Diagnosis and treatment of infections caused by rapidly growing mycobacteria

Rapidly growing mycobacteria (RGM) are ubiquitous environmental organisms capable of causing a wide variety of infections in humans. The prevalence of RGM infections appears to be increasing, although exact incidence rates are unknown. Although some risk factors for pulmonary RGM infection have been determined, the specific host factors predisposing to disease in the majority of cases are not clear. Significant advances in molecular methods of mycobacterial identification have led to isolation of more varieties, changes in taxonomy, and more rapid and accurate diagnosis of RGM from clinical isolates. Despite significant advances in the field, diagnosing and treating RGM pulmonary infections remain complicated. Current guidelines are based on the most commonly encountered NTM. Their applicability to less frequent RGM isolates has not been definitively established. Treatment often requires multiple antimicrobial agents for prolonged periods of time, with varying degrees of success and significant associated morbidity.