MCQ Book Questions

Q60262. A 24-year-old woman develops an expanding erythematous skin lesion after hiking through the woods in Connecticut. The rash disappears, but 1 year later, the patient develops arthralgias and right facial nerve palsy. Which of the following is the most likely etiologic agent responsible for this patient’s symptoms?

Q60263. A 59-year-old man with colon cancer is treated with chemotherapy. Two months later, he develops increasing cough and respiratory distress. A chest X-ray shows diffuse bilateral interstitial infi ltrates. Sputum cultures are nega- tive, and the patient does not respond to antibiotic therapy. A lung biopsy reveals acute and chronic interstitial pneu- monitis. There are enlarged cells with prominent, dark-blue nuclear inclusions (shown in the image). Which of the fol- lowing is most likely responsible for this patient’s pulmo- nary condition?

Q60264. A 6-month-old female infant is brought to the physician with a 2-day history of severe cough, wheezing, and respiratory distress. Physical examination shows rhinitis, mild cyanosis, and fever. Which of the following is the most likely etiology of this child’s pulmonary infection?

Q60265. A 75-year-old woman died in February of respiratory fail- ure after a febrile disease of 1 week in duration. An autopsy shows necrotizing bronchitis and diffuse, hemorrhagic necrotizing pneumonia. Which of the following pathogens was most likely responsible for this patient’s fatal pulmonary infection?

Q60266. A 30-year-old woman presents with persistent dry cough, fatigue, and low-grade fever. Physical examination shows marked pallor, respiratory distress, nasal fl aring, and intercos- tal retractions. A chest X-ray reveals diffuse, bilateral intersti- tial infi ltrates. A photomicrograph of bronchoalveolar lavage is shown. Which of the following etiologic agents is most likely responsible for this patient’s pulmonary disease?

Q60267. A 28-year-old man presents with sudden onset of fever, chills, and a productive cough with blood-tinged sputum. His past medical history is signifi cant for a splenectomy following a motor vehicle accident 3 years ago. An X-ray of the chest demonstrates consolidation of the right middle lobe. Sputum culture shows Gram-positive diplococci. Which of the fol- lowing is the most likely cause of this patient’s respiratory infection?

Q60268. A 37-year-old man is admitted to the hospital with a produc- tive cough, fever, and night sweats. An X-ray fi lm of the chest shows an ill-defi ned area of consolidation at the periphery of the right middle lobe and mediastinal lymphadenopathy. Sputum culture grows acid-fast bacilli. Lymph node biopsy in this patient would most likely show which of the following pathologic fi ndings?

Q60269. A 24-year-old woman with insulin-dependent (type 1) diabetes mellitus presents to the emergency room with severe respira- tory distress and pleuritic chest pain. The patient has a history of antibiotic-resistant sinusitis. Physical examination reveals periorbital edema and a mucopurulent postnasal discharge. Despite therapy, the patient dies of acute respiratory failure. Cross section of the lung at autopsy shows hemorrhagic infarction. The vessel in the center of the fi eld is occluded by a septic thrombus (shown in the image). These clinicopatho- logic features are typical of which of the following pulmonary diseases?

Q60270. A 4-year-old girl, whose parents recently immigrated from Ecuador, presents with high fever, cough, and skin rash of 3 days in duration. Her parents report that her rash began in the form of pink papules behind the ears and spread around her body. Physical examination shows an extensive maculo- papular rash over the child’s face, neck, trunk, and limbs. She displays small white spots on buccal surfaces. This patient’s skin rash is most likely caused by infection with which of the following agents?

Q60271. A 50-year-old woman presents with increasing dry cough and shortness of breath that has lasted for 3 weeks. She is a bird fancier, and her house is fi lled with parrots. An X-ray fi lm of the chest shows diffuse lung infi ltrates. Sputum cultures are negative, and the patient does not respond to antibiotic therapy. A transbronchial aspirate reveals chronic interstitial pneumonia. The patient responds well to tetracycline. Which of the following is the most likely etiologic agent responsible for this patient’s symptoms?

Q60272. A 5-year-old boy dies of respiratory insuffi ciency and compli- cations of pneumonia. Histologic examination of the lungs at autopsy shows giant cells with up to 100 nuclei (shown in the image). Which of the following viruses most likely caused this child’s fatal respiratory tract infection?

Q60273. A 31-year-old man with AIDS complains of painful swallow- ing. Physical examination of his oral cavity demonstrates a whitish membrane covering much of his tongue and palate. Endoscopic examination reveals the same whitish membrane covering his esophageal mucosa. An endoscopic biopsy is shown in the image. Which of the following is the most likely etiologic agent responsible for this patient’s symptoms?

Q60274. A 35-year-old man with AIDS presents to the emergency room with a 2-week history of progressive weight loss and produc- tive cough with bloody sputum. An X-ray fi lm of the chest shows a cavitary lesion in the right middle lobe. A smear of the sputum reveals many acid-fast rods. Which of the following is the most likely diagnosis?

Q60275. A 1-year-old girl is brought to the clinic in January by her parents because of a fever, runny nose, congestion, “bark- ing” cough, and diffi culty breathing. Physical examination shows a red throat. Parainfl uenza virus is isolated. Which of the following is chiefl y responsible for the barking cough and inspiratory stridor seen in this patient?

Q60276. A 7-year-old black girl with sickle cell anemia presents with sudden onset of fatigue and joint pain. Physical examination shows marked pallor of the skin and mucous membranes and arthralgias of the lower limbs. The mother indicated that the child had recently recovered from a minor “fl u.” The CBC shows pancytopenia. Which of the following agents is respon- sible for this patient’s symptoms?

Q60277. A 2-day-old premature infant develops tonic-clonic seizures in the nursery. A CT scan of the head shows microcalcifi cations. Three days later, the neonate dies. The brain at autopsy reveals large areas of subependymal necrosis with calcifi cation (shown in the image, see arrows). Which of the following pathogens is the most likely cause of death in this neonate?

Q60278. A 2-month-old infant presents with fever to 38.6°C (103°F) and neck rigidity. Cerebrospinal fl uid shows numerous neu- trophils, decreased glucose, and increased protein. Gram- positive cocci are present. Which of the following is the most likely cause of meningitis in this neonate?

Q60279. A 24-year-old woman presents with severe vomiting, abdomi- nal cramps, and diarrhea 2 hours after dining at a local restau- rant. Many of the customers that night reported similar symp- toms. Which of the following mechanisms of disease is chiefl y responsible for the development of gastrointestinal symptoms in this patient?

Q60280. A 48-year-old man with AIDS is admitted to the hospital with a fever of 38°C (103°F), night sweats, persistent cough, and prolonged diarrhea. His CD4 cell count is less than 300/μL. Stool culture reveals the presence of acid-fast bacilli. Which of the following pathogens is responsible for this patient’s respi- ratory and gastrointestinal disease?

Q60281. A 14-year-old girl presents with yellow and red crusted lesions around her mouth and arms (shown in the image). She has a recent history of intermittent low-grade fever. This patient’s skin lesions are most likely caused by which of the following microorganisms?