Question: A 15-year-old girl presents to the clinic due to concern that she may be pregnant. She had unprotected sexual intercourse earlier that morning and requests emergency contraception. She has had regular menses since menarche, and her last menstrual period ended 8 days ago. She has no significant medical history. Her temperature is 98.6°F (37°C), blood pressure is 114/71 mmHg, pulse is 81/min, and respirations are 12/min. A physical exam is unremarkable. A urine pregnancy test is negative. The patient asks for an emergency contraceptive pill and would prefer that her parents not be notified about her visit. In most states, which of the following is the most appropriate next step in the management for this patient?

Do not prescribe emergency contraception given that the patient is under 18 years old

Obtain parental consent before providing emergency contraception

Answer: Prescribe levonorgestrel pill

Explanation:
This patient with recent unprotected intercourse and a negative pregnancy test is a candidate for postcoital emergency contraception. She should receive the levonorgestrel or ulipristal pill, which in most states does not require parental consent.

Patients with a positive pregnancy test are not candidates for emergency contraception because implantation has already occurred, but patients with recent unprotected intercourse but a negative pregnancy test should receive the levonorgestrel pill (plan B) or ulipristal pill. These pills should be administered as soon as possible after intercourse. This is because the efficacy of the pills decrease after 72-120 hours post-intercourse. The high doses of progestin in these pills delay ovulation by blocking the LH surge, thereby preventing pregnancy. In most states, adolescents can receive emergency contraception without parental consent or notification.

Batur et al. present the current options available for emergency contraception. They discuss how ulipristal acetate tends to be more efficacious compared to levonorgestrel when used more than 72 hours post-coitally. They recommend that all providers who treat young women be familiar with the options and indications for emergency contraception.

Incorrect Answers:
Answer A: It is inappropriate to not administer emergency contraception despite the patient being under 18 years old. Adolescent patients at risk of pregnancy after unprotected intercourse who request emergency contraception should be presented with viable options.

Answer B: Obtaining parental consent before providing emergency contraception is an incorrect choice in most states. Most states allow adolescents to receive confidential care for contraception and pregnancy without parental involvement, consent, or notification.

Answer C: Prescribing high-dose oral contraceptives can be done in special circumstances to delay ovulation by patients taking multiple pills at once. However, combination oral contraceptives are less commonly used for post-coital contraception as they have significant side effects at high doses and are less effective than levonorgestrel pills.

Answer E: In patients with a positive pregnancy test (after implantation has occurred), misoprostol can be used for pregnancy termination by stimulating myometrial contractions. It does not prevent pregnancy. The use of drugs to terminate pregnancy varies significantly from state to state.

Bullet Summary:
Adolescents seeking emergency contraception may do so without parental consent or involvement in most states.


Question: A 65-year-old woman presents to her family doctor to reestablish care since losing her insurance. She has not had time for regular check-ups. She exercises 3-4 times a week and consumes red meat sparingly. She drank and smoked cigarettes socially with coworkers but never at home or on vacation. She wakes up with achy wrists and elbows that she suspects is from years of using a computer keyboard. She completed menopause at age 52. Her family history is notable for coronary artery disease on her father's side and colon cancer on her mother's side. She last had a colonoscopy 5 years ago that revealed no abnormal findings. Her temperature is 99°F (37.2°C), blood pressure is 125/83 mmHg, pulse is 82/min, respirations are 12/min, and oxygen saturation is 99% on room air. Her physical exam is grossly unremarkable. What diagnostic test should this patient receive?

Answer: Mammography

Explanation:
This vignette describes an otherwise healthy elderly woman seeking to establish primary care. Among the answer choices, mammography is the most appropriate diagnostic test to recommend.

Mammography is a screening tool for breast cancer that becomes most effective in postmenopausal patients because of less glandular breast tissue compared to younger patients. According to the United States Preventive Services Task Force, all women aged 50-74 should have mammograms every 1-2 years. It is controversial whether screening mammography should begin as early as age 40. Women with 1st-degree relatives with breast cancer should begin screening 10 years before the age of the family member's diagnosis.

Seely and Alhassan review the evidence regarding the screening methods used for breast cancer. They discuss how screening every 1-2 years decreases breast cancer mortality. They recommend using judicious mixed modal methods of screening.

Incorrect Answers:
Answer A: Routine chest radiography for lung cancer screening in low-risk patients is not recommended by the USPSTF. Chest imaging can be used to screen for lung cancer in patients with a significant smoking history.

Answer B: Colonoscopy for colon cancer screening is recommended every 10 years starting at age 50. This patient already had a colonoscopy 5 years ago so she does not need another exam at this time.

Answer D: Pelvic ultrasound for ovarian cancer screening is not currently recommended by the USPSTF. Ovarian cancer detection should also be performed in patients who are symptomatic.

Answer E: Vitamin D level for osteoporosis screening is not recommended. DEXA scans would be more appropriate for testing bone density.

Bullet Summary
According to the United States Preventive Services Task Force, all women aged 50-74 should have mammograms every 1-2 years.


Question: A 27-year-old man presents to the emergency department with altered mental status. He was running a marathon but became confused halfway through the race. He arrives unable to coherently answer questions and is not sure where he is. He has a history of a seizure disorder. His temperature is 105°F (40.6°C), blood pressure is 116/68 mmHg, pulse is 167/min, respirations are 29/min, and oxygen saturation is 99% on room air. Physical exam reveals a confused man who is moving all 4 extremities and is protecting his airway. During the exam, he develops a tonic-clonic seizure, which lasts 1 minute and then terminates on its own. The patient is given intravenous fluids, and basic laboratory studies are drawn and pending. A urine dipstick is positive for red blood cells. Which of the following is most likely to be seen on laboratory testing?

Answer: Hypocalcemia

Explanation:
This patient is presenting after running a marathon with hyperthermia and altered mental status suggestive of heatstroke. In the setting of his recent exertion, tonic-clonic seizure, and urine dipstick positive for red blood cells, he is likely suffering from rhabdomyolysis, which most commonly causes hypocalcemia.

Rhabdomyolysis occurs when there is a breakdown of the muscle cells. It can occur with exertion (such as marathon running or weight lifting), seizures (from prolonged and intense contraction of the muscles), cocaine use, lightning strikes, electrical injuries, and crush injuries. Damage to muscle cells most commonly causes hypocalcemia from the deposition of calcium in necrotic muscle cells as well as calcium sequestration by the muscle sarcoplasmic reticulum. Symptoms of hypocalcemia include perioral numbness and tetany, altered mental status, and seizure. ECG manifestations of hypocalcemia include QT prolongation. There is no treatment needed for hypocalcemia in rhabdomyolysis unless it is severe or is causing symptoms such as seizure or ECG changes. The management of rhabdomyolysis involves aggressive IV fluid administration titrated to urine output in order to prevent myoglobin nephrotoxicity. Myoglobin causes the classic false-positive finding of red blood cells on urine dipstick given the cross-reactivity of myoglobin and hemoglobin on this test.

Giannoglou et al. review the pathophysiology and diagnosis of rhabdomyolysis. The authors find that hypocalcemia is the most common electrolyte derangement seen in rhabdomyolysis. The authors recommend carefully monitoring ionized calcium in patients with rhabdomyolysis.

Incorrect Answers:
Answer A: Hyperkalemia is a common electrolyte derangement that occurs in rhabdomyolysis and can cause life-threatening dysrhythmias. Initial ECG findings suggestive of hyperkalemia include peaked T waves and QRS widening. The management of hyperkalemia involves the administration of calcium chloride to stabilize cardiac membranes followed by insulin, albuterol, and bicarbonate. Severe/refractory hyperkalemia can be treated with dialysis, but this is usually not needed in rhabdomyolysis. Hyperkalemia is less common when compared to hypocalcemia in rhabdomyolysis and does not cause seizures.

Answer B: Hyperphosphatemia is common in rhabdomyolysis and occurs secondary to the release of phosphorus from damaged muscle cells. Hyperphosphatemia does not usually require treatment in rhabdomyolysis, though phosphate restriction and phosphate binders can be administered. Hyperphosphatemia can rarely lead to seizures, though this is uncommon.

Answer C: Hyperuricemia is possible in rhabdomyolysis, occurs secondary to the release of purines from injured muscle cells, and is worsened by acute kidney injury which is common in rhabdomyolysis. The treatment of hyperuricemia in rhabdomyolysis involves IV fluids, rasburicase, and allopurinol (which works slowly).

Answer E: Hyponatremia may occur after running a marathon where the individual sweats out sodium, chloride, and water but rehydrates with only water. While this is possible in this patient and his seizure could reflect a hyponatremic seizure (which usually would not spontaneously resolve and requires hypertonic saline), there is concrete evidence of rhabdomyolysis with the positive urine dipstick for red blood cells.

Bullet Summary:
Rhabdomyolysis can cause hyperkalemia, hyperphosphatemia, and hypocalcemia (the most common electrolyte disturbance).


Question: A 3-week-old boy presents to the emergency department with vomiting. His parents report that he suddenly started vomiting this morning and has shown no interest in feeding since then. They describe the vomitus as green and without any traces of blood. Prior to today, the patient was feeding, voiding, and stooling well. He was noted to have surpassed his birth weight at his last office visit 1 week ago. His temperature is 97.6°F (36.4°C), blood pressure is 78/56 mmHg, pulse is 148/min, and respirations are 44/min. On physical exam, the patient is in mild distress. He has no dysmorphic features, and his mucous membranes are dry. His abdomen is soft and distended. Bowel sounds are hypoactive. An abdominal radiograph is performed as in Figure A. Which of the following is the most appropriate next step in the diagnosis of this condition?

Answer: Upper gastrointestinal contrast series

Explanation:
This neonatal patient presents with sudden-onset bilious vomiting and an abdominal radiograph revealing a gasless abdomen, which is consistent with intestinal malrotation complicated by a midgut volvulus. The most appropriate next step in the diagnosis of intestinal malrotation is an upper gastrointestinal series.

Malrotation classically presents with bilious vomiting due to the formation of midgut volvulus. These patients will have normal development until the development of the obstruction followed by inability to feed and abdominal distention. Findings of malrotation on an upper gastrointestinal series include an abnormally placed ligament of Treitz on the right side of the abdomen and a "corkscrew" appearance of the distal duodenum. If an upper gastrointestinal contrast series confirms the diagnosis, patients should undergo surgery to reduce the volvulus in order to avoid intestinal perforation or other complications.

