A 56-year-old man from Missouri presents in July with fever (39.2°C), malaise, and frontal headache 6 days after removing a tick from his leg. Vital signs show BP 128/82 mmHg, HR 94/min, RR 18/min, SpO2 98% on room air. Laboratory studies reveal leukopenia (WBC 3.2K/μL), thrombocytopenia (platelets 98K/μL), elevated transaminases (AST 156 U/L), and basophilic inclusions within monocytes on blood smear. He denies rash. Which organism is most likely responsible?
- A)Anaplasma phagocytophilum
- B)Ehrlichia chaffeensisGABARITO
- C)Rickettsia rickettsii
- D)Coxiella burnetii
- E)Borrelia burgdorferi
Explicação
Ehrlichia chaffeensis is correct. Ehrlichiosis produces fever, cytopenias, transaminitis, and morulae in monocytes after tick exposure, especially in the south central and southeastern United States. The absence of a classic rash and the monocyte finding are k... Ver explicação completa e trilha adaptativa →