[Clinical features of Q-fever pneumonia].

A retrospective study was undertaken to investigate the clinical aspects of Q-fever pneumonia. Six sporadic cases, 5 men and 1 woman, aged between 36 and 81 years were diagnosed by testing paired serum samples using an indirect immunofluorescence assay from July 2004 to June 2007. Of these, 5 suffered from concomitant or chronic disease. The predominant clinical features were fever, cough, sputum, and chest pain. The WBC count was within normal values in half of the patients. C-reactive protein was elevated in all patients. Liver dysfunction was noted in 2 patients. Chest computed tomography revealed air space consolidation and small nodules in all patients and pleural effusion in 1 patient. Anti-phase II IgG titers of paired serum samples were elevated, but anti-phase II IgM titers were within normal limits in all the patients. Antibiotics were given to all the patients, and, beta-lactum agents were prescribed for 3 patients. The outcome was favorable in all the patients. These patients demonstrated nonspecific clinical, radiological, and laboratory manifestations, and we were able to distinguish Q-type pneumonia from other forms of community-acquired pneumonia only by testing anti-phase II IgG titers of paired serum samples.