Question 1

A 34-year-old man comes to the emergency department due to 3 weeks of nonproductive cough, increasing shortness of breath, subjective fevers, night sweats, and intermittent right-sided, sharp chest pain.  Two weeks ago, the patient was diagnosed with community-acquired pneumonia at an urgent care clinic and received a week of oral antibiotics without symptomatic improvement.  He has no other medical problems and takes no medications.  The patient has a history of injection drug use and was recently incarcerated.  Temperature is 37.7 C (99.8 F), blood pressure is 120/70 mm Hg, and pulse is 88/min.  Chest examination reveals decreased breath sounds and dullness to percussion in the right lower chest.  Heart sounds are normal and without murmurs.  The abdomen is soft and non-tender with no hepatosplenomegaly.  He has no skin rash or enlarged lymph nodes.  Chest imaging reveals a right lower lobe pulmonary infiltrate and moderate-sized pleural effusion.  A thoracentesis is performed; the pleural fluid is lymphocyte predominant and exudative with an elevated adenosine deaminase level.  No organisms are seen on smear.  Rapid HIV testing is positive.  Which of the following is the best next step in management of this patient's pleural effusion?

Accepted Answer

Explanation: This patient with newly diagnosed HIV and recent incarceration has pleural effusion findings that suggest a tuberculous pleural effusion. HIV dramatically increases the risk for acquiring Mycobacterium tuberculosis and reactivating latent disease. Patients with higher CD4 counts who develop active pulmonary tuberculosis (TB) typically manifest apical, cavitary disease. However, those with advanced HIV usually cannot mount sufficient cell-mediated defenses to create cavitations and often present with lobar, pleural, or disseminated infection. Tuberculous effusions usually present with fever, cough, pleurisy, and weight loss. Thoracentesis typically reveals a lymphocyte-predominant, exudative effusion. Although malignancy may present with similar findings, an elevated adenosine deaminase level strongly suggests TB. As tuberculous pleural effusions are caused by a hypersensitivity reaction to M tuberculosis or its antigens, pleural fluid smear is usually aseptic (unlike tuberculous empyemas) and pleural biopsy is often required for diagnosis. (Choice A) This patient requires a definitive diagnosis for his pulmonary infection prior to the consideration of antiretroviral therapy (ART). ART is often delayed for 1-2 weeks after initiating tuberculosis treatment to reduce the risk of immune reconstitution inflammatory syndrome. (Choice B) Pneumocystis pneumonia is common in patients with AIDS and typically causes indolent fever, dyspnea, dry cough, and bilateral, interstitial infiltrates. Lobar infiltrate and pleural effusion are rare. In addition, Pneumocystis pneumonia is initially evaluated with induced sputum samples; bronchoalveolar lavage is the second-line diagnostic test. (Choice C) Most respiratory pathogens that result in a lobar infiltrate and parapneumonic effusion will cause acute (not subacute) symptoms and neutrophil-predominant (not lymphocyte-predominant) pleural fluid. This patient had no improvement with antibiotic therapy for community-acquired pneumonia and likely has TB. (Choice E) Histoplasmosis is an opportunistic infection in patients with HIV and usually presents as a febrile, wasting illness marked by fever, fatigue, weight loss, vomiting, and dyspnea. Chest radiograph is typically normal or reveals diffuse interstitial infiltrate; focal infiltrate and pleural effusion are rare. Educational objective: Patients with HIV are at higher risk for active tuberculosis. Cavitary, apical lung disease is common at higher CD4 counts, but patients with advanced HIV are at greater risk for lobar, pleural, or disseminated disease. Tuberculosis pleural effusions are typically lymphocytic and exudative with an elevated adenosine deaminase level. Smears are often negative for acid-fast bacilli; diagnosis usually requires pleural biopsy with histopathologic demonstration of pleural granulomas.

Question 2

A 6-year-old boy is brought to the office for the first time for a well-child checkup.  The family recently moved to the area, and the boy has been adjusting well and making friends.  He started first grade a month ago and soccer last week.  The patient is a picky eater and his meals consist of fruit, pasta, crackers, and milk.  When asked about his sleep pattern, his mother says, "He sleeps straight through wetting the bed at least twice a week.  We tried to potty train him when he was 3 years old, but he's dry only during the day.  Our last doctor recommended a few behavioral changes.  We have tried avoiding fluids before bedtime and other changes, but nothing seems to help."  The patient has no dysuria or constipation.  He has seasonal allergies for which he takes cetirizine.  He is allergic to shellfish and has an epinephrine injector.  Immunizations are up to date.  Growth is along the 30th percentile for both height and weight.  Blood pressure is 96/62 mm Hg.  The abdomen is soft, nontender, and nondistended.  External genitalia are Tanner stage I with a circumcised penis, normal urethral meatus, and descended testicles bilaterally.  The skin is clear with no rashes.  Which of the following is the best next step in management of this patient?

Accepted Answer

Explanation: 11ec2b69_c091_be6b_8f63_154ddb3d8668_MD0005_00 Enuresis is defined as urinary incontinence at age >5 and is most commonly due to primary nocturnal enuresis, the inability to have ever achieved nighttime dryness. Nocturnal enuresis, which is more common in boys, affects 15% of 5-year-olds and has a declining prevalence to 1% in adolescence. Although secondary causes are unlikely in a patient who has never achieved nighttime dryness, a urinalysis is indicated to exclude more urgent diagnoses. For example, glucosuria is suggestive of diabetes mellitus, which can present with polyuria and polydipsia. Diabetes insipidus can present with enuresis and a low specific gravity on first morning void. Finally, occult infection can present with enuresis in addition to leukocytes and nitrites on urinalysis. A normal urinalysis is reassuring that the diagnosis is likely primary nocturnal enuresis and spontaneous resolution is expected. For motivated families, such as this family, modification of evening behavior, such as limiting fluid intake and voiding before bedtime, is initial management. (Choices A and C) A renal and bladder ultrasound is indicated for children with nocturnal enuresis who have additional urinary symptoms, such as daytime incontinence or weak urinary stream. Evaluation of renal function with a serum creatinine level would be indicated in patients with concomitant signs of renal disease (eg, hypertension). Imaging and laboratory evaluation are not warranted in healthy patients with isolated, primary nocturnal enuresis. (Choice B) An elevated fingerstick glucose level could be suggestive of diabetes mellitus, a potential cause of enuresis. A urinalysis, however, can screen for additional secondary causes of enuresis (eg, diabetes insipidus) as well and is noninvasive. (Choice E) A urine culture is appropriate if screening urinalysis is suggestive of infection (eg, leukocytes, nitrites) or history includes symptoms of dysuria or hematuria. This patient has no other symptoms and does not warrant a urine culture. Educational objective: Primary nocturnal enuresis is the lack of nighttime dryness in children age >5 and resolves spontaneously over time. A screening urinalysis is recommended to exclude underlying etiologies such as diabetes mellitus or insipidus. References: Evaluation of and treatment for monosymptomatic enuresis: a standardization document from the International Children's Continence Society. (http://www.ncbi.nlm.nih.gov/pubmed/20006865)

Question 3

A 6-year-old boy is brought to the office for chronic bedwetting.  He was fully toilet trained for daytime by age 4 but has never consistently stayed dry overnight.  In the past 6 months, his parents have tried several behavioral modifications, with fluid intake restricted for 2 hours prior to bedtime and the patient voiding prior to going to sleep.  His parents also implemented a reward system, but he still wets the bed frequently.  The patient says, "I feel really embarrassed.  I want to go to a sleep-away camp next year but my parents won't let me."  The boy has regular soft bowel movements without stooling accidents.  He has no other medical problems and takes no medication.  Vital signs are appropriate for age.  Physical examination and urinalysis are unremarkable.  His mother says, "I'm really tired of washing the sheets every other day.  What else do you suggest?"  Which of the following is the most appropriate advice regarding this patient's condition?

