[Clinical features of Q fever pneumonia].

We report four cases of Q fever pneumonia diagnosed using PanBio Coxilla burnetii ELISA. The patients, a 21-year-old woman, a 53-year-old man, a 74-year-old man and a 87-year-old man, were among 284 with community-acquired pneumonia who were treated as inpatients from March 2001 till March 2003. The frequency of Q fever pneumonia in community-acquired pneumonia was 1.4%. The 21-year-old woman was a typical case of Q fever pneumonia, since her clinical features showed 1. the breeding of cats, 2. development from a fever and non-productive caught in March, 3. multiple soft consolidations in the chest radiograph, 4. normal WBC count, 5. cure by administration of clarithromycin. The pneumonias of the other 3 cases were considered to be mixed infections, with bacteria such as Streptococcus pneumoniae and Haemophilus influenzae. Their clinical features were 1. elderly male patients with underlying diseases, 2. development from fever and cough with purulent sputum in winter, 3. coarse crackle on auscultation, 4. consolidation with pleural effusion in chest radiograph, 5. leukocytosis, elevation of BUN, hyponatremia, 6. a few cases with unfavorable prognoses despite medication with carbapenem and minocycline. These findings suggested that two types of pneumonia exist; one with the usual features of atypical pneumonia, and the other presenting the clinical features of bacterial pneumonia of the elderly due to a mixed infection including C. burnetti.