An adult case of pneumonia due to Mycoplasma pneumoniae and Chlamydia psittaci

: A 18-year-old male was admitted to another hospital complaining of his chest X-ray. After transfer to our hospital, increased serum antibody titers to simultaneous M. pneumoniae and C. psittaci were noted. These antibody titers decreased after about four months. Positive results for M. pneumoniae was obtained by Polymerase chain reaction in the right pleural effusion. Based on these findings, this case was diagnosed as M. pneumoniae and C. psittaci pneumonia. A transbronchial lung biopsy and a bronchial biopsy revealed rare histological findings, including histiocytic intra-alveolar pneumonia with palisaded granuloma and small foci of necrosis in the left upper lobe and eosinophilic bronchitis in the right middle bronchus. His chest X-ray and chest CT showed a nodular shadow, obstructive pneumonia and pleural effusion which are rare in M. pneumoniae and C., psittaci pneumonia.