Accepted Answer

Explanation: 11ec2b69_c090_fb1a_8f63_816c00409fd5_MD0005_00 Primary nocturnal enuresis is the inability to achieve nighttime dryness in healthy patients age >5 without additional urinary tract symptoms (eg, dysuria, daytime incontinence). Management of nocturnal enuresis begins with behavior modifications (eg, limiting fluid intake before bedtime) and motivational therapy (eg, reward system). Continued enuresis after institution of these measures for 3-6 months warrants enuresis alarm therapy, a first-line treatment that has the best long-term outcome and a low risk of relapse. An enuresis alarm is activated when a sensor in the patient's underwear or bed pad detects moisture and triggers an auditory or vibratory alarm that wakes the patient, thereby inhibiting further bladder emptying. With consistent use, the alarm conditions the child to wake prior to voiding. Patient adherence and motivation are required as the child is responsible for responding to the alarm. (Choice A) Having the parent periodically wake the child is not recommended as a long-term solution. The child becomes reliant on the parent's intervention to void rather than on physiologic cues (eg, bladder fullness). (Choice B) Desmopressin, an antidiuretic, is an alternate first-line treatment of primary nocturnal enuresis but has a high rate of relapse after discontinuation. Desmopressin is recommended for families seeking a short-term solution (eg, sleep-away camp) or who have failed/refused enuresis alarm therapy. Adverse effects are rare but include hyponatremia if taken with excessive oral fluids. (Choice D) Tricyclic antidepressants (eg, imipramine) are not first-line therapy for enuresis but can be considered for refractory cases. Efficacy results from the anticholinergic effect of urinary retention; tricyclic antidepressants are not used to treat anxiety in patients with enuresis. (Choice E) If motivational therapy results in significant improvement of enuresis, or if the parents/child can tolerate breakthrough episodes, continued motivational therapy is reasonable. This family has instituted changes for 6 months without success and should be offered alarm therapy. Educational objective: If behavioral modifications (eg, limiting evening fluid intake) and motivational therapy for primary nocturnal enuresis are unsuccessful, first-line treatment includes enuresis alarms and desmopressin. Enuresis alarms provide the best long-term outcome (ie, low rate of relapse). References: Evaluation of and treatment for monosymptomatic enuresis: a standardization document from the International Children's Continence Society. (http://www.ncbi.nlm.nih.gov/pubmed/20006865) Advances in the management of primary monosymptomatic nocturnal enuresis in children. (http://www.ncbi.nlm.nih.gov/pubmed/25936863)

Question 4

A 48-year-old man is brought to the emergency department for what his wife describes as "bizarre behavior" for the last two days. His past medical history is significant for cirrhosis secondary to chronic hepatitis C infection. His daily medications are spironolactone, lactulose, and furosemide. He is an ex-heroin user. Examination shows a drowsy but restless patient. His blood pressure is 94/56 mmHg and heart rate is 112/min with a regular rhythm. The abdomen is distended, soft, and non-tender to palpation. Shifting dullness is present. There is no peripheral edema. Laboratory tests show the following: The peritoneal fluid is sampled yielding 12 WBCs/mm³ and an albumin of 1.0 mg/dL. Renal ultrasound shows no evidence of hydronephrosis. Which of the following is the best next step in managing this patient?

Accepted Answer

Explanation: This patient's abnormal LFTs can be attributed to his known cirrhosis. However, his elevated BUN and creatinine likely indicate acute renal failure, though correlation with any prior creatinine values is needed. The most likely diagnosis is hepatorenal syndrome, but it must be remembered that this is a diagnosis of exclusion. In hepatorenal syndrome, the urinary sediment is usually rather benign. An ultrasound should be performed to exclude the presence of urinary obstruction. Spontaneous bacterial peritonitis (SBP) is a frequent precipitant of hepatorenal syndrome and as such paracentesis is indicated if ascites is present. This patient's cell count is far below the 250 cells/mm³ needed for a diagnosis of SBP. Patients with cirrhosis develop decreased peripheral vascular resistance secondary to splanchnic vasodilation, which can cause the decreased renal perfusion of hepatorenal syndrome. Similarly, volume depletion due to over-diuresis can cause renal dysfunction of a pre-renal etiology. The patient's BUN/Cr ratio of 20:1 is compatible with either scenario. A volume challenge would be an appropriate next step to confirm a diagnosis of hepatorenal syndrome in this patient. A failure to respond would be consistent with hepatorenal syndrome. A combination of octreotide and midodrine or norepinephrine alone can be used if this patient's renal failure does not respond to fluids. Albumin should also be continued for at least 2-3 days. (Choice A) Corticosteroids are used for multiple autoimmune causes of acute renal failure, but are not helpful in the management of hepatorenal syndrome. (Choice B) Loop diuretics should not be given at this point because it is still possible that the patient is volume depleted from prior diuretic therapy. (Choice C) A combination of midodrine and octreotide is preferred to dopamine in the treatment of hepatorenal syndrome. (Choice D) Renal biopsy is generally indicated to identify intrinsic renal disease, such as glomerulonephritis, which can be associated with chronic hepatitis C. However, a BUN/Cr ratio of more than 20 typically indicates a pre-renal picture rather than intrinsic renal disease. Educational objective: Hepatorenal syndrome is a common cause of acute renal failure in patients with cirrhosis but should be considered a diagnosis of exclusion. A fluid bolus is needed to confirm that the renal failure is not secondary to intravascular volume depletion. A combination of midodrine and octreotide along with albumin is the treatment of choice after the diagnosis is confirmed. References: Pathogenetic background for treatment of ascites and hepatorenal syndrome. (http://www.ncbi.nlm.nih.gov/pubmed/19669317) Terlipressin and hepatorenal syndrome: what is important for nephrologists and hepatologists. (http://www.ncbi.nlm.nih.gov/pubmed/21049548) Incidence and prognosis of different types of functional renal failure in cirrhotic patients with ascites. (http://www.ncbi.nlm.nih.gov/pubmed/20399905) Systematic review of randomized trials on vasoconstrictor drugs for hepatorenal syndrome. (http://www.ncbi.nlm.nih.gov/pubmed/19885875)

Question 5

A 42-year-old man comes to the emergency department due to 4 days of nausea, skin rash, progressive weakness, and decreased urine output. For the past few months he has also had fatigue, tingling in his hands and feet, and occasional joint pains. The patient has had no fever, chest pain, dysuria, hematuria, or diarrhea. He has no chronic medical problems and takes no medication. The patient does not use tobacco or alcohol but used injection drugs during his early 20s. Temperature is 37.6 C (99.8 F), blood pressure is 150/90 mm Hg, pulse is 92/min, and respirations are 16/min. BMI is 24.8 kg/m². Mucous membranes are dry with no lesions. Cardiopulmonary auscultation is normal. The liver edge is palpable 2 cm below the right costal margin. Bilateral ankle reflexes are absent. He has mild, bilateral, lower-extremity pitting edema and a palpable, nonblanchable, purpuric rash on both legs. There is no joint swelling or erythema. Laboratory results are as follows: Which of the following is most helpful in establishing the cause of this patient's renal dysfunction?

Accepted Answer

Explanation: This patient has renal insufficiency with palpable purpura, elevated rheumatoid factor, and hypocomplementemia, raising suspicion for mixed cryoglobulinemia syndrome. The diagnosis can be confirmed by measuring serum cryoglobulin levels. Mixed cryoglobulinemia syndrome is a vasculitis due to the deposition of immune complexes (polyclonal IgG and IgM rheumatoid factor) within the vascular wall of small- and medium-size vessels. Most cases arise in those with chronic hepatitis C virus (as is likely in this patient with a history of intravenous drug use), but patients with lymphoproliferative disorders, autoimmune disease, and other infections are also at risk. Patients with mixed cryoglobulinemia syndrome most commonly develop a triad of manifestations: Palpable purpura Weakness Arthralgias Other nonspecific symptoms (eg, nausea) and peripheral neuropathy also frequently occur. Laboratory examination typically reveals elevated rheumatoid factor and hypocomplementemia. Approximately 20% of patients develop glomerulonephritis (red cells, red cell casts, proteinuria) with or without renal insufficiency. (Choice A) Testing for antineutrophil cytoplasmic antibodies can help diagnose granulomatosis with polyangiitis and microscopic polyangiitis. These small-vessel vasculitides typically cause palpable purpura, glomerulonephritis, renal insufficiency, and fatigue. However, they are usually associated with normal or elevated (not low) complement levels and respiratory tract symptoms (eg, sinusitis, rhinorrhea). (Choice B) Elevated anti-dsDNA antibodies are often seen in patients with systemic lupus erythematosus (SLE). SLE can cause fatigue, arthralgias, renal insufficiency, glomerulonephritis, and low complements levels, but palpable purpura is uncommon. Patients with SLE are more likely to have malar rash or discoid lesions. malar rash discoid lesions (Choice C) Antiglomerular basement membrane antibodies are seen in Goodpasture disease, which is associated with acute glomerulonephritis. Patients typically have pulmonary symptoms (eg, alveolar hemorrhage, hemoptysis), and systemic symptoms are rarely present. (Choice E) A streptozyme test can evaluate for a streptococcal infection, which can cause poststreptococcal glomerulonephritis due to immune complex deposition. Manifestations include renal insufficiency, nephritis, and low C3 complement levels. However, most patients have normal C4 complement levels and a recent history of streptococcal pharyngitis or skin infection. In addition, palpable purpura is uncommon. Educational objective: Mixed cryoglobulinemia syndrome is typically associated with chronic hepatitis C virus infection and usually manifests with the triad of palpable purpura, fatigue, and arthralgias. Peripheral neuropathy, systemic symptoms, and glomerulonephritis with renal insufficiency are also common. Diagnosis is typically made by measuring serum cryoglobulin levels. References: Therapy for hepatitis C virus-related cryoglobulinemic vasculitis. (http://www.ncbi.nlm.nih.gov/pubmed/24024840)

