[Acute Q fever: study of 23 patients (author's transl)].

Twenty-three patients with Q fever who were diagnosed over a 3 year period are described. The majority came from the Madrid urban area and less than half had epidemiological antecedents. Nine patients presented with pulmonary infiltrations, 12 with suppressed fever and in 2 criteria for fever of unknown origin were met. The majority had clinical or analytic data of hepatic disease and liver biopsy practiced in 4 patients showed granulomas. Diagnosis was established through the increment of seric antibodies against antigens of phase II C. burnetii, detected by complement fixation test. Acute Q fever is not a rare disease in our environment and must be taken into account when a differential diagnosis is looked for in processes such as fever of short evolution, fever of unknown origin, pneumoniae and granulomatous hepatitis.