ID Board Review Questions

1. ID Board Review Questions Emily Landon Mawdsley, MD 5/3/10

2. A 25-year-old woman who is 28 weeks pregnant has a positive urine culture detected during a routine prenatal visit. She has not had fever, urinary frequency, or dysuria and is not taking any medications other than prenatal vitamins. She has never had a urinary tract infection before and has no medical problems. On physical examination, vital signs, including temperature, are normal. There is no costovertebral angle tenderness. The urine culture shows greater than 105 colony-forming units/mL of Escherichia coli that are sensitive to nitrofurantoin and ciprofloxacin but resistant to cefazolin, trimethoprim-sulfamethoxazole, and ampicillin. Which of the following is the most appropriate treatment? A) Ampicillin B) Ciprofloxacin C) Nitrofurantoin D) Trimethoprim E) Observation

3. A 25-year-old woman who is 28 weeks pregnant has a positive urine culture detected during a routine prenatal visit. She has not had fever, urinary frequency, or dysuria and is not taking any medications other than prenatal vitamins. She has never had a urinary tract infection before and has no medical problems. On physical examination, vital signs, including temperature, are normal. There is no costovertebral angle tenderness. The urine culture shows greater than 105 colony-forming units/mL of Escherichia coli that are sensitive to nitrofurantoin and ciprofloxacin but resistant to cefazolin, trimethoprim-sulfamethoxazole, and ampicillin. Which of the following is the most appropriate treatment? A) Ampicillin B) Ciprofloxacin C) Nitrofurantoin D) Trimethoprim E) Observation

4. A 57-year-old man is evaluated for a 2-day history of fever, severe myalgia, and a frontal headache. He denies cough, diarrhea, abdominal pain, or urinary tract symptoms. He returned 1 week ago from a vacation in Puerto Rico. He slept in a well-screened room under mosquito netting. On physical examination, the patient is moderately ill appearing. Temperature is 39.2 °C (102.6 °F), blood pressure is 108/75 mm Hg, pulse rate is 96/min, and respiration rate is 18/min. There is a maculopapular rash on his trunk. The remainder of the examination is normal. Laboratory studies: Hemoglobin 14.8 g/dL (148 g/L), Leukocyte count 3700/µL (3.7 × 109/L), Platelet count 99,000/µL (99 × 109/L), Creatinine 1.1 mg/dL (97.2 µmol/L), Alanine aminotransferase 84 U/L, Aspartate aminotransferase 92 U/L, INR1.1, Activated partial thromboplastin time 27 s, Urinalysis Normal Which of the following is the most likely diagnosis? A) Chikungunya B) Dengue C) Influenza D) Malaria E) Typhoid fever

5. A 57-year-old man is evaluated for a 2-day history of fever, severe myalgia, and a frontal headache. He denies cough, diarrhea, abdominal pain, or urinary tract symptoms. He returned 1 week ago from a vacation in Puerto Rico. He slept in a well-screened room under mosquito netting. On physical examination, the patient is moderately ill appearing. Temperature is 39.2 °C (102.6 °F), blood pressure is 108/75 mm Hg, pulse rate is 96/min, and respiration rate is 18/min. There is a maculopapular rash on his trunk. The remainder of the examination is normal. Laboratory studies: Hemoglobin 14.8 g/dL (148 g/L), Leukocyte count 3700/µL (3.7 × 109/L), Platelet count 99,000/µL (99 × 109/L), Creatinine 1.1 mg/dL (97.2 µmol/L), Alanine aminotransferase 84 U/L, Aspartate aminotransferase 92 U/L, INR1.1, Activated partial thromboplastin time 27 s, Urinalysis Normal Which of the following is the most likely diagnosis? A) Chikungunya B) Dengue C) Influenza D) Malaria E) Typhoid fever

6. A 70-year-old man is evaluated in the emergency department with the acute onset of fever, rigors, and productive cough. The patient has a history of diabetes mellitus and chronic obstructive pulmonary disease treated with glyburide, metformin, albuterol, and tiotropium and a severe penicillin allergy that leads to anaphylaxis. On physical examination, the patient appears confused. The temperature is 40.0 oC (104.0 oF), blood pressure is 90/60 mm Hg, pulse rate is 120/min, and respiration rate is 34/min. Pulmonary examination reveals diffuse rhonchi in both lung fields. Laboratory studies: Leukocyte count 3000/µL (3 × 109/L) with 50% band forms, Platelet count 80,000/µL (80 × 109/L), Blood urea nitrogen 40 mg/dL (14.3 mmol/L), Creatinine 2.1 mg/dL (185.6 µmol/L) A chest radiograph reveals right lower lobe and left lingular infiltrates. The patient is admitted to the intensive care unit. Which of the following empiric antimicrobial regimens should be initiated? A) Azithromycin plus cefotaxime B) Levofloxacin plus aztreonam C) Trimethoprim-sulfamethoxazole D) Vancomycin plus gentamicin

