Clinical and radiographic characteristics of 12 patients with Mycobacterium abscessus pulmonary disease

Background: Mycobacterium abscessus is the most common respiratory pathogen in rapidly growing mycobacteria and is resistant to all of the first-line antituberculosis drugs. This report describes the clinical and radiographic characteristics in patients with pulmonary disease caused by M. abscessus. Materials and Methods: Twelve patients with pulmonary disease caused by M. abscessus who fulfilled the 1997 American Thoracic Society diagnostic criteria for a nontuberculous mycobacterial pulmonary infection were observed over a five-and-a-half year period. The clinical characteristics and chest radiographic findings were analyzed, retrospectively. Results: The patients were predominantly female(11/12, 92%) and nonsmokers(12/12, 100%). Coughing (10/12, 83%), sputum(10/12, 83%) and hemoptysis(10/12, 83%) were the common symptoms and they had prolonged periods from the onset of symptoms to the diagnosis of their disease(median 6.5 years). Eleven (92%) patients had a previous history of being treated for pulmonary tuberculosis. The sputum specimens were acid-fast bacilli smear-positive in all patients. All patients were administered antituberculosis drugs. Six (50%) patients were treated with second-line antituberculosis drugs on account of persistent smear-positive sputum specimens. The chest radiographs showed that reticulonodular opacities(11/12, 92%) were the most common pattern of abnormality, followed by cavitary lesions(5/12, 42%). The computed tomography findings suggested bronchiolitis from the centrilobular nodules with a tree-in-bud appearances(9/10, 90%) and bronchiectasis (9/10, 90%) were the most common, followed by well-defined nodules smaller than 10-mm in diameter(7/10, 70%). Conclusions: M. abscessus pulmonary disease should be recognized as a cause of chronic mycobacterial lung disease, and respiratory isolates should be assessed carefully.