[Pulmonary suppuration due to a mixed infection of anaerobic bacterium and Actinomyces]

We report a case of pulmonary suppuration due to a mixed infection of anaerobic bacterium and Actimomyces. A 49-year-old man was admitted to our hospital because of hemoptysis on March 30, 1999. A chest X-ray film showed a localized shadow in the right middle lobe, and a tumor shadow was recognized on chest CT. The anaerobic bacterium were isolated from specimens collected bronchofiberscopically. A diagnosis of pulmonary suppuration due to anaerobic bacterium was made, and treatment with sulbactam/ampicillin, followed by imipenem/cilastatin, was initiated. Although his clinical symptoms and laboratory data improved rapidly following this treatment, the abnormal finding on the chest radiographs remained, with only slight improvement. Accordingly, surgical resection of part of the right middle lobe was performed on June 29 using a video-associated thoracic surgery technique. Actinomycosis was recognized by pathological examination of the resected lesion. A revised diagnosis of pulmonary suppuration due to a mixed infection of anaerobic bacterium and Actinomyces was made. Anaerobic bacterium in the oral cavity are recognized as significant pathogens in pulmonary suppuration. In the present case, we considered anaerobic bacterium and Actinomyces aspirated from the oral cavity into the lung to have caused the pulmonary suppuration.