Q fever endocarditis: a diagnostic challenge in a complex cardiological case.
Riccardo Rovelli, Elisa Brangi, Francesca Capasso et al.
✦ AI-curated · Sources linked
Case in brief
A 73-year-old woman with coronary artery disease and systemic sclerosis presented with asthenia and dyspnea. Echocardiography showed a highly mobile, pedunculated mitral-valve mass suggestive of endocarditis. Repeated blood cultures were negative, while serology was positive for Coxiella burnetii (IgG phase I 1:128), supporting a diagnosis of Q fever endocarditis. Doxycycline and hydroxychloroquine were started but discontinued after renal impairment and thrombocytopenia developed. Her course was complicated by cardiac arrest, and she died.
What made this case unusual
The mitral-valve mass was highly mobile and pedunculated, while repeated blood cultures remained negative; Coxiella burnetii serology established the diagnosis.
Diagnostic / clinical pearl
In suspected endocarditis with persistently negative blood cultures, consider Q fever and use serological testing for Coxiella burnetii as part of the diagnostic workup.