Mycobacterial infections in a large Virginia hospital, 2001-2009

BACKGROUND: In areas where both tuberculosis (TB) and nontuberculous mycobacteria (NTM) are prevalent, descriptive studies of the clinical features of individual mycobacteria are needed to inform clinical triage. METHODS: We queried the University of Virginia Clinical Data Repository for all mycobacterial infections from 2001-2009. RESULTS: Of 494 mycobacterial infections in 467 patients there were 22 species. Patients with pulmonary Tb were more likely to be reported as immigrants (p < 0.001) and less likely to have a predisposing risk factor for NTM (pre-existing lung disease or host predisposition; p = 0.002). Review of chest CT scans revealed that TB infection was more likely to exhibit cavities and pleural effusion than NTM infection (p < 0.05). Among NTM infections M. kansasii, M. xenopi, and M. fortuitum were more likely than MAC to have cavities. There were at least 83 patients that met criteria for NTM lung disease and these were caused by 9 species. M. abscessus infection was associated with cystic fibrosis and M. xenopi infection was associated with male gender. CONCLUSIONS: In our center mycobacterial infections were common and of diverse species. Immigrant status, cavities, and effusion were associated with TB vs. NTM.