Question 6

A newborn girl is evaluated in the nursery for respiratory distress.  Approximately 30 minutes after the patient was born, she developed sudden-onset tachypnea and hypoxia for which she is receiving supplemental oxygen by nasal cannula.  The infant was born to a 35-year-old woman at 39 weeks gestation via a scheduled cesarean delivery for breech presentation.  Membranes ruptured at delivery, revealing clear amniotic fluid.  The mother had insulin-controlled gestational diabetes mellitus and tested positive for Group B Streptococcus at 36 weeks gestation.  Apgar scores were 7 and 8 at 1 and 5 minutes, respectively.  Temperature is 36.7 C (98 F).  Examination shows tachypnea, grunting, nasal flaring, and subcostal and intercostal retractions.  Cardiac examination reveals tachycardia without murmurs.  Femoral pulses are 2+.  Chest x-ray reveals a flattened diaphragm, mild cardiomegaly, and a prominent horizontal fissure on the right side.  Which of the following is the most likely outcome of this patient?

Accepted Answer

Explanation: 11ec2b69_c08c_6732_8f63_7bbcee28a670_MD0005_00 This newborn has respiratory distress and imaging findings consistent with transient tachypnea of the newborn (TTN). TTN is a condition caused by retained fetal lung fluid after delivery. Patients born prematurely or by cesarean section are at increased risk, as typical resorptive mechanisms are activated at term and during labor. TTN also occurs more frequently in infants born to mothers with diabetes (as seen in this case); this is due to impaired fluid clearance in the diabetic fetal lung. TTN presents shortly after birth with tachypnea, increased work of breathing (eg, retractions, nasal flaring), and often cyanosis. However, breath sounds are usually clear on examination. Hyperinflation (ie, flattened diaphragm), mild cardiomegaly, prominent vascular markings, fluid in the interlobar fissures, and pleural effusions may be seen on chest x-ray. Treatment for TTN is supportive and includes supplemental oxygen as needed. Symptoms generally resolve spontaneously within 72 hours with no long-term complications. (Choice A) Permanent neurocognitive impairment is a severe complication of birth asphyxia due to meconium aspiration syndrome, which presents at delivery with respiratory distress from meconium-stained amniotic fluid. Meconium aspiration syndrome is unlikely in this case with clear amniotic fluid. (Choice B) Persistent wheezing and steroid dependence can occur in infants with respiratory distress syndrome who subsequently develop chronic lung disease. Respiratory distress syndrome typically affects premature infants due to deficient pulmonary surfactant, and chest x-ray has a classic ground-glass appearance with air bronchograms. (Choice C) Patients with an untreated ventricular septal defect are at risk for progressive pulmonary hypertension and heart failure; however, a holosystolic murmur, not respiratory distress, would be expected on examination. (Choice D) Recurrent lung infections and failure to thrive are characteristic of cystic fibrosis. Meconium ileus can occur in the newborn period, but respiratory symptoms typically develop over time. Educational objective: Transient tachypnea of the newborn is a common complication of cesarean deliveries resulting from retained fetal lung fluid. Chest x-ray findings include hyperinflation, cardiomegaly, and fluid in the interlobar fissures. The symptoms usually resolve spontaneously within 72 hours with no long-term complications. References: Respiratory distress in the newborn. (http://www.ncbi.nlm.nih.gov/pubmed/25274969)

Question 7

A 59-year-old man comes to the office for a routine wellness examination.  The patient's medical history includes chronic bronchitis, hypertension, hypertriglyceridemia, and basal cell carcinoma.  He smokes a pack of cigarettes per day, with a total 40-pack-year history.  The patient typically consumes 1 or 2 cans of beer each night.  Family medical history is remarkable for heart disease and diabetes mellitus.  The patient had a normal screening colonoscopy 5 years ago.  A chest x-ray from a year ago shows changes consistent with chronic bronchitis.
The patient says he enjoys smoking very much and is reluctant to stop because he has smoked since age 19.  He asks about the benefits of smoking cessation.  What is the most appropriate response by the physician?

Accepted Answer

Explanation: Smoking is associated with an accelerated decline in pulmonary function, and smoking cessation slows this decline. It reduces the risk for chronic obstructive pulmonary disease (COPD) and, in patients with COPD, the risk for exacerbations (Choices A and E). Moreover, studies have shown that individuals who have not smoked for at least 15 years have an 80%-90% reduction in lung cancer risk compared to current smokers (Choice C). However, the lung cancer risk remains elevated by 10%-80% in former smokers compared to individuals who have never smoked. This patient with COPD (chronic bronchitis) should be advised that smoking cessation clearly reduces his risk for COPD exacerbations and lung cancer. (Choice D) Smoking cessation appears to be associated with a decrease in all-cause mortality rates at any age, even in long-term heavy smokers. Educational objective: Smoking cessation reduces the risk for lung cancer and worsening chronic obstructive pulmonary disease, even in long-term heavy smokers. References: Benefits of smoking cessation with focus on cardiovascular and respiratory comorbidities. (http://www.ncbi.nlm.nih.gov/pubmed/21689381) The effects of smoking cessation on the risk of chronic obstructive pulmonary disease exacerbations. (http://www.ncbi.nlm.nih.gov/pubmed/19194768)

Question 8

A 79-year-old woman is hospitalized after a fall that resulted in a left femoral neck fracture.  She tripped over her dog while cleaning her home, hit her head on a bookshelf, and landed on her left side.  Prior to this she had been in her usual state of health; her other medical issues include obesity, type 2 diabetes mellitus, hypertension, chronic kidney disease, and hypothyroidism.  The patient lives at home by herself.  She has smoked a pack of cigarettes daily for 38 years.  She drinks alcohol every weekend.  Results of the patient's initial workup in the emergency department demonstrated the left femoral neck fracture, creatinine of 2.0 mg/dL, and a negative noncontrast head CT.  She was admitted to the hospital and the following day underwent surgical repair.  The procedure was uncomplicated.  However, on postoperative day 3 the patient is noted to be uncomfortable and mildly agitated.  She is unable to coherently explain her symptoms.  Current medications include prophylactic subcutaneous heparin, insulin glargine, omeprazole, hydrocodone, and levothyroxine.  Temperature is 37.7 C (99.9 F), blood pressure is 104/68 mm Hg, pulse is 114/min, and respirations are 28/min.  Pulse oximetry is 86% on room air.  Examination shows equal round and reactive pupils.  Lung examination demonstrates decreased breath sounds at the bilateral bases.  Heart rhythm is regular with normal S1 and S2.  The surgical incision shows no surrounding erythema or purulent drainage.  The patient follows commands and moves all extremities except the left leg.  Laboratory results are as follows:
 Troponin I is undetectable.  Chest x-ray shows slight bibasilar atelectasis without focal consolidation, pleural effusion, or pulmonary edema.  ECG shows sinus tachycardia but is otherwise unremarkable.
Ventilation-perfusion scan shows high probability for pulmonary embolism.  The patient is started on intravenous heparin.  The next day, the nurse reports that the patient has a fever.  The patient still has some chest pain but her shortness of breath and mental status are improved.  There is no cough, abdominal pain, nausea, vomiting, diarrhea, dysuria, urinary frequency, or headache.  Temperature is 38.3 C (101 F), blood pressure is 121/73 mm Hg, pulse is 102/min, and respirations are 22/min.  Oxygen saturation is 92% on 2 L of oxygen by nasal cannula.  She does not appear ill.  The lungs are clear to auscultation.  The abdomen is soft and nontender.  Neurologic examination is nonfocal.  The operative site is healing well without erythema or purulence.  The patient's 2 peripheral IV lines have no evidence of infection.  Indwelling urinary catheter is draining clear yellow urine.  Laboratory results are as follows:
 Chest x-ray shows no new abnormalities.  Urinalysis is normal.  Blood cultures are sent.  Which of the following would be the most appropriate next step for this patient?