Adams and Stanton review the evidence regarding the diagnosis and treatment of neonatal bowel obstruction. They discuss how malrotation, jejunoileal atresia, duodenal atresia, and colonic atresia are common causes of this finding. They recommend surgical management of these conditions.

Figure/Illustration A is an abdominal radiograph demonstrating the nonspecific finding of a paucity of air in the abdomen (red circle). This is consistent with intestinal malrotation complicated by midgut volvulus.

Incorrect Answers:
Answer A: Although abdominal CT would detect intestinal malrotation, CT should be avoided in the pediatric population in light of the radiation exposure. A CT scan with oral contrast can be useful in the adult setting in order to determine if there is extravasation of fluid from the gastrointestinal tract.

Answer B: Abdominal ultrasound is the test of choice for diagnosing pyloric stenosis, which presents with non-bilious vomiting and a palpable olive mass in the abdomen. Treatment of this condition is with surgical release of the stenotic pyloric muscle.

Answer C: A contrast enema is used to differentiate between Hirschsprung disease and meconium ileus but would not be helpful in diagnosing malrotation as the midgut volvulus occurs in the small intestine. Both Hirschsprung disease and meconium ileus present in neonatal patients with bilious vomiting and failure to pass meconium in the first 48 hours of life. Treatment is with excision of the defective segment or removal of the meconium respectively.

Answer D: Rectal suction biopsy is the most accurate test to diagnose Hirschsprung disease. Although Hirschsprung disease commonly presents in neonatal patients with bilious vomiting, an abdominal radiograph in Hirschsprung disease would likely show dilation of the proximal colon.

Bullet Summary:
The most appropriate diagnostic test for malrotation in an infant is an upper gastrointestinal series, which will show the abnormal placement of the duodenum and ligament of Treitz on the right side of the abdomen.


Question: A 6-year-old boy is brought to the emergency department by his father for elbow pain. He was riding his bicycle when he fell onto his outstretched right hand. He immediately clutched his right elbow in pain and began crying. He refuses to move his elbow. He has no medical problems and takes no medications. His temperature is 98.4°F (36.9°C), blood pressure is 108/64 mmHg, pulse is 100/min, and respirations are 20/min. On exam, the boy is holding his right wrist with his left hand and cries upon palpation of a region that is 2 cm proximal to his elbow. The radial head is palpated just distal to the lateral epicondyle. He is unable to make a pincer with his right thumb and index finger. When asked to hold a pen between his right thumb and index fingers, he drops it. The radial pulse is diminished on the right. Which of the following is the most likely diagnosis?

Answer: Supracondylar humerus fracture

Explanation:
This young patient presenting with elbow pain and associated signs of anterior interosseous nerve neurapraxia (inability to make pincer, weak pincer grasp) and vascular injury (diminished radial pulse) after a fall on an outstretched hand most likely has a supracondylar humerus fracture.

Supracondylar humerus fractures are one of the most common fractures seen in the pediatric population. This site is particularly prone to fracture due to the thin bone separating the coronoid and olecranon fossae in the supracondylar region. Due to the proximity of the brachial artery and median nerve, which course anteriorly, these structures are at risk for injury. Neurapraxia of the anterior interosseous nerve, which is a pure motor branch of the median nerve, presents as motor deficits in interphalangeal (IP) joint flexion of the thumb and distal IP joint flexion of the index finger. The radial and ulnar arteries are terminal branches of the brachial artery, which if injured results in diminished distal pulses. The diagnosis is made with anteroposterior and lateral view elbow radiographs. Radiographs will demonstrate the "fat pad sign" seen as a posterior fat pad that is indicative of fracture. Management depends on fracture type but can consist of cast immobilization (if minimally displaced with no neurovascular injury) or closed reduction and percutaneous pinning (for more displaced fractures).

Micheloni et al. reviews supracondylar fractures in children. They note it is the most common elbow fracture in the pediatric population. They recommend early and correct diagnosis and management to avoid early and late complications including neurovascular impairment and malunion.

Incorrect Answers:
Answer A: Both bone forearm fracture is another common pediatric fracture sustained from a fall, involving both the radius and ulna. It can be associated with neurovascular injury depending on the plane of deformity, but the location of the pain would be in the forearm, not proximal to the elbow.

Answer B: Distal radius fracture is a common fracture after a fall on an outstretched hand mechanism of injury. Neurovascular injury is possible, though uncommon. This patient’s pain is localized around his elbow, rather than near the distal radius. Often, a deformity can be visualized on exam.

Answer C: Monteggia fracture-dislocation is characterized by a proximal ulna fracture with radial head dislocation. It is commonly caused by direct trauma to the ulna. In contrast, this patient’s radial head is located inferior to the lateral epicondyle.

Answer D: Olecranon fracture is an uncommon pediatric fracture caused primarily by a fall onto the elbow in flexion. Median nerve and brachial artery injury are unlikely, given that these structures pass anteriorly in the cubital fossa.

Bullet Summary:
Supracondylar humerus fractures are common in the pediatric population and may present with elbow pain and concomitant median nerve and/or brachial artery injury.


Question: A 65-year-old man presents to the emergency department for evaluation of left arm and leg weakness. He was walking in the park about 45 minutes prior to arrival when the patient stumbled and fell. He had sudden weakness in his left leg and was unable to grasp a handrail with his left hand. He currently takes no medications. His temperature is 98.0°F (36.6°C), blood pressure is 128/89 mmHg, pulse is 130/min, and respirations are 18/min. On exam, he has 3/5 strength in the left upper and lower extremities and a left-sided facial droop. A non-contrast CT scan of the head is performed, which suggests parenchymal ischemia in the distribution of the right middle cerebral artery. An ECG is performed, as shown in Figure A. He is given intravenous alteplase with rapid improvement in his strength deficits and facial asymmetry. Which of the following is the most appropriate long-term therapy for secondary stroke prevention for this patient?

Answer: Rivaroxaban

Explanation:
This patient presents with acute onset unilateral left-sided weakness secondary to an ischemic stroke in the right MCA in the setting of an irregularly irregular rhythm without P waves (suggesting that he had an embolic stroke secondary to atrial fibrillation). First-line primary and secondary stroke prevention in patients with atrial fibrillation involves long term anticoagulation with a direct oral anticoagulant (DOAC) such as rivaroxaban.

Atrial fibrillation is caused by uncoordinated atrial contractions, typically due to atrial enlargement, inflammation, or infiltrative disease. Atrial fibrillation can lead to the formation of a thrombus, typically in the left atrial appendage, which can embolize to the brain and lead to an ischemic stroke. For this reason, there is a low threshold to start patients on long term anticoagulation for both primary and secondary stroke prevention (risk stratification is done with the CHA2DS2-VASc score, which considers several cardiovascular risk factors, age, sex, and diabetes). First-line long term anticoagulation is a DOAC medication such as apixaban, dabigatran, rivaroxaban, or edoxaban. Delayed initiation of anticoagulation is recommended at 4-14 days after a stroke, due to the interim risk of hemorrhagic conversion. Further management of atrial fibrillation includes a rate control agent such as a beta blocker or a calcium channel blocker.

JS Alpert reviews the latest American Heart Association/American College of Cardiology guidelines regarding atrial fibrillation. The article reports that for stroke prevention in atrial fibrillation, DOACs are first-line compared to warfarin due to a decreased risk for bleeding with DOACs. In patients with moderate to severe mitral stenosis or a mechanical heart valve, warfarin is the preferred agent.

Figure/Illustration A shows an ECG with an irregularly irregular rhythm (highlighted by the spacing of blue arrows) and no discernable P waves before QRS complexes, which is characteristic of atrial fibrillation.

Incorrect Answers:
Answer A: Aspirin exerts antiplatelet adhesion effects through the inhibition of cyclooxygenase. Patients with atrial fibrillation who are at low risk for stroke (CHA2DS2-VASc score of < 1) can use aspirin monotherapy for stroke prophylaxis. This patient presented after a stroke and will require long term anticoagulation, not anti-platelet monotherapy for stroke prevention.

Answer B: Atorvastatin is an HMG-CoA reductase inhibitor, which works to lower LDL cholesterol and triglycerides, and increase HDL cholesterol. It is most useful in secondary stroke prevention in patients who have suffered a thrombotic or thromboembolic stroke secondary to atherosclerosis. This patient may have atherosclerosis and could benefit from statin therapy; however, anticoagulation for his underlying atrial fibrillation is the highest priority.

Answer C: A cardiac pacemaker is indicated in a large variety of cardiac conditions that primarily involve sinus node dysfunction or high-grade atrioventricular block. Atrial fibrillation does not typically require a pacemaker, as it is typically managed with rate control agents such as beta-blockers, calcium channel blockers, digoxin, or with electrical cardioversion. Rate control will not lower the stroke risk, and thus long-term anticoagulation is required.

Answer E: Warfarin has historically been a mainstay anticoagulant for stroke prevention in atrial fibrillation. DOACs are non-inferior to warfarin, and have a lower risk of bleeding. Note, only the initiation of warfarin requires a heparin bridge to mitigate the transient protein C deficiency that results in a temporary hypercoagulable state (often presenting as warfarin skin necrosis).

Bullet Summary:
For patients who present with an ischemic stroke secondary to a cardiac embolus from atrial fibrillation, first-line long term anticoagulation is a direct oral anticoagulant (apixaban, dabigatran, rivaroxaban, or edoxaban).


Question: A previously healthy 15-year-old boy presents to the emergency department in cardiac arrest. He was in class when he suddenly fainted and became unresponsive. His teacher began chest compressions and he has received epinephrine and defibrillation from paramedics while in transport. On arrival, the patient remains pulseless and is pronounced dead. An autopsy is performed and is notable for no clear abnormalities. The patient’s laboratory studies were unremarkable from a visit to the pediatrician 3 weeks ago. A previous ECG is seen in Figure A. Which of the following is the most likely underlying etiology of this patient’s death?

Answer: Short QT syndrome

Explanation:
This healthy pediatric patient is presenting with cardiac arrest and an ECG demonstrating a short QT segment. Short QT syndrome is lethal and can lead to cardiac arrest in young, otherwise healthy patients.