7. A 70-year-old man is evaluated in the emergency department with the acute onset of fever, rigors, and productive cough. The patient has a history of diabetes mellitus and chronic obstructive pulmonary disease treated with glyburide, metformin, albuterol, and tiotropium and a severe penicillin allergy that leads to anaphylaxis. On physical examination, the patient appears confused. The temperature is 40.0 oC (104.0 oF), blood pressure is 90/60 mm Hg, pulse rate is 120/min, and respiration rate is 34/min. Pulmonary examination reveals diffuse rhonchi in both lung fields. Laboratory studies: Leukocyte count 3000/µL (3 × 109/L) with 50% band forms, Platelet count 80,000/µL (80 × 109/L), Blood urea nitrogen 40 mg/dL (14.3 mmol/L), Creatinine 2.1 mg/dL (185.6 µmol/L) A chest radiograph reveals right lower lobe and left lingular infiltrates. The patient is admitted to the intensive care unit. Which of the following empiric antimicrobial regimens should be initiated? A) Azithromycin plus cefotaxime B) Levofloxacin plus aztreonam C) Trimethoprim-sulfamethoxazole D) Vancomycin plus gentamicin

8. A 35-year-old man is evaluated in the emergency department for a 1-month history of chronic cough productive of blood-tinged sputum. He admits to frequent encounters with commercial sex-workers while visiting Russia, India, and Thailand. On physical examination, temperature is 38.8 °C (100.9 °F), blood pressure is 90/50 mm Hg, pulse rate is 95/min, and respiration rate is 30/min. Thrush is noted on oral examination. Crackles are heard over the upper lung fields. Bilateral upper lobe cavitary lesions are present on a chest radiograph. Acid-fast bacillus is found on the direct sputum smear. Which of the following is the best treatment option? A) Ciprofloxacin, pyrazinamide, ethambutol, ethionamide, and cycloserine B) Isoniazid C) Isoniazid and rifampin D) Isoniazid, rifampin, pyrazinamide, and ethambutol

9. A 35-year-old man is evaluated in the emergency department for a 1-month history of chronic cough productive of blood-tinged sputum. He admits to frequent encounters with commercial sex-workers while visiting Russia, India, and Thailand. On physical examination, temperature is 38.8 °C (100.9 °F), blood pressure is 90/50 mm Hg, pulse rate is 95/min, and respiration rate is 30/min. Thrush is noted on oral examination. Crackles are heard over the upper lung fields. Bilateral upper lobe cavitary lesions are present on a chest radiograph. Acid-fast bacillus is found on the direct sputum smear. Which of the following is the best treatment option? A) Ciprofloxacin, pyrazinamide, ethambutol, ethionamide, and cycloserine B) Isoniazid C) Isoniazid and rifampin D) Isoniazid, rifampin, pyrazinamide, and ethambutol

10. A 25-year-old man is brought to the emergency department because of a 1-day history of fever and progressive delirium. On physical examination, temperature is 38.5 °C (101.3 °F), blood pressure is 86/58 mm Hg, pulse rate is 122/min, and respiration rate is 34/min. The patient is oriented only to person. On pulmonary examination, he demonstrates increased work of breathing. There is no lymphadenitis. Abdominal examination is normal. The leukocyte count is 32,000/µL (32 × 109/L). A chest radiograph shows bilateral diffuse alveolar infiltrates. An initial blood smear shows small gram-negative coccobacilli, and special stains show bacteria that look like safety pins. Infection with which of the following organisms is most likely? A Francisella tularensis B Salmonella enterica C Staphylococcus aureus D Streptococcus pneumoniae E Yersinia pestis