Accepted Answer

Explanation: In general, any patient with a body temperature ≥38.3 C (101 F) is considered to have fever. Although fever often indicates the presence of infection, there are numerous other causes of fever (eg, rheumatologic disease, malignancy, medications). Acute pulmonary embolism (PE) is estimated to cause fever in approximately 15% of cases, possibly due to tissue necrosis in the setting of pulmonary infarction. This patient's high pretest probability of PE, combined with a high-probability ventilation-perfusion scan, confirms the diagnosis of acute PE, which is the most likely cause of her fever. The improvement in her clinical status (eg, heart rate, blood pressure, respiratory rate) with intravenous heparin, combined with stable blood leukocytes and absence of clinical evidence of infection (eg, consolidation on chest x-ray, incisional purulence, peripheral line erythema, abnormal urinalysis), makes concomitant infection unlikely. Collection of blood cultures is reasonable; however, continued treatment for acute PE without initiation of antibiotics is most appropriate. (Choices B and C) Initiation of antibiotics for community- or hospital-acquired pneumonia is not appropriate in this patient with no evidence of consolidation on chest x-ray and no cough or sputum production. The fever and ongoing supplemental oxygen requirement are explained by acute PE. (Choice D) Clostridium difficile colitis is a potential cause of fever in hospitalized patients; however, the absence of diarrhea, abdominal tenderness, and recent antibiotic use in this patient makes the diagnosis very unlikely. (Choice E) Fever and ongoing mild tachypnea and tachycardia are readily explained by acute PE; therefore, empiric antibiotics are not appropriate in this clinically stable patient with no other evidence of infection. Educational objective: Acute pulmonary embolism is estimated to cause fever in approximately 15% of cases; therefore, fever in these patients is not an indication for antibiotics in the absence of other evidence of infection (eg, consolidation on chest x-ray, incisional purulence, peripheral line erythema, abnormal urinalysis). References: Guidelines for evaluation of new fever in critically ill adult patients: 2008 updated from the American College of Critical Care Medicine and the Infectious Diseases Society of America. (http://www.ncbi.nlm.nih.gov/pubmed/18379262) Fever in acute pulmonary embolism. (http://www.ncbi.nlm.nih.gov/pubmed/10631196)

Question 9

A 54-year-old man comes to the emergency department after an episode of syncope.  While he was watching television 30 minutes ago, he experienced sudden-onset chest pressure followed by a syncopal episode.  He regained consciousness within a minute but continues to have chest "heaviness" and shortness of breath.  Two days ago, the patient returned home from an extended car trip.  He has a history of hypertension, osteoarthritis, and prostate cancer treated with brachytherapy.  He is a former smoker with a 15-pack-year history and does not use alcohol or illicit drugs.  Temperature is 38.3 C (100.9 F), blood pressure is 81/50 mm Hg, pulse is 110/min and regular, respirations are 26/min, and pulse oximetry is 92% on room air.  The lungs are clear to auscultation.  Cardiac examination shows a nondisplaced point of maximal impulse, with no murmurs but an accentuated pulmonic component of S2.  Laboratory results are as follows:
 ECG shows sinus tachycardia with nonspecific ST-segment and T-wave changes.  CT angiography reveals filling defects in the bilateral main pulmonary arteries.  Blood pressure after multiple fluid boluses is 85/60 mm Hg and pulse is 108/min.
The patient develops progressive hypoxemia requiring 100% supplemental oxygen via a nonrebreather mask, but even with treatment his respiratory distress worsens and he becomes progressively confused and lethargic.  Endotracheal intubation is performed and mechanical ventilation is initiated.  Intravenous norepinephrine infusion is started due to persistent hypotension.  Bedside echocardiography reveals right ventricular dilation and hypokinesis, but left ventricular contractility is normal.  Which of the following is the best next step in management of this patient?

Accepted Answer

Explanation: 11ec2b69_c08b_2eb0_8f63_4d67bddd482c_MD0005_00 This patient who has a pulmonary embolism (PE) associated with right ventricular dysfunction and hemodynamic instability requiring vasopressor support should receive immediate thrombolytic therapy. In patients with PE, hemodynamic instability is the most important indication for thrombolysis, which can be administered via either systemic infusion or catheter-directed therapy. Other relative indications for thrombolysis include severe right ventricular dysfunction, large clot burden, and evidence of free, right-sided cardiac thrombus. Contraindications include intracranial neoplasm or prior hemorrhage, cerebrovascular abnormalities, active bleeding, and recent cranial trauma. In patients who cannot undergo thrombolytic therapy, surgical or catheter-directed embolectomy should be considered. (Choice B) Inotropic support (eg, milrinone) may be warranted in patients with acutely decompensated heart failure or right heart failure due to myocardial ischemia, but it would not treat this patient's underlying problem (pulmonary arterial thrombotic obstruction) and is not the next step in management. (Choice C) Although most patients with PE should be started on anticoagulation (eg, heparin), those with hemodynamic instability should have anticoagulation held until after thrombolytic therapy to minimize bleeding risk. (Choice D) Low tidal volume ventilation is important for preventing the risk of barotrauma in acute respiratory distress syndrome, which is due to diffuse inflammatory changes in the lungs and does not typically cause right ventricular dilation and hypokinesis. Patients with hemodynamic instability due to PE require emergent thrombolysis. (Choice E) The most common reasons for the placement of an inferior vena cava filter include the inability to tolerate anticoagulation or breakthrough PE on anticoagulation. Although filters may be placed prophylactically in patients who are unlikely to tolerate another PE, they are not first-line management. Educational objective: Hemodynamic instability is the most important indication for thrombolysis in patients with pulmonary embolism. Other relative indications for thrombolysis include severe right ventricular dysfunction, large clot burden, and evidence of free, right-sided cardiac thrombus. References: Advanced treatment strategies for acute pulmonary embolism, including thrombolysis and embolectomy. (http://www.ncbi.nlm.nih.gov/pubmed/19630826) Developments in the management and treatment of pulmonary embolism. (http://www.ncbi.nlm.nih.gov/pubmed/26324810)

Question 10

A 54-year-old man comes to the emergency department after an episode of syncope.  While he was watching television 30 minutes ago, he experienced sudden-onset chest pressure followed by a syncopal episode.  He regained consciousness within a minute but continues to have chest "heaviness" and shortness of breath.  Two days ago, the patient returned home from an extended car trip.  He has a history of hypertension, osteoarthritis, and prostate cancer treated with brachytherapy.  He is a former smoker with a 15-pack-year history and does not use alcohol or illicit drugs.  Temperature is 38.3 C (100.9 F), blood pressure is 81/50 mm Hg, pulse is 110/min and regular, respirations are 26/min, and pulse oximetry is 92% on room air.  The lungs are clear to auscultation.  Cardiac examination shows a nondisplaced point of maximal impulse, with no murmurs but an accentuated pulmonic component of S2.  Laboratory results are as follows:
 ECG shows sinus tachycardia with nonspecific ST-segment and T-wave changes.  CT angiography reveals filling defects in the bilateral main pulmonary arteries.  Blood pressure after multiple fluid boluses is 85/60 mm Hg and pulse is 108/min.
Which of the following findings in this patient is most predictive of increased 30-day mortality?