Short QT syndrome is an inherited condition that is caused by ion channel mutations (the most common identified mutation is a mutation in the cardiac myocyte potassium channel). There is no strict criteria for short QT syndrome, but the QT segment is often < 320 ms. Patients are usually young and healthy, and it is very common for the first presentation of this disease to be syncope or sudden cardiac death. ECG features suggestive of this condition include a short QT interval (without a clearly defined value but often < 360 ms) that is fixed (does not change with exercise or rest), peaked T waves, short or even absent ST segments, and episodes of atrial fibrillation or ventricular fibrillation in a patient in whom this would not be expected (such as a young patient). The only effective intervention is the placement of an implantable cardioverter-defibrillator.

Bjerregaard and Gussak discuss short QT syndrome. They note it is a heritable condition of the conduction system of the heart that can lead to lethal dysrhythmias. They discuss the management of this condition and recommend an implantable cardioverter-defibrillator.

Figure/Illustration A is an ECG demonstrating a short QT segment (red arrow). Note the T waves appear peaked which can be seen in this syndrome. This may suggest hyperkalemia, but this patient’s labs were normal at his appointment when the ECG was taken.

Incorrect Answers:
Answer A: Complete heart block is more common in elderly patients with acute coronary syndrome and presents with regular P-P and R-R intervals with complete P-R dissociation. It may cause syncope but is not associated with short QT syndrome. Management involves the placement of a pacemaker.

Answer C: Torsades des pointes is associated with a prolonged QT segment that progresses to the classic twisting of the QRS complexes around an isoelectric baseline. It can lead to cardiac arrest and requires immediate cessation of QT-prolonging medications and administration of magnesium. Note that this patient’s QT segment is short rather than long.

Answer D: Ventricular fibrillation presents with disorganized electrical activity with no discernible rhythm. While this patient may have arrested from ventricular fibrillation, the most likely underlying etiology for his cardiac arrest given his age, ECG, and risk factors is an underlying condition such as short QT syndrome. For this reason, short QT syndrome is a better answer.

Answer E: Ventricular tachycardia could also occur in short QT syndrome and may have caused this patient’s cardiac arrest. It presents with a monomorphic wide complex tachycardia that may cause arrest. Unstable patients require cardioversion while pulseless patients require defibrillation. Note that if this patient arrested from ventricular tachycardia, it was likely secondary to short QT syndrome.

Bullet Summary:
Short QT syndrome is a rare but possible diagnosis in young, healthy patients who present with recurrent syncope or cardiac arrest.


Question: A 72-year-old man presents to his primary care physician with weakness. He has felt very weak every morning with his symptoms persisting throughout the day. He notes minor improvement when he rides his bike but otherwise has not noticed any change in his symptoms with rest or ibuprofen use. The patient has lost 12 pounds recently and has had a chronic cough. The patient lives alone and drinks 7 alcoholic beverages per day and smokes 1-2 packs of cigarettes per day for the past 40 years. His temperature is 99.5°F (37.5°C), blood pressure is 177/108 mmHg, pulse is 93/min, respirations are 17/min, and oxygen saturation is 92% on room air. A chest radiograph is ordered as seen in Figure A. Which of the following diagnostic tests would most likely elucidate the cause of this patient's weakness?

Answer: Electromyography

Explanation:
This patient who presents with weakness that improves with activity in the setting of a lung mass most likely has Lambert-Eaton syndrome. The most appropriate diagnostic test to confirm this syndrome is electromyography.

Small cell lung cancer presents with fatigue, weight loss, cough, and a coin lesion on chest radiograph typically in a smoker. A common paraneoplastic syndrome in small cell lung cancer is Lambert-Eaton syndrome which presents with muscle weakness that improves with activity and worsens with rest. Activity improves symptoms due to accumulation of calcium with exercise which allows for acetylcholine release. This occurs secondary to antibodies against presynaptic calcium channels which decrease acetylcholine release. The diagnosis of Lambert Eaton syndrome can be confirmed with electromyography. Treatment includes addressing the underlying lung tumor.

Kesner et al. review the diagnosis and etiology of Lambert-Eaton syndrome. They discuss how this disease is associated with lung cancer. They recommend making the diagnosis using electrophysiologic studies.

Figure/Illustration A is a chest radiograph with a coin lesion in the left lung field (red circle). This finding is suggestive of small cell lung cancer.

Incorrect Answers:
Answer A: Blood laboratory tests could assess for multidrug resistance 1 protein (MDR-1 aka P-glycoprotein or ABCB1) which predicts resistance to chemotherapy for small cell lung cancer; however, it would not further elucidate this patient's muscle weakness.

Answers 2 & 4: CT scan of the chest and lung biopsy would further elucidate this patient's small cell lung cancer; however, it would not explain his weakness that improves with activity. In the setting of an elderly smoker with fatigue and weight loss and a coin lesion, the diagnosis of lung cancer is essentially established.

Answer E: Muscle biopsy would be the most accurate diagnostic test for dermatomyositis, polymyositis, and inclusion body myositis; however, it would not assess for conditions such as myasthenia gravis and Lambert-Eaton syndrome.

Bullet Summary:
Electromyography is the diagnostic test of choice for Lambert-Eaton syndrome.


Question: A 28-year-old man is brought to the emergency department by helicopter after a high speed motorcycle crash. He was intubated and 2 large bore IVs were placed in the field with administration of 2 liters of lactated ringer's solution while en route. On arrival to the emergency department, his temperature is 98.6°F (37.0°C), pulse is 130/min, blood pressure is 80/50 mmHg, respirations are 22/min, and oxygen saturation is 97%. Examination reveals an ill-appearing intubated patient. Endotracheal tube placement is confirmed with end tidal CO2, and bilateral breath sounds are present. No external bleeding or wounds are noted on exam. Pulses are present in all extremities but are weak and rapid. Significant bruising is noted over the abdomen. The pelvis is stable. Infusion of packed red blood cells is initiated. Which of the following is the most appropriate next step in management?

Anterior-posterior and lateral radiographs of the abdomen and pelvis

Answer: FAST exam

Explanation:
This patient with hemodynamic instability and abdominal bruising after a high speed motorcycle crash likely has shock secondary to blood loss. The first step in management of patients with blunt trauma and hemodynamic instability is a focused assessment with sonography for trauma (FAST exam)

For any patient with blunt or penetrating trauma, the first step in management is an evaluation of airway, breathing, and circulation. This is referred to as the primary survey and includes the verification of endotracheal tube placement, auscultation of bilateral breath sounds, and assessment of external wounds or bleeding. This is followed by the secondary survey which involves a detailed head to toe inspection for injuries. Blunt abdominal trauma with bruising as well as hemodynamic instability warrants a FAST exam. The FAST exam visualizes the heart chambers and pericardium, left upper quadrant (spleen, splenorenal recess), right upper quadrant (Morrison pouch) and the rectovesical (males) or rectouterine (females) pouch. The extended FAST exam (eFAST) includes an examination of the lungs as well to assess for pneumothorax or hemothorax. Hemodynamically unstable patients with free fluid identified in the abdomen on initial FAST exam should proceed directly to the operating room for emergent surgical intervention with ongoing volume resuscitation. Patients with hemodynamic instability and a negative FAST exam should be evaluated for sources of bleeding elsewhere such as the pelvis.

Barloon et al. review diagnostic imaging in the evaluation of blunt abdominal trauma. Blunt abdominal trauma is a common cause of death and injury, leading to hemodynamic instability. Intra-abdominal imaging is especially important in comatose or sedated (intubated) patients who are unable to provide a history or provide a reliable physical examination. In stable patients, CT of the abdomen often has a role in deciding whether to pursue observation versus surgical intervention.

Stengel et al. evaluate emergency ultrasound-based algorithms for diagnosing blunt abdominal trauma. The systematic review showed that ultrasound-based pathways reduced the number of CT scans obtained. Use of ultrasound can enhance the speed of the primary assessment and cut costs. However, the authors conclude that there is insufficient evidence to promote justification of ultrasound-based pathways for the evaluation of blunt abdominal trauma in terms of patient outcomes.

Incorrect Answers:
Answer A: AP and lateral radiographs of the abdomen and pelvis may be useful for identifying pelvic fracture or intraperitoneal free air. However, this patient's presentation is suggestive of abdominal trauma warranting FAST exam.

Answer B: CT scan of the abdomen and pelvis with contrast would be appropriate for evaluation of blunt abdominal trauma in a patient that is hemodynamically stable. However, this patient's vital signs indicate hemodynamic instability.

Answer C: Diagnostic peritoneal lavage is no longer commonly used in the evaluation of blunt abdominal trauma.

Answer E: Norepinephrine infusion would not be appropriate for this patient with shock secondary to blood loss. Resuscitation for this patient should be achieved with transfusion of blood products.

Bullet Summary:
The most appropriate initial step in management for hemodynamically unstable patience with blunt abdominal trauma is a FAST exam.


Question: A 55-year-old man presents to his primary care physician with fatigue, malaise, and a painful rash. The patient states that his symptoms have been worsening over the past week. He also has experienced abdominal pain and diarrhea. He has a medical history of obesity and smokes regularly. His temperature is 97.5°F (36.4°C), blood pressure is 142/82 mmHg, pulse is 85/min, respirations are 15/min, and oxygen saturation is 98% on room air. Physical exam is notable for an erythematous rash with papules and plaques on the patient's face, torso, and extremities. He states that the rash is painful. A fingerstick blood glucose is unable to accurately read his blood glucose and gives a reading of > 500 mg/dL. Which of the following is the most likely underlying pathophysiology of this patient’s condition?

Answer: Alpha cell tumor

Explanation:
This patient is presenting with necrolytic migratory erythema (a painful, erythematous rash with papules and plaques) with gastrointestinal symptoms (abdominal pain and diarrhea) and hyperglycemia, which are concerning for a glucagonoma. A glucagonoma is a tumor of the alpha cells.

A glucagonoma is a tumor of the alpha cells of the pancreas. This tumor pathologically secretes glucagon leading to profound hyperglycemia that is refractory to the normal treatments for diabetes. Patients also present with a classic rash termed necrolytic migratory erythema which presents with painful, erythematous papules and plaques. Other findings include gastrointestinal symptoms including anorexia, abdominal pain, and diarrhea. Hematologic findings include a normocytic, normochromic anemia. The diagnosis can be supported with a glucagon level, which will be elevated. Imaging of the pancreas by CT or MRI (more accurate) can further support the diagnosis.

