RESUMO
Query (Q) fever is a worldwide infectious disease with acute and chronic manifestations caused by Coxiella burnetii. The clinical manifestations are so variable that the disease is often only diagnosed if systematically considered as a differential diagnosis. Here, we present a case of a 39-year-old man who lived in a countryside house, with cattle and sheep in his field, with acute Q fever hepatitis with the typical granulomatous arrangement in the liver biopsy. The diagnosis was confirmed by polymerase chain reaction (PCR) assay in a serum sample and the presence of phase II antibodies. Anticardiolipin antibody (aCL) determination at diagnosis of acute Q fever and during follow-up was made to persecute early identification and to guide the treatment and prophylaxis of possible complications, such as endocarditis.