Accepted Answer

Explanation: 11ec2b69_c08a_b97d_8f63_9d6bcf8743a1_MD0005_00 This patient with chest pressure, syncope, and pulmonary artery filling defects on CT angiogram has a pulmonary embolism (PE) associated with hemodynamic instability, an important predictor of poor prognosis. Identifying patients at risk for adverse events is particularly important, as management options range from discharge home from the emergency department with anticoagulation to performance of embolectomy. Hemodynamic instability in acute PE is defined as persistent hypotension (systolic blood pressure <90 mm Hg), hypotension requiring vasopressors, or hypotension with evidence of end-organ damage (shock). Hemodynamic instability frequently occurs due to right ventricular dysfunction and is one of the most important predictors of increased short-term mortality. Other clinical predictors include advanced age (>80), altered mental status, history of cancer, tachypnea >30/min, tachycardia >110/min, hypothermia <36 C (96.8 F), and oxygen saturation <90%. Right ventricular dysfunction as seen on echocardiography or CT scan and laboratory abnormalities such as elevated troponin or brain natriuretic peptide levels have also been associated with worse outcomes. (Choices A, C, D, and E) Fever and a loud P2 can both occur with acute PE, and respiratory alkalosis (due to tachypnea) is the typical presentation of acute PE. However, none of these findings is associated with worse prognosis or increased mortality. Hypoxemia is common in acute PE, but levels ≥90% have not been associated with worse outcomes. Educational objective: Hemodynamic instability after pulmonary embolism is frequently due to right ventricular dysfunction and is one of the most important predictors of increased short-term mortality. Other predictors include advanced age, altered mental status, history of cancer, tachypnea, tachycardia, hypothermia, marked hypoxemia, and right ventricular dysfunction. References: The prognostic value of pulmonary embolism severity index in acute pulmonary embolism: a meta-analysis. (http://www.ncbi.nlm.nih.gov/pubmed/23210843) Prognostic models in acute pulmonary embolism: a systematic review and meta-analysis. (http://www.ncbi.nlm.nih.gov/pubmed/27130162)

Question 11

A 24-year-old woman, gravida 1 para 0, at 11 weeks gestation comes to the office for a routine prenatal visit.  The patient is doing well and has no vaginal bleeding or cramping.  Earlier in the pregnancy, she had mild nausea that she managed by eating multiple small meals throughout the day.  The patient has a history of cystitis that occurred prior to pregnancy, but currently has no dysuria or hematuria.  She has no chronic medical conditions or previous surgeries.  She takes a daily prenatal vitamin.  The patient has no known drug allergies and does not use tobacco, alcohol, or illicit drugs.  She runs on a treadmill for 45 minutes, 4 times a week.  Temperature is 36.7 C (98 F), blood pressure is 124/74 mm Hg, and pulse is 78/min.  Fetal heart rate is 140/min by Doppler ultrasound.  Physical examination is otherwise unremarkable.  Laboratory results from her initial prenatal visit are reviewed; a routine clean catch urine culture grew >100,000 colony-forming units/mL of Escherichia coli.  Which of the following is the best next step in management of this patient?

Accepted Answer

Explanation: 11ec2b69_c08e_3bf4_8f63_5f5143366a7e_MD0005_00 Asymptomatic bacteriuria is the presence of >100,000 colony-forming units/mL in a clean catch urine specimen from a patient without symptoms of cystitis (eg, dysuria, hematuria, frequency, urgency). Nonpregnant patients with asymptomatic bacteriuria do not require treatment as it does not reduce the risk of symptomatic infection or its complications (eg, pyelonephritis) in this patient population. In contrast, pregnant patients with asymptomatic bacteriuria are at increased risk for acute pyelonephritis due to the effects of progesterone on the upper urinary tract (eg, smooth muscle dilation, ureteral enlargement, vesicoureteral valve dysfunction). In addition, untreated asymptomatic bacteriuria is associated with fetal complications, including preterm birth, low birth weight, and perinatal mortality. Therefore, pregnant women are screened at the initial prenatal visit via clean catch urine culture and treated as needed with antibiotics to decrease the risk of both maternal and fetal complications (Choice D). Although treatment is guided by culture susceptibility, first-line antibiotics during pregnancy include cephalexin for 3-7 days, amoxicillin-clavulanate for 3-7 days, or fosfomycin as a single dose. Because treatment failure is common, a repeat urine culture is performed a week after completion of the antibiotic regimen to test for cure. (Choice B) Patients with acute pyelonephritis during pregnancy receive a treatment course of antibiotics. Once treatment is completed, they receive daily antibiotic suppression until 6 weeks postpartum to prevent recurrence. During the first trimester, nitrofurantoin is a second-line antibiotic due to potential associations with congenital defects. It is contraindicated at term due to an increased risk of hemolytic anemia in the newborn. (Choice C) Trimethoprim-sulfamethoxazole is a first-line treatment for acute cystitis in nonpregnant women. However, its use in the first trimester has been associated with neural tube defects due to the folate antagonist properties of trimethoprim. Use in the late third trimester is associated with neonatal kernicterus. (Choice E) This patient's bacteriuria is unlikely to clear without antibiotic treatment; therefore, a confirmatory urine culture is not indicated. In addition, delaying treatment to await the results of a second culture places the patient at increased risk of progression to symptomatic cystitis and/or pyelonephritis. Educational objective: Treatment of asymptomatic bacteriuria during pregnancy decreases the risk of maternal (eg, pyelonephritis) and fetal complications (eg, preterm birth, low birth weight, perinatal mortality). First-line antibiotics during pregnancy include cephalexin, amoxicillin-clavulanate, or fosfomycin. References: Duration of treatment for asymptomatic bacteriuria during pregnancy. (http://www.ncbi.nlm.nih.gov/pubmed/22161364) Screening and treating asymptomatic bacteriuria in pregnancy (http://www.ncbi.nlm.nih.gov/pubmed/20139763)

Question 12

A 13-year-old boy comes to the office with his mother because of bed-wetting.  The boy was toilet trained for urine during the day and night by age 3.  Over the past 2 weeks, he has been wetting his bed every night.  His mother has asked him to not drink juice just before bedtime, but he has ignored her.  In the past few days, he also has refused to help with household chores and participate in gym class.  The patient is developmentally appropriate for age and does not take any medication.  Medical history includes oppositional defiant disorder, which is managed with behavioral counseling.  Compared to 6 months ago, his height has increased along the 50th percentile, but his weight has remained stable at 44 kg (97 lb).  Vital signs are normal.  Examination is unremarkable.  Which of the following is the best next step in management of this patient?

Accepted Answer

Explanation: 11ec2b69_c092_339c_8f63_b7fccdd0bf6c_MD0005_00 This patient has secondary nocturnal enuresis, which is defined as new-onset bed-wetting in a child age ≥5 who had previously achieved overnight dryness for a prolonged period (≥6 months). Although primary enuresis (in which nighttime urinary continence has never been established) is a common and generally self-resolving condition in childhood, secondary enuresis in an adolescent should raise suspicion for a psychological stressor (eg, parents' divorce) or an underlying medical condition. Enuresis may be a sign of polyuria and the presenting feature of diabetes mellitus, particularly in a patient with poor weight gain, as in this boy who has grown taller but has not gained weight over the past 6 months. Other findings may be subtle but can include lethargy (eg, refusal to participate in gym class or perform chores) and polydipsia (eg, insistence on drinking juice at bedtime). The first step in evaluation of a child with nocturnal enuresis is urinalysis to exclude medical causes (eg, urinary tract infection); glucosuria supports the diagnosis of diabetes mellitus. Enuresis concerning for diabetes mellitus also warrants checking serum chemistries; elevated blood glucose (ie, ≥200 mg/dL on random testing or ≥126 mg/dL if fasting) suggests the diagnosis. Electrolyte derangements associated with hyperglycemia may also be identified and include hyponatremia and hypokalemia. (Choices B and E) Patients with isolated primary nocturnal enuresis may benefit from enuresis alarm therapy, which conditions the brain to prevent enuresis by waking the patient after bed-wetting. These patients also are often instructed to keep a voiding diary to identify modifiable behavioral habits (eg, evening fluid intake). In contrast, this patient has secondary enuresis with poor weight gain, findings requiring workup for a medical cause. (Choices C and D) In addition to cognitive-behavioral therapy, treatment for oppositional defiant disorder (ODD) can include parent management training (eg, how to provide consistent consequences). A selective serotonin reuptake inhibitor may also be considered for ODD with comorbid anxiety or depression. However, ODD does not explain this patient's enuresis or poor weight gain. His new defiant behaviors (eg, refusing to do chores) may be due to underlying fatigue associated with new-onset diabetes. Educational objective: An underlying medical condition such as diabetes mellitus should be suspected in a child with secondary enuresis (ie, bed-wetting after establishing a prolonged period of nighttime dryness) and poor weight gain. Evaluation includes urinalysis and serum chemistries. References: Primary and secondary enuresis: pathophysiology, diagnosis, and treatment. (http://www.ncbi.nlm.nih.gov/pubmed/28888814)