Zandee et al. review glucagonoma. They note the presentation and symptoms associated with a glucagonoma, including the classic rash and elevated blood glucose. They recommend considering this diagnosis in patients who present with rash and hyperglycemia refractory to typical treatments.

Incorrect Answers:
Answer B: Beta-cell destruction is the pathophysiology of type I diabetes mellitus which presents with polydipsia, polyuria, weight loss, and hyperglycemia (typically in a pediatric patient). It can progress to diabetic ketoacidosis which presents with hyperglycemia, an anion gap acidosis, altered mental status, and Kussmaul respirations.

Answer C: Beta-cell tumor describes an insulinoma, which would present with hypoglycemia refractory to glucose administration. This condition is caused by increased release of insulin. The diagnosis should be suspected in the setting of hypoglycemia, an elevated insulin level, and an elevated C-peptide level. Imaging of the abdomen/pancreas with an MRI will reveal the insulin-secreting mass.

Answer D: Hypercortisolism can cause Cushing syndrome which presents with hyperglycemia, obesity, striae, limb/muscle atrophy, mood changes, and hypertension. A buffalo hump and moon faces may also be seen. This condition can either be from endogenous ACTH production or cortisol production or can be from exogenous steroid use.

Answer E: Insulin resistance is the pathophysiology of type 2 diabetes mellitus and presents with obesity, hyperglycemia, and an elevated hemoglobin A1c. The mainstay of management is weight loss, though medications such as metformin, sulfonylureas, or insulin are often needed.

Bullet Summary:
A glucagonoma is a tumor of the alpha cells of the pancreas that hypersecretes glucagon.


Question: A 67-year-old man presents with a recurrent episode of syncope. He states that this has happened to him multiple times, particularly when he changes body position from sitting to standing, exerts himself, or turns his head quickly. He says that he notes numbness, vertigo, and sometimes even trouble with speaking immediately prior to fainting. The episodes usually last 1-5 minutes. When he wakes up, he is mildly confused but typically returns to baseline within a minute. The patient has a past medical history of diabetes, dyslipidemia, and hypertension. His temperature is 98.5°F (36.9°C), blood pressure is 153/89 mmHg, pulse is 90/min, respirations are 11/min, and oxygen saturation is 97% on room air. The patient's neurological exam is unremarkable. However, when he is asked to stand up and start walking, he experiences the same numbness and tingling and feels like he may faint. Which of the following is the most likely diagnosis?

Answer: Blood vessel narrowing

Explanation:
This elderly patient with risk factors for vascular disease (diabetes, dyslipidemia, hypertension) is presenting with episodes of dizziness, vertigo, numbness/tingling, dysarthria, and syncope, which seem to be provoked by standing rapidly and changing head position. This is concerning for vertebrobasilar syndrome, caused by blood vessel narrowing.

Vertebrobasilar syndrome is caused by narrowing (via causes such as atherosclerosis, dissection, or congenital narrowing among others) of the vertebrobasilar vascular system. It is a common cause of syncope that may be worsened by changes in head position or standing rapidly. Other unique features include numbness/tingling, a sensation of vertigo, nausea, vomiting, dysphagia, and dysarthria. Note the episodes of syncope in this condition are intermittent and specifically provoked and do not have lasting/permanent neurological deficits in contrast to a stroke. Management is first centered on vascular imaging which may include a CTA head/neck or an MRA head/neck. Further care depends on the symptoms present but typically involves smoking cessation, glycemic control, blood pressure control, aspirin, and a statin.

Xuan-Ting et al. review posterior circulation strokes which occur more frequently in patients with atherosclerosis of the vertebrobasilar system. They note that MRI is one of the most accurate tests for assessing posterior circulation strokes which may present with dizziness and syncope. It is far superior to CT imaging. For this reason, they recommend that CT imaging alone cannot definitively rule out a posterior circulation stroke.

Incorrect Answers:
Answer B: Cardiac dysrhythmias such as ventricular tachycardia can cause sudden onset and offset syncope without prodromal symptoms. The differentiating feature of this form of syncope is the rapid onset and offset in a high-risk patient. The diagnosis can be confirmed with an ECG; however, many patients will require prolonged observation on telemetry.

Answer C: Seizure presents with impaired consciousness, tonic-clonic activity, and a post-ictal state which gradually improves over hours. The lactate may be elevated after a seizure, and the prolactin level is a more specific indicator of a seizure. However, the diagnosis is most appropriately made based on history, exam, and EEG.

Answer D: Stroke involving the vertebrobasilar system may cause syncope in addition to ongoing dizziness and vertigo with ataxia. However, this patient's symptoms seem to be positional and have entirely resolved; thus, a stroke is unlikely. He is at higher risk of stroke given his vertebrobasilar insufficiency and an MRI should still be performed in this patient.

Answer E: Vagal event presents with a warm prodrome with palpitations, flushing, and syncope. Muscle twitching (but no tonic-clonic activity) may be seen. Patients may wake up slightly confused but return to baseline within seconds.

Bullet Summary:
Vertebrobasilar insufficiency may present with positional episodes of syncope caused by insufficient blood flow through the vertebrobasilar blood vessels.


Question: A 30-year-old man presents to the emergency department with diarrhea. He states he has had profuse, watery diarrhea for the past 24 hours. He notes that eating and drinking make him defecate more, thus he has been refraining from drinking. He is otherwise healthy and takes no medications. His temperature is 97.7°F (36.5°C), blood pressure is 84/64 mmHg, pulse is 130/min, respirations are 17/min, and oxygen saturation is 99% on room air. Physical exam reveals dry mucous membranes with an otherwise benign exam. The patient is given 1L of normal saline and drinks 1L of oral fluids. His blood pressure is subsequently 120/70 mmHg and pulse 95/min. Which of the following is the most appropriate next step in management?

Answer: Rest and oral rehydration

Explanation:
This patient is presenting with a likely diarrheal illness given he has profuse, watery diarrhea and his vitals normalized with oral and IV hydration. Since the patient is young and healthy, oral hydration and rest are all that is needed for management.

Diarrheal illness is a common chief complaint with variable workups pending on the patient's clinical status. Young, healthy, non-immunosuppressed patients who can tolerate an oral diet require only reassurance and oral hydration, as most cases of viral and bacterial diarrhea will resolve on their own. Moreover, most cases of diarrhea are caused by viral etiologies which simply require supportive therapy. This is even true in bacterial diarrhea as long as the patient's vitals normalize and they can tolerate an oral diet. It is important to consider inflammatory causes of diarrhea (such as ulcerative colitis or Crohn disease) as this would change the workup and management.

Schiller et al. discuss different types of diarrhea. They review the management and diagnosis of diarrhea and its different forms, including chronic forms. They recommend noting the difference between different causes and working up and treating them appropriately.

Incorrect Answers:
Answer A: Ciprofloxacin is an antibiotic that can be used for bacterial/infectious diarrhea. It should not be given in young, healthy patients and would only be indicated in the setting of bacterial diarrhea in ill patients, patients with persistent symptoms, or patients who are immunosuppressed. Bacterial diarrhea would present with fever, abdominal pain, and bloody/purulent diarrhea.

Answer C: Stool culture should not be empirically performed in young, well-appearing patients. It may be performed in hospitalized patients who are more ill or in patients who are going to start antibiotic therapy. It may also be performed in patients with persistent diarrhea.

Answer D: A stool ova and parasite study would not be performed unless there was a suggestive history or exposure (such as drinking unfiltered water) in the setting of fatty, foul-smelling diarrhea. This would raise suspicion for Giardia lamblia which would be treated with metronidazole.

Answer E: Stool PCR for viral etiologies of diarrhea is not useful as the management of viral diarrhea is supportive therapy in most cases. On occasion, it may be performed in critically ill patients to determine the etiology of their symptoms. It should not be performed routinely.

Bullet Summary:
Healthy patients with limited diarrheal illness require supportive therapy only (in particular, oral hydration) and do not need more invasive diagnostic tests.


Question: A 23-year-old woman presents to the emergency department for evaluation of fever and chills over the last several days along with a progressive rash and diarrhea. She had nasal septoplasty performed 1 week prior and has had nasal packing in place since that time. Her rash has progressed and the skin on her hands is "peeling." She has no significant medical history and takes no medications. Her temperature is 102°F (38.9°C), blood pressure is 84/54 mmHg, pulse is 160/min, respirations are 22/min, and oxygen saturation is 99% on room air. Exam reveals an ill-appearing woman. A diffuse, macular, erythematous rash is noted with desquamation over the patient's hands as shown in Figure A. Bilateral conjunctivitis is noted. The patient's nasal packing is removed revealing copious, foul-smelling, purulent discharge. Which of the following pathogens is likely responsible for this patient's condition?

Answer: Staphylococcus aureus

Explanation:
This patient with fever, diarrhea, and a diffuse, erythematous rash with prolonged nasal packing in place likely has developed toxic shock syndrome. Toxic shock syndrome occurs most commonly due to infection with Staphylococcus aureus.

Toxic shock syndrome (TSS) occurs due to infection with Staphylococcal or Streptococcal species that produce "super-antigen" toxins, such as TSST-1 produced by S. aureus. These toxins bind directly to the MHC-II receptor on T cells with high affinity causing a massive, sustained cytokine release. The result is a "cytokine storm" causing an intense inflammatory reaction and distributive shock. These infections arise in the setting of a retained tampon or retained nasal packing following nasal surgery; however, this is not always the case. The clinical presentation of TSS is characterized by fever, nausea, vomiting, diarrhea, conjunctivitis, and a diffuse "sunburn-like" rash. Desquamation of the palms and soles typically occurs during recovery, 1-2 weeks after the acute phase of the illness. The initial management of TSS begins with broad spectrum antibiotic therapy. Typical regimens include vancomycin, cefepime, and clindamycin. The initial antibiotic regimen should cover methicillin-resistant Staph aureus. Clindamycin is always included due to its ability to suppress bacterial protein production, therefore limiting the production of bacterial toxins. Once a causative organism is identified, antibiotic therapy may be narrowed, though clindamycin is usually administered for the duration of treatment.

Figure A is the classic generalized and erythematous macular/desquamating rash of toxic shock syndrome.

Incorrect Answers
Answer A: Borrelia burgdorferi is a spirochetal bacteria that causes Lyme disease. A erythematous, bulls-eye shaped rash would be expected.