11. A 25-year-old man is brought to the emergency department because of a 1-day history of fever and progressive delirium. On physical examination, temperature is 38.5 °C (101.3 °F), blood pressure is 86/58 mm Hg, pulse rate is 122/min, and respiration rate is 34/min. The patient is oriented only to person. On pulmonary examination, he demonstrates increased work of breathing. There is no lymphadenitis. Abdominal examination is normal. The leukocyte count is 32,000/µL (32 × 109/L). A chest radiograph shows bilateral diffuse alveolar infiltrates. An initial blood smear shows small gram-negative coccobacilli, and special stains show bacteria that look like safety pins. Infection with which of the following organisms is most likely? A Francisella tularensis B Salmonella enterica C Staphylococcus aureus D Streptococcus pneumoniae E Yersinia pestis

12. A 70-year-old man is evaluated in January for a 2-day history of fever and cough productive of yellow sputum. He was well until 10 days ago when he developed headache, myalgia, and coryza. He seemed to be improving by day 8 of his illness, but he then developed his current symptoms. Medical history is significant for hypertension and chronic obstructive pulmonary disease treated with hydrochlorothiazide, albuterol, and tiotropium. On physical examination, temperature is 38.9 oC (102.0 oF), blood pressure is 110/70 mm Hg, pulse rate is 100/min, and respiration rate is 22/min. Pulmonary examination reveals crackles at the left lung base. Laboratory studies indicate a leukocyte count of 15,000/µL (15 × 109/L) with 20% band forms. Chest radiograph reveals a left lower lobe infiltrate. Which of the following empiric antimicrobial regimens should be initiated? A) Azithromycin plus ceftriaxone B) Clindamycin plus levofloxacin C) Piperacillin-tazobactam D) Vancomycin plus levofloxacin

13. A 70-year-old man is evaluated in January for a 2-day history of fever and cough productive of yellow sputum. He was well until 10 days ago when he developed headache, myalgia, and coryza. He seemed to be improving by day 8 of his illness, but he then developed his current symptoms. Medical history is significant for hypertension and chronic obstructive pulmonary disease treated with hydrochlorothiazide, albuterol, and tiotropium. On physical examination, temperature is 38.9 oC (102.0 oF), blood pressure is 110/70 mm Hg, pulse rate is 100/min, and respiration rate is 22/min. Pulmonary examination reveals crackles at the left lung base. Laboratory studies indicate a leukocyte count of 15,000/µL (15 × 109/L) with 20% band forms. Chest radiograph reveals a left lower lobe infiltrate. Which of the following empiric antimicrobial regimens should be initiated? A) Azithromycin plus ceftriaxone B) Clindamycin plus levofloxacin C) Piperacillin-tazobactam D) Vancomycin plus levofloxacin

14. A 19-year-old male college student has a 2-day history of a urethral discharge and a burning sensation on urination. He has had three female sexual partners in the past month. Physical examination discloses a scant mucoid discharge from the urethral orifice. No rashes or other lesions are seen. Gram stain of the urethral secretions shows greater than 12 polymorphonuclear cells/hpf. No intra- or extracellular organisms are seen. Which of the following is the most appropriate treatment? A) Acyclovir orally B) Azithromycin orally C) Benzathine penicillin G, intramuscularly D) Cefixime orally E) Metronidazole orally

15. A 19-year-old male college student has a 2-day history of a urethral discharge and a burning sensation on urination. He has had three female sexual partners in the past month. Physical examination discloses a scant mucoid discharge from the urethral orifice. No rashes or other lesions are seen. Gram stain of the urethral secretions shows greater than 12 polymorphonuclear cells/hpf. No intra- or extracellular organisms are seen. Which of the following is the most appropriate treatment? A) Acyclovir orally B) Azithromycin orally C) Benzathine penicillin G, intramuscularly D) Cefixime orally E) Metronidazole orally

16. A 25-year-old man is evaluated for a 2-week history of left-sided facial pain. Medical history is unremarkable. A diagnosis of sinusitis is established, and the patient receives therapy with azithromycin, which partially resolves his pain. One week after initiation of therapy, he is admitted to the emergency department with headache and a tonic-clonic seizure. On physical examination, temperature is normal, and he is drowsy. There are no focal neurologic deficits. Laboratory studies are normal. An MRI shows a 3.5-cm ring-enhancing lesion in the left frontoparietal region. Aspiration of the lesion reveals purulent material. Empiric therapy with vancomycin, metronidazole, and ceftriaxone is initiated. Culture of the aspirate grows only Escherichia coli. Which of the following is the most appropriate treatment? A) Change antimicrobial therapy to imipenem B) Change antimicrobial therapy to levofloxacin C) Continue ceftriaxone only D) Continue metronidazole and ceftriaxone only E) Continue vancomycin, metronidazole, and ceftriaxone