Question 13

A 17-year-old male presents to the office because he had an episode of cola-colored urine. He appears scared and says that he ran 12 miles two days ago as a part of 'a run for heart disease awareness.' His past medical history is insignificant. He denies any recent upper respiratory or skin infections. He does not smoke or consume alcohol, and says that he has never used any recreational drugs. His father has hypertension and coronary artery disease. His temperature is 37.2 C (98.9 F), blood pressure is 118/76 mmHg and pulse is 78/min. His BMI is 23 kg/m². The physical examination is unremarkable. Urinalysis is positive for blood; there are numerous (100+) RBCs/hpf. Urine sediment did not show any RBC casts. Which of the following is the most appropriate next step in management?

Accepted Answer

Explanation: The differential diagnosis for this patient's cola-colored urine following exercise includes exercise-induced hematuria, myoglobinuria from rhabdomyolysis, and march hemoglobinuria from RBC trauma. All of these entities may result in a positive result for blood on urinalysis, although identifying intact RBCs on microscopy excludes myoglobinuria and hemoglobinuria. The absence of red blood cell casts also makes a glomerular cause of his hematuria less likely. Exercise-induced hematuria is therefore the most likely diagnosis in this patient. Up to 24% of participants in marathons may have exercise induced hematuria. This hematuria may be caused by repetitive up and down movements of the bladder during running. In contact sports, direct trauma to the kidneys or bladder may result in hematuria. Shunting of blood flow towards the muscles and away from the kidneys may also contribute. Even when an appropriate history is present, exercise hematuria should be considered a diagnosis of exclusion and repeat urinalysis should be done in one week to ensure resolution. Further evaluation would then be necessary if hematuria were still present, particularly in patients over the age of 50. (Choice A) Cystoscopy would not be needed unless this patient's hematuria persisted beyond one week. Bladder contusions are frequently seen if cystoscopy is performed, and their presence does not change management. (Choice B) CT has largely replaced intravenous pyelography in the evaluation of hematuria, but neither would be needed at the current time. (Choice C) Renal biopsy is indicated if he were suspected to have glomerulonephritis. (Choice E) Myoglobinuria from rhabdomyolysis would be on the differential diagnosis for this patient, but it is excluded by the visualization of RBCs on urine microscopy. If rhabdomyolysis is suspected, serum CPK would be more helpful than serum myoglobin level. Educational objective: Hematuria frequently occurs with extremely strenuous exercise, and can occur in both contact and non-contact sports. The diagnosis should be considered one of exclusion even with the appropriate history, and follow up urinalysis is needed in 1 week to ensure that the hematuria has resolved. References: Renal alterations during exercise. (http://www.ncbi.nlm.nih.gov/pubmed/18089464) Exercise-induced hematuria. (http://www.ncbi.nlm.nih.gov/pubmed/8594866)

Question 14

A 54-year-old woman comes to the physician with blood in the urine for a week.  It initially occurred once daily, but the frequency increased to twice daily yesterday.  The patient has a history of diabetes, osteoarthritis in her knees, and menopause 5 years ago.  Her medications include daily metformin and ibuprofen as needed.  She has a 30-pack-year smoking history and drinks 1 or 2 beers daily.  Her mother had a history of kidney stones and died of breast cancer.  She lives with her husband, and her last sexual encounter was approximately 10 days ago.  Vital signs are within normal limits.  Examination shows no abnormalities.  Which of the following is the most appropriate next step in management of this patient?

Accepted Answer

Explanation: 11ec2b69_c092_cfdd_8f63_eff1386650e0_MD0005_00 Gross hematuria (ie, macroscopic or visible) may be due to renal (eg, glomerulonephritis, infection), ureteral (eg, nephrolithiasis), bladder (eg, cystitis, malignancy), or urethral (eg, urethritis, prostatitis) etiologies. In the absence of trauma or suspected nephrolithiasis, the first step in evaluating hematuria is obtaining a urinalysis (UA) and urine culture. A UA confirms the presence of hematuria and can differentiate between infectious, glomerular, and extraglomerular causes. Patients with UA findings suggestive of infection and positive urine culture results or symptoms of urinary infection (eg, dysuria, increased urgency, frequency) should receive a course of antibiotics. Patients with UA findings suggestive of glomerular etiologies for hematuria (eg, proteinuria, red cell casts, dysmorphic red cells) require evaluation for renal causes, including possible renal ultrasound, 24-hour urine studies, serological studies, and eventual renal biopsy (Choices B and C). (Choices A and E) If the etiology of hematuria remains unclear, patients should undergo further imaging (CT urography preferred), and those with risk factors (eg, age >35, smoking history, chronic analgesic abuse, pelvic irradiation, chemical exposure) for urologic malignancy in particular should be referred to a urologist for likely cystoscopy. Educational objective: The first step in evaluating hematuria is a urinalysis and urine culture. Urinalysis confirms the presence of hematuria and can differentiate between infectious, glomerular, and extraglomerular causes. References: Assessment of hematuria. (http://www.ncbi.nlm.nih.gov/pubmed/21095418)

Question 15

What is the most appropriate means of correcting this patient's hyponatremia?

Accepted Answer

Explanation: The hyponatremia that arises in SIADH is secondary to the combination of water retention and the loss of sodium and potassium. In chronic SIADH, the loss of sodium is more significant than the amount of water retained. Unless there are neurologic symptoms arising from the hyponatremia, it should be corrected slowly with water restriction (Choice A). Once water restriction is initiated, the plasma sodium concentration will slowly begin to normalize. An ideal rate of increase is 0.5 mEq/h. Patients must be simultaneously monitored for volume depletion as a sodium deficit may become apparent, requiring concomitant administration of salt. Demeclocycline (Choice B) and lithium (Choice E) work to blunt the response of the collecting tubule cells to ADH, ultimately increasing the excretion of water. These drugs are indicated in patients with persistent severe hyponatremia when water restriction, salt intake, or loop diuretics fail to resolve the condition. Although it is potentially nephrotoxic, demeclocycline is typically preferred to lithium because it is more effective and less toxic. Furosemide (Choice C) lowers the urine osmolality and blunts renal response to ADH, thereby increasing water excretion. Since loop diuretics decrease NaCl reabsorption in the loop of Henle, they should be administered concomitantly with hypertonic saline or salt tablets. Hydrochlorothiazide (Choice D) may induce hyponatremia, typically within a few weeks of starting therapy. Thiazides cause the loss of both sodium and water, and when the water is better replaced than the sodium, hyponatremia ensues. Educational Objective: Water restriction (with the possible inclusion of salt administration) is the preferred means of correcting mild to moderate hyponatremia associated with SIADH.