Answer B: Neisseria meningitidis causes meningococcemia and meningitis. Fever is common, although a purpuric rash and signs of meningeal irritation would be expected. Patients are often profoundly unstable.

Answer C: Rhinovirus is the viral pathogen most commonly responsible for the common cold that causes minor symptoms including a cough, runny nose, fever, and aches.

Answer D: Rickettsia rickettsii causes rocky mountain spotted fever which presents with a high fever, headache, malaise, and a centripetal maculopapular rash that starts on the extremities and migrates to the trunk. It is a tick-borne illness.

Bullet Summary:
Toxic shock syndrome classically develops in patients with prolonged use of nasal packing, and presents with fever, diarrhea, a diffuse erythematous rash, and shock.


Question: Figure A is the lateral radiograph of a 44-year-old male who sustained a fall on his outstretched hand while rollerblading. The patient reports pain localized to the posterior elbow and refuses to attempt elbow extension secondary to pain and swelling. Which of the following is the most likely diagnosis in this patient?

Answer: Triceps rupture

Explanation:
The flake sign, as seen in Figure A is pathognomonic of a triceps tendon rupture.

Tricep tendon ruptures are rare injuries to the elbow extensor mechanism that most commonly occur as a result of forceful elbow contraction. Diagnosis can be made clinically, as patients with complete ruptures are unable to extend the elbow against gravity. An MRI may be useful in the diagnosis in patients whom are too painful to examine or who may have partial tears of the triceps tendon. Surgical repair is indicated in patients with complete rupture or in those with >50% tears and significant weakness.

Yeh et al. review distal triceps ruptures. They report that these injuries are commonly caused by a fall on an outstretched hand or a direct blow. If identifiable on plain radiograph a flake sign or avulsion of the olecranon tip will be appreciated. They conclude that diagnosis may be difficult initially in a painful elbow, however, a combination of plain radiographs and MRI can assist in making the correct diagnosis.

Beazley et al. review distal biceps and triceps injuries. They report that these injuries most commonly occur in middle-aged males as a result of eccentric loading of the tendon. They conclude that patients who undergo early diagnosis and surgical treatment can expect to have excellent outcomes.

Keener et al. review distal tricep tendon injuries. They report that most complete tears are treated surgically in medically fit patients. Partial-thickness tears are managed according to the tear severity, functional demands, and response to conservative treatment. They conclude that anatomic footprint repair of the triceps with optimal tendon to bone healing results in an acceptable functional outcome.

Figure A is the lateral radiograph of an elbow demonstrating a flake sign from the olecranon tip indicative of a triceps rupture.

Incorrect Answers:
Answer A: The patient does not show significant elbow degenerative disease on plain radiographs.
Answer C: Olecranon bursitis is not likely to worsen acutely after a fall, nor are there any other indications of this diagnosis in the present patient.
Answer D: While lateral collateral ligament tears may occur following a fall on an outstretched arm, there is no indication that an elbow dislocation occurred here and based on current radiographs a triceps rupture is more likely.
Answer E: Anconeus avulsions fractures are identified as lateral epicondyle fractures.


Question: A 46-year-old woman presents to her primary care doctor to request a referral to ophthalmology. Her vision has been steadily declining over the past 2 years and she thinks she needs a prescription for glasses. She further complains that her lips and feet feel numb. Her medical history is notable for medullary thyroid cancer status post total thyroidectomy. Her periods are regular. She enjoys a diverse diet and takes levothyroxine. Her blood pressure is 110/70 mmHg, pulse is 80/min, and respirations are 12/min. She is alert and oriented. Her pupils are equal, round, and reactive to light, but appear opacified. Extraocular movements are intact, albeit slow. Her visual acuity is decreased bilaterally. The remainder of her physical exam is unremarkable. Her basic metabolic panel is shown below: Na+: 139 mEq/L Cl-: 100 mEq/L K+: 4.9 mEq/L HCO3-: 25 mEq/L BUN: 10 mg/dL Glucose: 110 mg/dL Creatinine: 0.8 mg/dL Thyroid-stimulating hormone: 1.5 µU/mL Ca2+: 7.0 mEq/L Phosphorus: 6.5 mEq/L Albumin: 3.6 mg/dL The patient's ECG is shown in Figure A. What is the most likely cause of this presentation?

Answer: Iatrogenic hypoparathyroidism

Explanation:
This patient who presents with cataracts and a prolonged QTc interval on ECG most likely has symptomatic hypocalcemia secondary to the surgical removal of all of her parathyroid glands (iatrogenic hypoparathyroidism).

Thyroid surgery may mandate the removal of parathyroid glands if there is evidence of malignant invasion. One parathyroid gland is enough to maintain eucalcemia, but accidental/intentional removal of all the glands is possible. Less common causes are autoimmune parathyroid destruction or parathyroid infiltration by disorders like sarcoidosis or Wilson disease. Many patients are asymptomatic, but chronic hypocalcemia is associated with increased phosphate levels, prolonged QT interval, Parkinsonian signs, cataracts, and cognitive impairment. Severe, acute hypocalcemia can present with tetany, papilledema, and seizures. Treatment is with calcium and parathyroid hormone replacement.

Clarke et al. review the evidence regarding the diagnosis and etiologies of hypoparathyroidism. They discuss how the most common cause is post-surgical. They recommend obtaining genetic testing in cases where the etiology is unclear.

Figure/Illustration A shows an ECG with a prolonged QTc interval at approximately 500 msec (blue circle).

Incorrect Answers:
Answer A: This patient is mildly hyperkalemic, but her symptoms and signs are not associated with hyperkalemia. Patients with hyperkalemia present with heart palpitations, shortness of breath, chest pain, nausea, or vomiting. ECG will demonstrate peaked T waves.

Answer C: The patient is on levothyroxine with appropriate TSH levels. Hypothyroidism is not associated with QT prolongation. Patients with hypothyroidism will present with cold intolerance, delayed responsiveness, and myxedema coma. Treatment is with increasing the levothyroxine dose.

Answer D: Multiple endocrine neoplasia is associated with medullary thyroid cancer, but this patient has no evidence of additional organ disease. Other signs of multiple endocrine neoplasia include pancreatic tumors, pheochromocytoma, or a Marfanoid habitus. Treatment is with surgical excision of tumors.

Answer E: This patient most likely has a biological reason for her symptoms, so somatization is less likely. Patients with somatizing disorders have psychological distress that manifests as physical symptoms. These patients will not have organic correlates of disease such as abnormal ECG results.

Bullet Summary:
Iatrogenic hyperparathyroidism after the removal of the thyroid gland is the most common cause of hypocalcemia.


Question: A 35-year-old G0P0000 woman presents to her gynecologist with complaints of irregular menstruation. She has had only 2 periods in the last year. She feels flushed without provocation and is experiencing occasional dyspareunia with post-coital spotting. She has also had more frequent headaches than usual. The patient has a medical history of Hashimoto thyroiditis and takes levothyroxine daily. Her mother has type 1 diabetes mellitus. Her temperature is 98.5°F (36.9°C), pulse is 70/min, blood pressure is 118/76 mmHg, and respirations are 13/min. Cardiopulmonary and abdominal exams are unremarkable. The patient has Tanner 5 breasts and pubic hair. A pelvic exam reveals a normal cervix, an anteverted uterus without tenderness, and no adnexal masses. The following laboratory studies are performed: Serum: Thyroid stimulating hormone (TSH): 28 µIU/mL (9-30 µIU/mL) Cycle day 3 follicle stimulating hormone (FSH): 49 mIU/mL (4.7-21.5 mIU/mL) Cycle day 3 estradiol: 8 pg/mL (27-123 pg/mL) Prolactin: 14 ng/mL (4-23 ng/mL) Testosterone: 42 ng/dL (15-70 ng/dL) Which of the following is the most appropriate next step in management?

Estradiol patch with oral medroxyprogesterone

Answer: Estradiol patch with oral medroxyprogesterone

Explanation:
This patient presents with oligomenorrhea, hot flashes, and dyspareunia, and her labs are notable for a high FSH and low estradiol, most consistent with premature ovarian insufficiency/failure (POI). The most appropriate next step in management is an estradiol patch with oral medroxyprogesterone.

POI is defined by the depletion or dysfunction of ovarian follicles, resulting in oligomenorrhea or amenorrhea with symptoms of menopause (hot flashes, vaginal atrophy and dryness, mood swings, etc.) in women under age 40. The cause is unclear and thought to be autoimmune. The main diagnostic markers are a high FSH and low estradiol at the start of the follicular phase. Patients require estrogen supplementation until around age 50, as low estrogen increases the risk of coronary artery disease, osteoporosis, and sexual dysfunction. Vaginal gel or a transdermal patch is the first-line option, but both must be used in conjunction with medroxyprogesterone to avoid unopposed estrogen and the risk of endometrial hyperplasia.

Tsiligiannis et al. review the evidence regarding the outcomes of patients with POI. They discuss how this diagnosis is made in patients younger than the age of 40. They recommend closely managing the cardiovascular risk factors associated with this disease.

Incorrect Answers:
Answer A: Brain MRI would be useful for evaluating for the presence of a prolactinoma, which could cause the headaches and oligomenorrhea seen in this patient. However, her prolactin level is normal, and she has no visual disturbances (e.g., bitemporal hemianopsia), making this study less relevant.

Answer B: The combined oral contraceptive has both estrogen and progesterone, but the doses are higher than those needed for hormone replacement. For this reason, it is generally not considered first-line for the treatment of POI.

Answer D: Increasing this patient’s levothyroxine dose is unnecessary, as her TSH level is within the normal range. Furthermore, while hypothyroidism may cause menstrual irregularities and temperature dysregulation, it is unlikely to cause vaginal dryness and subsequent dyspareunia.

Answer E: Vaginal estradiol gel is an effective method of estrogen replacement in women with POI. However, used alone it may increase the risk of endometrial hyperplasia and cancer, so it should only be used in combination with a systemic progesterone.

Bullet Summary:
Premature ovarian insufficiency should be treated with estrogen and progesterone replacement.


