Fungal and Parasitic Infections USMLE Step 1 Practice Question
An 18-year-old female with a pet cat presents to clinic with a 3-week history of fever (38.5°C), malaise, and tender left axillary lymphadenopathy. She recalls a cat scratch on her left forearm approximately 3 weeks prior. On examination, she has a small, indurated, painless papule at the scratch site with significant regional lymphadenopathy. She denies constitutional symptoms beyond the fever. Laboratory studies show a normal white blood cell count with normal differential. Serologic testing is positive for Bartonella henselae antibodies. Which of the following is the most likely diagnosis?
Answer choices
- AMycobacterium marinum infection with sporotrichoid lymphangitis
- BCat scratch disease (Bacillary angiomatosis)
- CToxoplasmosis with regional lymphadenopathy
- DSporotrichosis with lymphangitic spread
- ECat scratch disease (Bartonella henselae) with regional lymphadenopathyCorrect answer
- FAcute lymphangitis from Streptococcus pyogenes with systemic infection
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