Question 16

A 76-year-old woman is hospitalized due to a fracture of her right proximal femur from an accidental nonsyncopal fall. Medical history is notable for breast cancer treated with a radical mastectomy 10 years ago, hypertension, and hyperlipidemia. She drinks a pint of vodka daily, but does not use tobacco or illicit drugs. The patient is started on thiamine and folic acid, and the next morning she undergoes orthopedic surgery for internal fixation of the right femur. She experiences mild agitation postoperatively, which is managed with as-needed, low-dose benzodiazepines. In addition, she is treated with low-molecular-weight heparin, opiates, and continued vitamin supplementation. On her third postoperative day, the nurse finds her agitated and in significant distress. The patient has an episode of nonbloody vomiting. On initial evaluation, she appears restless and confused but follows commands. Temperature is 36.7 C (98 F), blood pressure is 92/58 mm Hg, pulse is 122/min and regular, and respirations are 31/min. Pulse oximetry is 75% on room air and improves to 82% with supplemental oxygen by non-rebreather mask. Chest auscultation reveals no crackles or wheezes. Cardiac examination demonstrates tachycardia with a regular rhythm and normal S1 and S2. The abdomen is soft. Her pupils are equal and reactive to light, and she is moving all extremities. The patient is successfully intubated and put on mechanical ventilation. Initial settings include fraction of inspired oxygen set to 100% and positive end-expiratory pressure of 5 cm H₂O. Pulse oximetry shows 96%. Her blood pressure drops to 78/42 mm Hg and pulse is 120/min. ECG shows sinus tachycardia and a new right bundle branch block with no ST-segment or T-wave changes. Chest x-ray reveals a normal cardiac silhouette and no infiltrates. Which of the following is most likely to show on emergent bedside echocardiogram?

Accepted Answer

Explanation: This patient's acute respiratory failure is most likely due to an acute massive pulmonary embolism (PE). Although administration of prophylactic low-molecular-weight heparin lowers the risk of PE, it is not completely preventive. Recent femur fracture, orthopedic surgery, and immobility all increase the risk of acute PE, and clinical presentation of hypotension and marked hypoxemia in the absence of pulmonary infiltrates are highly suggestive of the diagnosis. Sinus tachycardia is the most common arrhythmia found on ECG in patients with acute PE. Other consistent ECG findings that occur due to right ventricular (RV) strain include new right bundle branch block, atrial arrhythmias, and Q-waves or ST-segment changes in the inferior leads. In patients who are too hemodynamically unstable to undergo more definitive testing (eg, CT angiogram of the chest), bedside echocardiography is often performed and can strongly support the diagnosis of acute PE. Echocardiographic evidence of RV dysfunction, decreased RV contractility, and presence of RV thrombus are consistent findings. In addition, pulmonary hypertension caused by massive PE often leads to dilation of the tricuspid valve annulus and functional tricuspid valve regurgitation seen on echocardiogram. (Choice A) Massive PE is typically associated with global RV dysfunction. Less commonly, it may cause inferior-posterior wall hypokinesis affecting both the right and left ventricle, but this pattern is more typical of myocardial infarction. The lack of ischemic ECG findings and absence of pulmonary edema in this patient make this finding less likely. (Choice B) A large pericardial effusion would typically reveal cardiomegaly on chest X-ray and low-voltage QRS complexes, rather than right bundle branch block on ECG. (Choice C) Aortic valve insufficiency can occur in acute aortic dissection but is not associated with acute PE. Marked hypoxemia is not typical of acute aortic dissection. (Choice D) Severe, rather than moderate, mitral regurgitation can occur due to papillary muscle rupture in acute myocardial infarction. However, mitral regurgitation is not typically associated with acute PE. Educational objective: Massive pulmonary embolism causes pulmonary hypertension, which can lead to acute right ventricular dysfunction, tricuspid annulus dilation, and functional tricuspid valve regurgitation. Bedside echocardiography can aid in the diagnosis of acute, massive pulmonary embolism. References: Echocardiographic evaluation of pulmonary embolism and its response to therapeutic interventions. (http://www.ncbi.nlm.nih.gov/pubmed/1555480)

Question 17

A 55-year-old man comes to the office for a routine checkup. The patient was diagnosed with type 2 diabetes mellitus 3 years ago, and treatment was initiated with metformin and lifestyle modification. Liraglutide was added to his medical regimen a year ago due to inadequate glycemic control. The patient reports no symptoms other than the occasional "feelings of low blood sugar" when he skips a meal. Blood glucose readings during those episodes have been 60-70 mg/dL. He also takes atorvastatin for hyperlipidemia and low-dose aspirin. The patient smoked a pack of cigarettes daily for 30 years but quit when he was diagnosed with diabetes. He does not use alcohol or recreational drugs. Blood pressure is 128/80 mm Hg, pulse is 76/min, and respirations are 14/min. BMI is 27.5 kg/m². Physical examination shows normal heart and lung sounds and normal pulses in the extremities. There are no lower extremity ulcers or calluses, and vibration and sensory function is intact. Pressure testing with a 10-g monofilament is normal. Laboratory results are as follows: Urinalysis is negative for protein, glucose, cells, or casts, and ECG shows no abnormalities. Which of the following is the most appropriate next step in management of this patient?

Accepted Answer

Explanation: Diabetic kidney disease (DKD) is a common complication in patients with longstanding diabetes. Patients can develop proteinuria and progressive renal dysfunction. Rising serum creatinine occurs late in the disease; therefore, it is critical to assess urinary protein (ie, albumin) excretion as a more sensitive marker for early DKD. Normal albumin excretion is <30 mg/day. Patients are diagnosed as having moderately increased albuminuria (previously known as microalbuminuria) with excretion of 30-300 mg/day and severely increased albuminuria (previously known as overt proteinuria) with excretion >300 mg/day. Ordinary (dipstick) urinalysis is insensitive for early nephropathy and may not be positive until albumin excretion is >300 mg/day. Options for screening include: 24-hour urine albumin: Gold standard test but cumbersome and often incorrectly collected by patients Spot urine albumin: Easy to obtain but accuracy varies with fluid intake and urinary output Urine albumin/creatinine ratio (untimed): Corrects for fluid balance and improves accuracy compared to spot sample and therefore the most preferred and practical test Patients with type 1 diabetes should be screened for early DKD starting 5 years after diagnosis. In contrast, patients with type 2 diabetes often have hyperglycemia (and glomerular injury) for years before diagnosis and should therefore be screened yearly beginning at the time of diagnosis. (Choice A) ACE inhibitors (eg, lisinopril) and angiotensin II receptor blockers are the preferred medications for hypertension in patients with diabetes and for normotensive patients with DKD. However, they are not recommended for normotensive patients without DKD. (Choice C) This patient has good overall glycemic control. Although he has hypoglycemic symptoms when he misses a meal, his glucose at these times is not significantly low. Liraglutide has a low risk of severe hypoglycemia and should be continued. (Choice D) This patient has a small elevation in triglycerides of minimal clinical significance. Niacin can lower triglycerides but is not proven to reduce the risk of cardiac events in patients on statin therapy. (Choice E) This patient is at risk for coronary artery disease but has good glycemic and blood pressure control and is on statin and antiplatelet therapy. No changes in management are necessary regardless of findings on stress testing. Screening asymptomatic patients for coronary disease is not recommended. Educational objective: Patients with diabetes should be screened yearly for diabetic kidney disease with a urine albumin/creatinine ratio. Serum creatinine and dipstick urine protein testing have low sensitivity and are not recommended for screening. References: Diabetic kidney disease: diagnosis, treatment, and prevention. (http://www.ncbi.nlm.nih.gov/pubmed/31194487) Update on diabetic nephropathy: core curriculum 2018. (http://www.ncbi.nlm.nih.gov/pubmed/29398179)

Question 18

A 42-year-old man comes to the emergency department due to 4 days of nausea, skin rash, progressive weakness, and decreased urine output. For the past few months he has also had fatigue, tingling in his hands and feet, and occasional joint pains. The patient has had no fever, chest pain, dysuria, hematuria, or diarrhea. He has no chronic medical problems and takes no medication. The patient does not use tobacco or alcohol but used injection drugs during his early 20s. Temperature is 37.6 C (99.8 F), blood pressure is 150/90 mm Hg, pulse is 92/min, and respirations are 16/min. BMI is 24.8 kg/m². Mucous membranes are dry with no lesions. Cardiopulmonary auscultation is normal. The liver edge is palpable 2 cm below the right costal margin. Bilateral ankle reflexes are absent. He has mild, bilateral, lower-extremity pitting edema and a palpable, nonblanchable, purpuric rash on both legs. There is no joint swelling or erythema. Laboratory results are as follows: The diagnosis is established and the patient's renal function stabilizes with initial therapy. Which of the following is most appropriate for the long-term management of this patient?