Question: A 27-year-old man presents to his primary care physician for exposure to toxic materials. The patient states that when he left for work this morning he was certain that he had closed the door to his pantry. Upon returning home, he saw that the door to his pantry was wide open. The patient is certain that his neighbors have been tampering with his food and potentially poisoned him. He further states that he knows they have been trying to break into his house and steal his things. He has tried multiple times to get them evicted from the building to no avail. It is for this reason that he is certain that they are trying to get their revenge upon him. His temperature is 98.6°F (37°C), blood pressure is 115/71 mmHg, pulse is 72/min, and respirations are 12/min. The physician performs a physical exam and tells the patient that he thinks there is nothing to be concerned about, but that he should call him or come into the office if he experiences any symptoms. The patient is outraged at this news and requests a competent doctor who is not colluding with his enemies. He storms out of the office angrily, stating that he deserves the best in medical care. Which of the following is the most likely disorder that this patient is suffering from?

Answer: Paranoid personality disorder

Explanation:
This patient is presenting with a history of mistrust and suspicion of others without frankly psychotic features suggesting a diagnosis of paranoid personality disorder.

Paranoid personality disorder is a cluster A personality disorder that is genetically associated with schizophrenia. These patients present with a pervasive mistrust of others based on little or no evidence. These patients are inclined to believe others have bad intentions that are directed toward them. They are often odd, very emotionally cold, and typically are involved in frequent litigations. Patients can be hard to manage though they often benefit from cognitive behavioral therapy. Anxiolytics may also be helpful in calming these patients.

Triebwasser et al. review the evidence regarding the diagnosis of paranoid personality disorder. They discuss how there is relatively little research on these patients because it is difficult to recruit them for studies. They recommend considering the removal of this diagnosis and replacing it with a domain of paranoia.

Incorrect Answers:
Answer A: Borderline personality disorder presents with emotional instability, unstable relationships, and recurrent self-harm behaviors. These patients will typically demonstrate the defense mechanism of splitting (seeing things as all good or all bad). Dialectical behavioral therapy can be used in order to help these patients mitigate self-injurious behaviors.

Answer B: Intermittent explosive disorder presents with sudden episodes of aggression out of proportion to the stressor. This patient’s response is a result of his paranoia rather than an excessive response to reasonable stimuli. Cognitive behavioral therapy can be used in order to help these patients control their emotional outbursts.

Answer C: Narcissistic personality disorder presents with a grand sense of self-importance and preoccupation with success and admiration. These individuals are typically selfish and lack empathy. Though this patient’s demand for the best medical care may be reflective of narcissistic personality disorder, the majority of his behaviors point more toward a diagnosis of paranoid personality disorder.

Answer E: Schizoid personality disorder presents in patients with isolated and emotionally restricted behavior. These patients are typically alone but enjoy being alone and often seem disinterested in others. These patients typically do not seek relationships and do not seek therapy as they are not bothered by their behaviors.

Bullet Summary:
Paranoid personality disorder presents with mistrustful behavior, suspicion of others, oddness, emotional coldness, and they are typically involved in many litigations.


Question: A 27-year-old woman presents to the emergency department with altered mental status. Her boyfriend found her at home next to a suicide note and brought her into the emergency department. According to her boyfriend, the patient has a medical history of bipolar disorder for which she takes lithium, as well as chronic lower back pain for which she sees a pain specialist. Her temperature is 100.5°F (38.1°C), blood pressure is 102/78 mmHg, pulse is 127/min, respirations are 19/min, and oxygen saturation is 99% on room air. An ECG is performed as seen in Figure A. Which of the following findings is also likely to be present at some point in this patient’s course?

Answer: Urinary retention

Explanation:
This patient is presenting after a suicide attempt with an unknown overdose and is confused, febrile, tachycardic, and has QRS widening on ECG. This combination of symptoms is highly concerning for a tricyclic antidepressant (TCA) overdose which can cause an anticholinergic toxidrome and urinary retention.

Tricyclic antidepressants (TCAs) were once a mainstay in the treatment of depression before the advent of selective serotonin reuptake inhibitors (SSRIs) and serotonin–norepinephrine reuptake inhibitors (SNRIs). They are sometimes still used for depression and neuropathic pain. In overdose, TCAs block sodium channels in the heart and cause a pathognomonic QRS widening. Sodium bicarbonate should be administered until the QRS duration normalizes. TCAs also have anticholinergic properties and can cause an anticholinergic toxidrome including delirium, confusion, constipation, decreased bowel sounds, urinary retention, dry, warm, and flushed skin, and fever. Although physostigmine is typically the antidote of choice for an anticholinergic toxidrome, it is avoided in TCA toxicity due to the theoretical concern for inducing a cardiac arrest.

Urquhart et al. studied the utility of tricyclic antidepressants in the treatment of chronic lower back pain. They found no significant difference in pain reduction compared to placebo. They recommend further study of the potential benefits of TCAs, independent of sleep improvement, for the treatment of lower back pain.

Figure/Illustration A is an ECG demonstrating QRS widening (note how long the red lines are which demarcate the QRS duration) which is highly concerning for TCA overdose.

Incorrect Answers:
Answer A: Diaphoresis, tachycardia, increased bowel sounds, and agitation would be seen in a sympathomimetic toxidrome from drugs like cocaine or amphetamines. Rather, dry, flushed skin would be seen in an anticholinergic toxidrome.

Answer B: Jaundice, nausea, vomiting, and abdominal pain would be seen in acetaminophen overdose which can cause fulminant liver failure. It is also possible that patients may initially be asymptomatic in acetaminophen overdose, and a high level of suspicion must be maintained for this diagnosis. A serum acetaminophen level should be drawn in any patient suspected of overdose.

Answer C: Miosis, bradypnea, decreased bowel sounds, and somnolence would be seen in an opioid toxidrome. Rather, dilated and minimally responsive pupils would be seen in an anticholinergic toxidrome.

Answer D: Wheezing, bronchorrhea, urinary incontinence, fecal incontinence, confusion, and drooling would be seen in a cholinergic toxidrome from agents such as organophosphates or nerve gases like sarin. None of these symptoms are seen in this patient.

Bullet Summary:
A tricyclic antidepressant overdose can cause QRS widening on ECG as well as an anticholinergic toxidrome (dry, flushed skin, constipation, decreased bowel sounds, urinary retention, and altered mental status).


Question: A 40-year-old south asian man presents to a primary care provider with a chronic cough that is worse at night. He has had the cough for several years but it has been getting worse over the last few months. He recently moved to the United States to work in construction. He has lost 10 pounds in the last 3 months along with darker stools which he believes is caused by a Western diet. He denies any difficulty swallowing or feeling of food getting stuck in his throat. He drinks alcohol 1-2 times per week and has never smoked. He denies any family history of cancer. His temperature is 98.6°F (37°C), blood pressure is 114/72 mmHg, pulse is 82/min, and respirations are 12/min. On physical exam, his lungs are clear to auscultation bilaterally without wheezing. His abdomen is soft and non-distended. He has no tenderness to palpation and bowel sounds are present. Which of the following is the most appropriate next step in management?

Answer: Upper endoscopy

Explanation:
This patient presents with a chronic cough that is worse at night, which is consistent with gastroesophageal reflux disease (GERD). In light of this patient’s new weight loss and melena, the most appropriate next step in management would be upper endoscopy to rule out cancer.

GERD may present as a chronic or nighttime cough, substernal or epigastric pain, regurgitation, nausea, or bitter taste in the mouth. Symptoms are typically worse after eating or lying down. Patients with typical GERD should undergo upper endoscopy if they have concerning symptoms, including dysphagia, odynophagia, vomiting, weight loss, gastrointestinal bleeding, or melena. They should also undergo upper endoscopy if they are men over the age of 50 with chronic symptoms (>5 years) and cancer risk factors, such as a history of tobacco use or a family history of cancer.

Young et al. review the evidence regarding the treatment of GERD. They discuss how patients with concerning symptoms or those who are failing symptomatic treatment should undergo upper endoscopy. They recommend treatment with a proton pump inhibitor in patients without alarm symptoms.

Incorrect Answers:
Answer A: A barium swallow would be indicated in a patient who presented with symptoms of esophageal dysphagia. Possible etiologies would include Zenker diverticulum or achalasia. This patient denied any difficulty swallowing or feeling of food being stuck in the throat.

Answer B: Colonoscopy could be considered in this patient if his upper endoscopy is unrevealing, as weight loss and melena could be explained by colorectal cancer. In light of this patient’s GERD, upper endoscopy should be performed first.

Answer C: Helicobacter pylori testing can be useful in the workup of gastric and duodenal ulcers but is not usually performed in the evaluation of GERD. Weight loss and melena raise concerns for carcinoma. Treatment of patients with H. pylori includes a proton pump inhibitor, clarithromycin, and metronidazole.

Answer D: A trial of lansoprazole would not be appropriate for this patient presenting with several worrisome symptoms including melena and weight loss. If the patient had presented with typical GERD without these symptoms, a trial of a PPI would be indicated. Cancer should be ruled out first prior to symptomatic treatment.

Bullet Summary:
Patients with gastroesophageal reflux disease who present with alarm symptoms of weight loss, dysphagia, odynophagia, vomiting, gastrointestinal bleeding, or melena should be evaluated with upper endoscopy.


Question: A 10-year-old girl is admitted to the medical floor for a respiratory infection. The patient lives in a foster home and has been admitted many times. Since birth, the patient has had repeated episodes of pain/pressure over her frontal sinuses and a chronic cough that produces mucus. She was recently treated with amoxicillin for an infection. The patient is in the 25th percentile for height and weight which has been constant since birth. Her guardians state that the patient has normal bowel movements and has been gaining weight appropriately. The patient has a history of tricuspid stenosis. She also recently had magnetic resonance imaging (MRI) of her chest which demonstrated dilation of her airways. Her temperature is 99.5°F (37.5°C), blood pressure is 90/58 mmHg, pulse is 120/min, respirations are 18/min, and oxygen saturation is 94% on room air. Physical exam is notable for bruises along the patient's shins which the guardians state are from playing soccer. The rest of the exam is deferred because the patient starts crying. Which of the following findings is associated with this patient's most likely underlying diagnosis?

Diastolic murmur best heard along the right lower sternal border

Answer: Diastolic murmur best heard along the right lower sternal border

Explanation:
This patient is presenting with recurrent sinus infections suggestive of Kartagener syndrome. Dextrocardia is a common feature in this pathology, which results in right-sided heart sounds or a diastolic murmur best heard along the right lower sternal border for this patient's tricuspid stenosis.

