[A case of nocardiosis with associated endobronchial excavated lesions]

A case of nocardiosis with associated endobronchial excavated lesions is reported. A 79-year-old woman was diagnosed as having dermatomyositis in March, 2010. She was started on prednisolone (50mg/day) and was then switched to betamethasone due to lower limb edema and tapered to a dose of 2.5mg/day. A periodic chest X-ray examination in July, 2010, incidentally revealed nodular densities and associated cavities in the upper right lung field. On thoracoabdominal computed tomography (CT), bilateral pulmonary nodular shadows with various-sized cavities and multiple, new, intrahepatic, low-density regions were also identified. On bronchoscopy, a white, excavated lesion resembling an ulcerous lesion was observed in the left upper lobe bronchus, and a small exophytic lesion was observed in the right B6 bronchus. Nocardia asteroides complex was isolated from cultures of bronchial lavage fluid and sputum. The patient was treated with 4 weeks of intravenous imipenem (1.5g/day), followed by oral minocycline therapy (200mg/day) for 6 months, after which lesion resolution was confirmed on CT and treatment was discontinued. No recurrence has been reported in the roughly 18 months of follow-up to date. Nocardiosis results from infection with bacteria of the zoonotic, aerobic, Actinomyces genus and presents with disseminated lesions. Reported cases of human infection are increasing due to greater numbers of immunocompromised patients and improved diagnostic techniques. However, nocardiosis involving endobronchial lesions is extremely rare, and, to the best of our knowledge, the present case is the first report of endobronchial excavated lesions caused by nocardiosis.