17. A 25-year-old man is evaluated for a 2-week history of left-sided facial pain. Medical history is unremarkable. A diagnosis of sinusitis is established, and the patient receives therapy with azithromycin, which partially resolves his pain. One week after initiation of therapy, he is admitted to the emergency department with headache and a tonic-clonic seizure. On physical examination, temperature is normal, and he is drowsy. There are no focal neurologic deficits. Laboratory studies are normal. An MRI shows a 3.5-cm ring-enhancing lesion in the left frontoparietal region. Aspiration of the lesion reveals purulent material. Empiric therapy with vancomycin, metronidazole, and ceftriaxone is initiated. Culture of the aspirate grows only Escherichia coli. Which of the following is the most appropriate treatment? A) Change antimicrobial therapy to imipenem B) Change antimicrobial therapy to levofloxacin C) Continue ceftriaxone only D) Continue metronidazole and ceftriaxone only E) Continue vancomycin, metronidazole, and ceftriaxone

18. A 35-year-old male customs inspector is brought to the emergency department because of a 2-day history of fever, shortness of breath, and chest pain. He has had no recent known contact with ill persons. On physical examination, the patient is diaphoretic and appears acutely ill. He is oriented only to person. Temperature is 38.0 °C (100.4 °F), blood pressure is 88/60 mm Hg, pulse rate is 110/min, and respiration rate is 28/min. Coarse bronchial breath sounds are heard. The leukocyte count is 15,000/µL (15 × 109/L). A chest radiograph shows a widened mediastinum and bilateral pleural effusions. A buffy coat Gram stain of a peripheral blood smear shows box car–shaped gram-positive bacilli. Which of the following is the most appropriate treatment? A) Ciprofloxacin, rifampin, and vancomycin B) Erythromycin, clindamycin, and rifampin C) Erythromycin, vancomycin, and rifampin D) Penicillin, rifampin, and vancomycin

19. A 35-year-old male customs inspector is brought to the emergency department because of a 2-day history of fever, shortness of breath, and chest pain. He has had no recent known contact with ill persons. On physical examination, the patient is diaphoretic and appears acutely ill. He is oriented only to person. Temperature is 38.0 °C (100.4 °F), blood pressure is 88/60 mm Hg, pulse rate is 110/min, and respiration rate is 28/min. Coarse bronchial breath sounds are heard. The leukocyte count is 15,000/µL (15 × 109/L). A chest radiograph shows a widened mediastinum and bilateral pleural effusions. A buffy coat Gram stain of a peripheral blood smear shows box car–shaped gram-positive bacilli. Which of the following is the most appropriate treatment? A) Ciprofloxacin, rifampin, and vancomycin B) Erythromycin, clindamycin, and rifampin C) Erythromycin, vancomycin, and rifampin D) Penicillin, rifampin, and vancomycin

20. A 27-year-old previously healthy woman is diagnosed with community-acquired pneumonia for which she receives ceftriaxone therapy. Medical history is otherwise noncontributory. Routine and mycobacterial sputum cultures are performed. The patient recovers uneventfully over the subsequent 2 weeks, and a follow-up chest radiograph shows improvement. The routine sputum cultures reveal only normal flora; however, after 3 weeks, the mycobacterial culture grows two colonies of Mycobacterium avium complex. Which of the following is the most appropriate next step in management? A) Initiate clarithromycin, rifampin, and ethambutol B) Initiate isoniazid C) Initiate isoniazid, rifampin, pyrazinamide, and ethambutol D) No further treatment

21. A 27-year-old previously healthy woman is diagnosed with community-acquired pneumonia for which she receives ceftriaxone therapy. Medical history is otherwise noncontributory. Routine and mycobacterial sputum cultures are performed. The patient recovers uneventfully over the subsequent 2 weeks, and a follow-up chest radiograph shows improvement. The routine sputum cultures reveal only normal flora; however, after 3 weeks, the mycobacterial culture grows two colonies of Mycobacterium avium complex. Which of the following is the most appropriate next step in management? A) Initiate clarithromycin, rifampin, and ethambutol B) Initiate isoniazid C) Initiate isoniazid, rifampin, pyrazinamide, and ethambutol D) No further treatment