Kartagener syndrome (primary ciliary dyskinesia) occurs secondary to a genetic defect in a patient's cilia. This results in a clinical picture of recurrent sinusitis, recurrent upper respiratory infections, bronchiectasis, and situs inversus (all major organs are a mirror image of where they should be). A physical exam will reveal right-sided heart sounds and a chest radiograph will demonstrate dextrocardia. Treatment is with respiratory support, assistance with mucociliary clearance, and treatment of infections.

Leigh et al. review the evidence regarding the manifestations of Kartagener syndrome. They discuss how about 50% of patients have situs inversus. They recommend respiratory support for these patients given the overlap with other mucociliary clearance disorders such as cystic fibrosis.

Incorrect Answers:
Answer B: Hypocalcemia would be seen in DiGeorge syndrome which presents with CATCH-22 (Cleft palate/lip, Abnormal facies, Thymic aplasia, Cardiac defects, Hypocalcemia, and chromosome 22 deletion). Treatment is with calcium repletion, surgical treatment of cardiac defects, and treatment of infections.

Answer C: Increased chloride in the patient's sweat describes cystic fibrosis which would present with weight loss, failure to thrive, and fatty/foul-smelling stools. Treatment is with respiratory support, assistance with mucociliary clearance, and treatment of infections.

Answer D: Repeat sinus infections secondary to seasonal allergies describe sinusitis, which may be present in this patient but does not explain the entire clinical picture. Treatment is with antihistamines.

Answer E: Social withdrawal and avoidance of eye contact describe child abuse which seems unlikely in this case given the constellation of symptoms that suggest Kartagener syndrome.

Bullet Summary:
Kartagener syndrome presents with recurrent sinusitis, bronchiectasis, and situs inversus.


Question:
A 4-day-old boy presents to the pediatrician with his mother for his 1st well visit. The patient was born at 36 weeks gestation to a 26-year-old primigravid mother via cesarean section for cervical incompetence. The patient required no resuscitation at birth and both mother and child were discharged from the hospital at 2 days of life. The patient has been exclusively breastfed since birth, and his mother reports that he feeds for 20-30 minutes every 2 hours. The patient urinates 7 times per day and has begun passing 2-3 stools per day that his mother describes as “grainy” and the color of “mustard.” His birth weight was 3670 g (8 lb 1 oz), and his current weight is 3487 (7 lb 11 oz). His temperature is 97.1°F (36.2°C), blood pressure is 57/42 mmHg, pulse is 140/min, and respirations are 38/min. On physical exam, the patient’s anterior fontanelle is soft and flat, and his eyes are moderately icteric. His abdomen is soft and non-distended. The patient has the physical exam finding seen in Figure A. His diaper can be seen in Figure B. Laboratory studies reveal the following:

Total bilirubin: 13 mg/dL
Conjugated bilirubin: 0.6 mg/dL

Which of the following is the most appropriate next step in management?

Order spot uric acid to creatinine ratio

Recommend increasing frequency of breastfeeding

Answer: Continue current breastfeeding regimen

Explanation:
This patient presents at day 4 of life with weight loss of 5% of his birth weight, uric acid crystals in his diaper, desquamation of the palms and soles, and unconjugated hyperbilirubinemia, which are normal findings in a newborn. The most appropriate next step in management is continuing his current breastfeeding regimen.

Healthy newborns may lose up to 7% of their birth weight in the first 5 days of life and exhibit dry, peeling skin on the palms and soles as the skin adapts to a drier environment outside the womb. Uric acid crystals that look like “brick dust” are also a normal finding in the diaper during the 1st week of life, as uric acid excretion is highest at birth. All newborns should be evaluated for signs of dehydration, including sunken fontanelles, dry mucous membranes, low urine output, excessive weight loss, and tachycardia. If these findings are not present, continued breastfeeding should be encouraged.

Westerfield et al. review the evidence regarding the benefits of breastfeeding. They discuss how breastfeeding is associated with decreased risk of atopic dermatitis and gastroenteritis. They recommend ensuring proper breastfeeding techniques.

Figure A demonstrates flaking and peeling of the soles (red circles), which is a normal finding in the 1st week of life.

Figure B demonstrates uric acid crystals (“brick dust”) in the diaper (red circle), which is another normal finding that is caused by high uric acid excretion in the 1st few days of life.

Incorrect Answers:
Answer A: Administering intravenous hydration would be appropriate for a severely dehydrated neonate who cannot tolerate hydration orally. This patient is not exhibiting signs of dehydration.

Answer C: Ordering a serum uric acid concentration may be part of an evaluation for Lesch-Nyhan syndrome, an X-linked recessive disorder of purine metabolism caused by deficiency of the enzyme hypoxanthine-guanine phosphoribosyltransferase (HGPRT) that causes hyperuricemia and hyperuricosuria. The uric acid crystals found in this patient’s diapers are a normal finding in the 1st week of life. Treatment is supportive including allopurinol for gout.

Answer D: Ordering a spot uric acid to creatinine ratio would be an appropriate first step in evaluation for Lesch-Nyhan syndrome, but the uric acid crystals in this patient’s diaper are not concerning for Lesch-Nyhan syndrome. Treatment is supportive as well as with allopurinol for gout.

Answer E: Recommending increasing the frequency of breastfeeding would be appropriate for a dehydrated infant with excessive weight loss, but this patient’s weight loss is within the expected limits for the 4th day of life.

Bullet Summary:
Healthy newborns may present with desquamation of the skin and uric acid crystals in the diaper and continued breastfeeding should be encouraged if no signs of dehydration are present.


Question: A 32-year-old G1P0 presents to the antenatal testing unit at 32 weeks of gestation for a non-stress test (NST). Yesterday she had several episodes of diarrhea and vomited once after attending a company picnic 2 days ago. She took loperamide with symptomatic relief. She is worried that she is dehydrated but otherwise feels well and has recovered from her gastrointestinal illness. The patient was diagnosed with gestational diabetes after routine screening in the 2nd trimester and has been started on insulin after unsuccessful attempts at lifestyle management. She also has migraines and gastroesophageal reflux disorder. The patient has a 15-pack-year smoking history but quit smoking in her 1st month of pregnancy. She denies alcohol or drug use. Her temperature is 98.5°F (36.9°C), blood pressure is 122/82 mmHg, pulse is 84/min, and respirations are 14/min. A representative portion of the NST is shown in Figure A. Which of the following is the most likely explanation for this patient’s non-stress test (NST) results?

Answer: Fetal sleep cycle

Explanation:
This patient presents with a nonreactive NST on routine testing. The most common explanation for a nonreactive NST is the fetal sleep cycle.

Patients with gestational diabetes are at increased risk of fetal demise and other perinatal complications. They require closer monitoring during the 3rd trimester of pregnancy. The NST, which lasts 20 minutes, is the most common method of doing so. After 32 weeks, a reactive (i.e. “normal”) NST requires at least 2 episodes of 15-beat-per-minute accelerations lasting for at least 15 seconds. An NST with no accelerations is considered nonreactive. A common cause of a nonreactive NST is the fetal sleep cycle and it is reasonable to continue the test for an additional 20 minutes to increase the chance of monitoring the fetus while awake. Otherwise, a nonreactive NST should prompt vibroacoustic stimulation or further testing such as a biophysical profile (BPP).

Umana and Siccardi review the evidence regarding the use of the NST during pregnancy. They discuss how the test is a measurement of fetal cardiovascular function at the time of the test. They recommend monitoring the baseline fetal heart rate and variability as well as the presence of accelerations and decelerations when interpreting test results.

Figure/Illustration A shows a representative portion of a NST where the fetal heart rate remains within a narrow band without accelerations (red circle). This pattern is characteristically seen in a nonreactive NST that can be due to the fetal sleep cycle.

Incorrect Answers:
Answer B: Maternal dehydration generally should not affect the reactivity of an NST. Although severe dehydration may reduce amniotic fluid volume and therefore increase the baseline fetal pulse, it is unlikely to change the accelerations or variability in an NST. Though this patient had diarrhea the day before, her pulse is not elevated and any dehydration is probably not clinically significant.

Answer C: Maternal medication use can cause nonreactivity on an NST if drugs such as morphine or other sedatives are taken. Although this patient did take loperamide (an opioid), it is unlikely that this has a sedative effect on the fetus as it acts selectively on the mu-opioid receptors in the large intestine and does not cross the blood-brain barrier.

Answer D: Maternal smoking in close proximity to an NST has been linked to nonreactivity, but this patient has not smoked in several months. Mothers who smoke are counseled to avoid smoking on the day of their NST to avoid the effects of nicotine on their test results.

Answer E: A normal result is known as a reactive NST and would present with accelerations and no concerning or late decelerations. This is not a reactive NST due to the lack of appropriate accelerations.

Bullet Summary:
The most common cause of a non-reactive non-stress test is the fetal sleep cycle.


Question: A 25-year-old man presents to his primary care physician with a chief complaint of "failing health." He states that he typically can converse with animals via telepathy but is having trouble right now due to the weather. He has begun taking an assortment of Peruvian herbs to little avail. Otherwise, he is not currently taking any medications. The patient lives alone and works in a health food store. He states that his symptoms have persisted for the past 8 months. When obtaining the patient's medical history, there are several times he attempts to telepathically connect with the animals in the vicinity. His temperature is 98.6°F (37°C), blood pressure is 115/71 mmHg, pulse is 72/min, and respirations are 12/min. On physical exam, you note a healthy young man who is dressed in an all-burlap ensemble. Which of the following is the most likely diagnosis?

Answer: Schizotypal personality disorder

Explanation:
This patient has several odd and eccentric beliefs without frankly psychotic features and he is able to function in society. This suggests a diagnosis of schizotypal personality disorder.

Schizotypal personality disorder presents with eccentric behavior, magical thinking, odd beliefs, and perceptual disturbances. These patients may seem to have symptoms of schizophrenia; however, they do not respond to internal stimuli and do not experience visual or auditory hallucinations. They are able to function in society and care for themselves. Patients with schizotypal personality disorder typically struggle in maintaining close relationships or making friends. Patients are typically not distressed about their thought patterns but can undergo treatment with psychotherapy if they seek to change their behaviors.

Sher reviews the evidence regarding the treatment of patients with schizotypal personality disorder. He discusses how this disorder often goes undiagnosed and is difficult to treat. He recommends providing suicide prevention measures as this disease is associated with suicidal ideation.

Incorrect Answers:
Answer A: Brief psychotic disorder presents with either visual or auditory hallucinations with symptoms that have lasted for less than 1 month. Patients have frankly psychotic features and should be closely monitored for the development of schizophrenia.

