranes with sal, exposure to bats)It is found to prolong the incubation period.Passive immunization in rabies may be given by :Horse Anti-rabies serum: 40 IU/kg body wt (up to max 3000 units), infiltrated in the wound, & the rest gave IMHuman Rabies Immunoglobulin: (preferred) 20 IU/kg body wt infiltrated in the wound, & the rest given i.m.


Question: Botulism is a disease of

Clostridium botulinum produces a powerful exotoxin. It acts by blocking the production or release of acetylcholine at the synapses and neuromuscular junction. Thus blocks neuromuscular transmission. Reference: Textbook of Microbiology; Anathanarayan and paniker's; 10th edition; Page no: 269

Neural transmission caused by the toxin of the bacterium clostridium botulinum

Muscular transmission caused by the toxin of the bacterium clostridium botulinum

Neuromuscular transmission caused by the toxin of the bacterium clostridium botulinum

Non neuromuscular transmission caused by the toxin of the bacterium clostridium botulinum


Question: Loeffler's serum slope doesn't contain

LSS is used for the culture of C Diptheria It doesn't contain sheep blood .sheep blood is present in blood agar LSS is a type of enriched media Ref: CP Baveja 4th ed Pg:46


Question: Best method of preventing transmission of MRSA infection is

Measures for the control of staphylococcal infections in hospitals:*Isolation of patients with open staphylococcal lesion*Detection of staphylococcal lesions among doctors and health care workers*Hand washing is the oldest, simplest and most effective method of preventing MRSA and other cross infections.*Following strict aseptic precautions (Ref: Ananthanarayan 9th edition, p204)


Question: Wood&;s light can be used for evaluation of

Wood&;s light can be a diagnostic aid in determining fungal infection (Microsporum mainly) of skin or scalp. Tinea capitis is caused by Microsporum species. Reference: Textbook of Microbiology; Baveja; 4th edition


Question: Jumping gene is


Question: The causative organism in Madura Mycosis Mycetoma is

Eumycetoma - Acremonium falciforme, Madurella mycetomi, Madurella grisea, Pseudoallescheria boydii, Exophiala jeanselmei. Actimomycetoma- Actinomadura Madurai, Actinomadura Pelletier, Nocardia brasiliensis, Streptomyces somaliensis. Ref: Textbook of Microbiology, Ananthanarayan and Paniker; 9th edition


Question: Nagler's  reaction is an type of

Cl. perfringens is grown on a medium containing 6% agar, 5% Fildes' peptic digest of sheep blood and 20% human serum or 5% egg yolk in a plate.
Neomycin sulphate may be added to the medium to make it more selective by inhibiting aerobic spore bearers and coliforms.
To one half of the plate, antitoxin is spread on the surface.
The inoculated culture plate is incubated at 37°C for 24 hours.
Colonies on the half plate without the antitoxin will be surrounded by opacity while colonies on the other half with antitoxin shows no opacity, due to specific neutralization of the alpha toxin.
Alpha toxin (lecithinase C) splits lecithin into phosphoryl choline and a diglyceride (lipid).
The lipid deposits around the colonies resulting in opacity.

Ref : textbook of microbiology, C P Baveja 5th edition pg no:228