Accepted Answer

Explanation: Most cases of mixed cryoglobulinemia syndrome are secondary to an underlying inflammatory condition, which generates the immune complexes that drives the vasculitis. As such, the treatment of mixed cryoglobulinemia syndrome is typically divided into 2 stages: Initial immunosuppressive therapy - stabilizes end-organ damage (eg, glomerulonephritis) using rituximab plus prednisone Treatment of underlying disease - targeted therapy against the condition that triggered the cryoglobulinemia This patient received initial immunosuppressive therapy, and his renal function stabilized. He now requires treatment of the underlying condition that triggered the cryoglobulinemia. The most likely causative factor in this patient with intravenous drug use, hepatomegaly, and elevated aminotransferases is chronic hepatitis C virus. Treatment with antiviral therapy will likely be required. (Choice A) Patients who receive immunosuppressive treatment with rituximab and prednisone require prophylaxis against opportunistic infections such as Pneumocystis pneumonia. However, immunosuppression is typically tapered over 1-3 months; antibiotic prophylaxis would not be necessary in the long-term management of this patient. (Choice C) Mixed cryoglobulinemia syndrome is usually triggered by an underlying disorder such as hepatitis C virus, hepatitis B virus, HIV, malignancy, or rheumatologic disease. All patients require treatment of the underlying disorder to prevent progression; observation would be inappropriate. (Choice D) Transient immunosuppressive therapy is typically required to halt end-organ damage in patients with severe disease. Extended immunosuppressive treatment exposes the patient to unnecessary risks (eg, opportunistic infection) and can worsen the underlying condition (eg, hepatitis C, HIV) that triggered the cryoglobulinemia. (Choice E) Liver-kidney transplantation is considered in patients with decompensated cirrhosis and end-stage renal failure from mixed cryoglobulinemia syndrome. This patient's renal function has stabilized with initial therapy; he now requires treatment of the likely underlying hepatitis C virus infection. Educational objective: Mixed cryoglobulinemia syndrome is typically treated with immunosuppressive therapy (eg, corticosteroids and rituximab) followed by targeted therapy against the underlying condition that triggered the disease. Patients with underlying hepatitis C virus (the most common trigger) should receive antiviral treatment. References: Therapy for hepatitis C virus-related cryoglobulinemic vasculitis. (http://www.ncbi.nlm.nih.gov/pubmed/24024840) Hepatitis C guidance: AASLD-IDSA recommendations for testing, managing, and treating adults infected with hepatitis C virus. (http://www.ncbi.nlm.nih.gov/pubmed/26111063)

Question 19

A 62-year-old woman comes to the office due to fatigue and lethargy over the last 6 months.  She has a history of chronic kidney disease due to long-standing type 2 diabetes mellitus and hypertension.  Temperature is 36.7 C (98 F), blood pressure is 140/90 mm Hg, pulse is 84/min, and respirations are 16/min.  There is conjunctival pallor.  The lung fields are clear, and no murmurs are heard on cardiac examination.  The abdomen is nontender.  Test of the stool for occult blood is negative.  Laboratory results are as follows:  Which of the following is the best next step in management of this patient's anemia?

Accepted Answer

Explanation: Patients with advanced chronic kidney disease (CKD) or end-stage renal disease commonly develop a hypoproliferative, normocytic, normochromic anemia due to underproduction of erythropoietin (EPO) by the failing kidneys. When anemia is identified in patients with CKD, iron levels should be checked for several reasons: Correctable causes of anemia should be identified; therefore, a basic workup for new anemia should be performed, including evaluation of iron stores, folate and B₁₂ levels, and reticulocyte count, as well as testing for fecal occult blood. In patients with CKD, iron deficiency is common, and red blood cell morphology may be normal early in the deficiency (with a normal mean corpuscular volume). Some patients may require iron supplementation based on low transferrin saturation and ferritin levels. CKD-related hypoproliferative anemia is often treated with EPO-stimulating agents (ESAs), such as supplemental EPO, to stimulate red blood cell production within the bone marrow. However, vigorous hematopoiesis after ESA administration can cause rapid depletion of iron stores, even if iron levels are normal on initiation; therefore, patients who require ESAs (eg, many CKD patients with hemoglobin <10 g/dL) should have iron levels checked prior to initiation of EPO and at scheduled intervals while on therapy (Choice D). (Choice B) Bone marrow biopsy is rarely indicated in the workup of anemia unless abnormal cells (blasts) or pancytopenia is noted. Most common forms of anemia (including CKD-related hypoproliferative anemia) can be evaluated by laboratory tests alone. (Choice C) Serum protein electrophoresis is part of the workup for multiple myeloma; patients typically have new renal dysfunction, anemia, hypercalcemia, and bone pain. This patient has chronic CKD due to her known diabetes and hypertension and does not have hypercalcemia or pain, making this diagnosis unlikely. (Choice E) Low serum folate and B₁₂ levels cause a macrocytic anemia, not a normocytic anemia as seen in this patient. These levels should be checked, but empiric supplementation is not indicated without laboratory-documented deficiency. ₁₂ Educational objective: Patients with advanced chronic kidney disease or end-stage renal disease commonly develop a normocytic anemia due to underproduction of erythropoietin by the failing kidneys. Vigorous hematopoiesis after administration of erythropoiesis-stimulating agents (ESAs) can lead to rapid depletion of iron stores; therefore, all patients who require ESAs should have iron levels checked prior to initiation and at scheduled intervals while on therapy.

Question 20

A 77-year-old man is brought to the physician by his daughter with a 1-week history of gross hematuria.  He has no frequency, urgency, hesitancy, or dribbling.  His other medical problems include hypertension, chronic low back pain, and chronic renal insufficiency.  The patient's medications include amlodipine, hydrochlorothiazide, and acetaminophen with codeine as needed.  He has a 46-pack-year smoking history.  Prostate examination shows no abnormalities.  Laboratory results are as follows:  Urine microscopy shows many normal-appearing red cells, but no dysmorphic red cells or casts.  Urine culture shows no growth.  Prostate-specific antigen is 3.2 ng/mL.  Ultrasound of the kidneys shows bilateral cortical atrophy but no other lesions.  Which of the following is the most appropriate next step in management of this patient?

Accepted Answer

Explanation: 11ec2b69_c093_1dff_8f63_05848c44a6f2_MD0005_00 This patient has a high risk of urinary tract malignancy (eg, renal, bladder, or prostate cancer) in light of gross hematuria, age >40, male gender, and smoking history. Other potential risk factors include history of pelvic radiation or exposure to aniline dyes. Gross hematuria in such patients requires assessment of both the upper and lower urinary tracts. The lower tract is best visualized with cystoscopy, which is highly sensitive for bladder cancer and may identify other potential causes of hematuria as well. Urine cytology is less sensitive than cystoscopy for diagnosing bladder cancer, but it may be considered as an alternate test in low-risk patients (Choice E). The upper tract should also be evaluated. This is usually done with contrast-enhanced computed tomography (CT) urogram, but this test is relatively contraindicated in patients with underlying chronic kidney disease (Choice A). Alternatives to CT include renal ultrasound and magnetic resonance imaging. This patient's ultrasound shows no kidney lesions suggestive of malignancy. (Choice C) Intravenous pyelography has largely been replaced by CT imaging, which has higher sensitivity and specificity in evaluating hematuria. It also requires intravenous contrast, which is contraindicated in this patient. If additional imaging of the upper tract is needed, a retrograde pyelogram can be performed at the time of cystoscopy. (Choice D) Renal biopsy is indicated if there is evidence of glomerular bleeding (eg, red cell casts, dysmorphic red cells) with worsening renal function. It would not be advised in this patient with nonglomerular hematuria. Educational objective: Gross hematuria warrants evaluation of both the upper and lower urinary tracts. Computed tomography urogram is recommended for the upper tract; ultrasound is an alternate test, especially for patients with chronic kidney disease. Cystoscopy is recommended for evaluation of the lower tract, with urine cytology as an alternate test for low-risk patients. References: Diagnostic tests and algorithms used in the investigation of haematuria; systematic reviews and economic evaluation. (http://www.ncbi.nlm.nih.gov/pubmed/16729917) Assessment of hematuria. (http://www.ncbi.nlm.nih.gov/pubmed/21095418)

Exam 1: Advanced Clinical Medicine

What is the most appropriate means of correcting this patient's hyponatremia?