Answer B: Schizoid personality disorder presents with social isolation. These patients are alone but do not desire social contact and are content in their isolation. A typical example is an individual who works in a solitary job on the graveyard shift. Patients do not have strange or magical beliefs.

Answer C: Schizophrenia presents with either visual or auditory hallucinations with symptoms that have lasted for 6 months or longer. These patients typically have trouble caring for themselves and struggle to function in society. Though this patient is attempting to connect/communicate with animals, this likely represents an odd belief rather than responding to internal stimuli. Schizophrenia should be treated with antipsychotic medications.

Answer D: Schizophreniform disorder presents with either visual or auditory hallucinations with symptoms that have lasted for 1-6 months. Patients have symptoms with frankly psychotic features and should be treated with antipsychotic medications.

Bullet Summary:
Schizotypal personality disorder presents with eccentric behavior, magical thoughts, and odd beliefs but patients are able to function within society.


Question: A 55-year-old man presents to the emergency department with chest pain and shortness of breath. He has a medical history of hypertension, diabetes, and obesity. His temperature is 98.6°F (37.0°C), blood pressure is 177/118 mmHg, pulse is 127/min, respirations are 11/min, and oxygen saturation is 98% on room air. An ECG is performed and notable for ST elevation in leads II, III, and aVF. The patient is treated appropriately and transferred to the medical floor. On the 2nd day of his hospitalization, the patient has abdominal pain. His serum lipase is 272 U/L and his creatinine is 1.6 mg/dL. A physical exam is notable for the finding in Figure A. He is requesting pain medication for his abdominal pain. Which of the following is the most likely underlying diagnosis?

Answer: Cholesterol embolism

Explanation:
This patient is presenting with abdominal pain and livedo reticularis after a catheterization procedure. These symptoms are suggestive of a cholesterol embolism.

A cholesterol embolism typically presents after any vascular procedure due to a dislodged cholesterol emboli. Symptoms include livedo reticularis, gastrointestinal problems such as mesenteric ischemia or pancreatitis, and acute kidney injury. Patients who have undergone cardiac catheterization should be monitored for the development of this complication. Treatment is centered around treating the current complications, often using supportive therapy as they self-resolve. In addition, patients should be treated carefully to prevent recurrent embolism.

Maningding and Kermani review the evidence regarding the presentation of vasculitis mimics. They discuss how cholesterol embolism can cause diverse systemic symptoms and livedo reticularis. They recommend carefully considering the history of each patient.

Figure/Illustration A is a clinical photograph demonstrating a netlike reticular bluish discoloration of the skin (red circle). These findings are consistent with livedo reticularis.

Incorrect Answers:
Answer B: Heart failure and reinfarction could present with renal failure but would likely present with other symptoms of heart failure as well (pulmonary crackles, edema, and jugular venous distension). Treatment of a repeat infarct involves catheterization and fluid overload involves volume optimization.

Answer C: Medication side effects could explain this patient's livedo reticularis, but the drugs that may cause this (certain antivirals and amantadine) would not have been given to this patient. These medications also typically do not cause abdominal pain.

Answer D: Pancreatitis presents with abdominal pain and an elevated lipase; however, it is not the underlying pathology for this patient's presentation but rather is a complication of the cholesterol embolism. Treatment of pancreatitis is with gastrointestinal rest and fluid support.

Answer E: Renal failure is another complication in this patient secondary to the cholesterol embolism as revealed by the elevated creatinine, but is not the underlying pathology. Treatment is with renal replacement therapy if renal function does not return promptly.

Bullet Summary:
Cholesterol embolism presents after a vascular procedure with livedo reticularis, gastrointestinal complications, and acute kidney injury.


Question: A 25-year-old man is brought to the emergency department by paramedics for altered mental status. He was found lying down at a bus stop unresponsive. On arrival, the patient has slurred speech and is somnolent. Further is unable to be elicited. His temperature is 98.0°F (36.7°C), blood pressure is 130/80 mmHg, pulse is 80/min, and respirations are 12/min with a saturation of 97% on room air. Physical exam reveals a sleeping man with miotic pupils. The patient is easily arousable to voice and sternal rub but falls asleep rapidly. He has decreased bowel sounds. He is able to state his name and knows that he is at the hospital and has an otherwise normal neurologic exam. Which of the following is the most appropriate management?

Answer: Observation

Explanation:
This patient's presentation with altered mental status, pinpoint pupils, and decreased bowel sounds is most consistent with an opioid overdose. Given his stable respiratory status and oxygen saturation without notable bradypnea, observation alone until the patient is clinically sober is the most appropriate management.

Opioids are commonly used to treat painful conditions but have the potential to become drugs of abuse. Opioid overdose presents with bradypnea, somnolence, decreased bowel sounds, and pinpoint pupils. Any patient who is not protecting their airway, failing to oxygenate, or failing to ventilate should immediately be given naloxone which rapidly reverses the effect of opioids. However, this precipitates withdrawal which is unpleasant for patients and leads to nausea, vomiting, agitation, and diaphoresis among other findings. For this reason, patients who have overdosed on opioids and are stable can be observed until clinically sober.

Dietze et al. studied the effect of intranasal versus intramuscular naloxone for opioid overdose in a randomized control trial. The authors found that patients who received intranasal naloxone needed a second dose of naloxone more frequently compared to patients who received intramuscular naloxone. The authors recommend further study of optimal dosing and concentration of intranasal naloxone to respond to opioid overdoses outside of the hospital.

Incorrect Answers:
Answer A: Atropine is an appropriate treatment for a cholinergic toxidrome. This would manifest with bronchorrhea, bronchospasm, bradycardia, urinary incontinence, diarrhea, and drooling. Atropine should be administered until respiratory symptoms improve; large doses may be required.

Answer B: Disulfiram inhibits the enzyme acetaldehyde dehydrogenase causing severe nausea, vomiting, and a very ill feeling when a patient drinks alcohol from the accumulation of byproducts. This drug is a second-line agent used to reduce drinking in chronic alcohol use disorder but has no indication in managing acute alcohol intoxication as it is a preventive medication.

Answer C: Flumazenil is the reversal agent for benzodiazepines. Its use has fallen out of favor as it can precipitate seizures in chronic benzodiazepine users. Any patient with a suspected benzodiazepine overdose who is protecting their airway should be observed until clinically sober as there is no need to rapidly reverse them and possibly cause seizures.

Answer D: Naloxone is the antidote of choice in opioid overdose in patients who are not adequately oxygenating, ventilating, or protecting their airway. It is not indicated in opioid overdose in a clinically stable patient as the patient can merely be observed without the unpleasant side effects of immediate withdrawal from naloxone (including vomiting which in some cases could lead to aspiration). This patient is oxygenating well, protecting his airway, and does not have profound bradypnea.

Bullet Summary:
Opioid overdose presents with somnolence, pinpoint pupils, decreased bowel sounds, and bradypnea; stable patients who are adequately breathing and protecting their airway require only observation until clinically sober.


Question: A 32-year-old man presents to the emergency department with pain upon defecation. His symptoms started a few weeks ago but have been worsening. Sometimes he notes blood on the toilet paper. He has to strain to have bowel movements and has trouble defecating secondary to pain. He is generally healthy and does not smoke. The patient is a software engineer and enjoys hiking, going to nightclubs, and dancing. His temperature is 98.1°F (36.7°C), blood pressure is 112/83 mmHg, pulse is 83/min, respirations are 13/min, and oxygen saturation is 98% on room air. Physical exam reveals a small, superficial fissure that is lateral to the anus and lateral to the midline. Which of the following is the most appropriate management for this patient?

Testing for HIV, fecal occult blood, and sexually transmitted diseases

Answer: Testing for HIV, fecal occult blood, and sexually transmitted diseases

Explanation:
This patient is presenting with pain upon defecation, constipation, and a fissure lateral to the midline which is suggestive of an anal fissure. Anal fissures lateral to the midline are associated with inflammatory and infectious etiologies; thus, further workup (testing for HIV, fecal occult blood testing, and sexually transmitted disease testing) is needed rather than merely symptomatic treatment.

Anal fissures present with exquisite pain upon defecation which may lead to fecal retention and constipation. Commonly, anal fissures are caused by constipation, local trauma (such as anal intercourse), or a tight anal sphincter. Anal fissures that occur secondary to trauma are usually midline. On the other hand, lateral anal fissures are a harbinger of more serious alternative diagnoses and require further workup. Lateral anal fissures can be caused by infections (HIV being one of the most concerning as well as syphilis or tuberculosis), Crohn disease, granulomatous disease, malignancy, as well as foreign bodies. For this reason, lateral anal fissures should not only be treated symptomatically but require testing for sexually transmitted diseases, inflammatory conditions, and malignancy to determine the underlying etiology based on the patient’s risk factors and associated symptoms.

Steele and Madoff review anal fissures. They note that while both operative and non-operative interventions may be indicated in the management of an anal fissure after alternative diagnoses have been ruled out, advances in medical management may spare patients sphincter-dividing surgery. They recommend considering all modalities.

Incorrect Answers:
Answer A: CT scan of the abdomen and pelvis followed by an MRI may be the most appropriate testing if a perirectal abscess is suspected. These abscesses can track very deep. For this reason, further imaging and drainage in the operating room followed by antibiotics are indicated rather than a simple bedside incision and drainage. Imaging may be indicated in this patient after medical workup fails to elucidate an etiology.

Answer B: Incision, drainage, ciprofloxacin, and metronidazole may be indicated for a perianal abscess (note, this is not a perirectal abscess), which presents with a tender, fluctuant mass right next to the anus. The diagnosis can be made clinically or supported by an ultrasound.

Answer C: Surgical excision may be performed in the management of a perianal fistula, which presents with a draining tract next to the anus that releases purulence or fecal contents causing staining of the patient’s underwear and irritation of the skin. The diagnosis is made with an exam and a CT, MRI, or fistulogram followed by a fistulotomy.

Answer E: Topical lidocaine, sitz baths, and fiber supplements are the appropriate management of an anal fissure that is midline and secondary to a clear cause such as trauma or constipation. It would be inappropriate to only treat this patient symptomatically with a lateral anal fissure as this is a sign of a more serious diagnosis.

Bullet Summary:
Anal fissures that are lateral to the midline require workup for sexually transmitted infections, cancer, and autoimmune disease.