22. A 42-year-old woman is evaluated for a postoperative wound infection. Eight weeks ago, the patient underwent bilateral augmentation mammoplasty. Six weeks after surgery, she developed violaceous draining nodules at the surgical closure site of the right breast. After 7 days of dicloxacillin, the wound had enlarged. Wound cultures grew normal skin flora. The patient was hospitalized, and intravenous vancomycin plus cefepime was added but without clinical benefit. A second set of wound cultures grew a few colonies of Candida albicans. Medical history is otherwise unremarkable. On physical examination, temperature is 38.0 °C (100.4 °F), blood pressure is 105/75 mm Hg, pulse rate is 84/min, and respiration rate is 16/min. Her left breast surgical scar is well healed, and the right breast surgical wound is partially opened and packed along the medial half. The lateral half of the wound is erythematous, with two sinus tracts draining purulent material. Which of the following is the most likely causative agent for her wound infection? A) Fluconazole-resistant Candida albicans B) Methicillin-resistant Staphylococcus aureus C) Mycobacterium abscessus D) Mycobacterium tuberculosis E) Nocardia asteroides

23. A 42-year-old woman is evaluated for a postoperative wound infection. Eight weeks ago, the patient underwent bilateral augmentation mammoplasty. Six weeks after surgery, she developed violaceous draining nodules at the surgical closure site of the right breast. After 7 days of dicloxacillin, the wound had enlarged. Wound cultures grew normal skin flora. The patient was hospitalized, and intravenous vancomycin plus cefepime was added but without clinical benefit. A second set of wound cultures grew a few colonies of Candida albicans. Medical history is otherwise unremarkable. On physical examination, temperature is 38.0 °C (100.4 °F), blood pressure is 105/75 mm Hg, pulse rate is 84/min, and respiration rate is 16/min. Her left breast surgical scar is well healed, and the right breast surgical wound is partially opened and packed along the medial half. The lateral half of the wound is erythematous, with two sinus tracts draining purulent material. Which of the following is the most likely causative agent for her wound infection? A) Fluconazole-resistant Candida albicans B) Methicillin-resistant Staphylococcus aureus C) Mycobacterium abscessus D) Mycobacterium tuberculosis E) Nocardia asteroides

24. A 20-year-old male college student is evaluated for a 3-day history of intermittent fever and rigors as well as vomiting, diarrhea, and severe headache. Two weeks ago, he returned from a 20-day African safari in Kenya and Tanzania. He sought no medical advice about immunizations or other prophylaxis prior to the trip. On physical examination, the patient is not ill appearing. Temperature is 39.0 °C (102.2 °F), blood pressure is 105/70 mm Hg, pulse rate is 100/min, and respiration rate is 22/min. The remainder of the examination is normal. Laboratory studies: Hemoglobin 14.5 g/dL (145 g/L), Leukocyte count 3700/µL (3.7 × 109/L), Platelet count 95,000/µL (95 × 109/L), Glucose 85 mg/dL (4.7 mmol/L) A malaria smear shows greater than 5% parasitemia with only ring forms present. Which of the following is the most appropriate treatment? A) Chloroquine B) Pyrimethamine-sulfadoxine C) Quinine and doxycycline D) Quinine and doxycycline followed by primaquine

25. A 20-year-old male college student is evaluated for a 3-day history of intermittent fever and rigors as well as vomiting, diarrhea, and severe headache. Two weeks ago, he returned from a 20-day African safari in Kenya and Tanzania. He sought no medical advice about immunizations or other prophylaxis prior to the trip. On physical examination, the patient is not ill appearing. Temperature is 39.0 °C (102.2 °F), blood pressure is 105/70 mm Hg, pulse rate is 100/min, and respiration rate is 22/min. The remainder of the examination is normal. Laboratory studies: Hemoglobin 14.5 g/dL (145 g/L), Leukocyte count 3700/µL (3.7 × 109/L), Platelet count 95,000/µL (95 × 109/L), Glucose 85 mg/dL (4.7 mmol/L) A malaria smear shows greater than 5% parasitemia with only ring forms present. Which of the following is the most appropriate treatment? A) Chloroquine B) Pyrimethamine-sulfadoxine C) Quinine and doxycycline D) Quinine and doxycycline followed by primaquine