Organ System Pathology USMLE Step 1 Practice Question
A 31-year-old woman with photosensitive malar rash, recurrent oral ulcers, and polyarthralgias presents with dyspnea on exertion. Vital signs: BP 128/82, HR 98, RR 18, Temp 37.2°C, SpO2 98% on room air. Physical examination reveals a new holosystolic murmur. Echocardiography demonstrates small sterile vegetations on both mitral valve leaflets. Blood cultures remain negative. Antinuclear antibody titer is markedly elevated. Which of the following is the most likely diagnosis?
Answer choices
- AAcute rheumatic valvulitis
- BNonbacterial thrombotic endocarditis associated with malignancy
- CLibman Sacks endocarditisCorrect answer
- DPapillary fibroelastoma
- EInfective endocarditis due to viridans streptococci
- FMarantic endocarditis associated with systemic lupus erythematosus
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