Nontuberculous mycobacteria.
The nontuberculous mycobacteria are for the most part ubiquitous environmental organisms that only rarely cause disease in humans. Therefore, the normal host defense against these organisms must be quite robust, as exposure is universal and disease is rare. The organisms that are most commonly encountered in clinical practice, Mycobacterium avium, M. intracellulare, M. kansasii, M. fortuitum, M. abscessus, and M. chelonae, are frequently found in water sources and soil. These organisms share significant structural and biochemical similarities with their more pathogenic relative, M. tuberculosis (MTB). Because they are of significantly lower pathogenicity than MTB, patients with abnormal susceptibility to these infections should include those with defects that may be identifiable. Study of these patients should lead to determination of the mechanisms underlying resistance to these organisms, which in turn are likely to be highly informative regarding host defense against these infections and their more virulent relative MTB. Furthermore, recognition of host factors that permit infection with nontuberculous mycobacteria in otherwise normal hosts will identify pathways that can be targeted for therapeutic intervention. Thus, the search for genetic and acquired susceptibility to nontuberculous mycobacteria is also a search for susceptibility factors for MTB as well as an opportunity to recognize endogenous pathways that can be exploited therapeutically.
Holland
S M
SM
Laboratory of Host Defenses, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892-1886, USA. smh@nih.gov
D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D004359:Drug Therapy, Combination / Q000627:therapeutic use; D006801:Humans; D008171:Lung Diseases / Q000382:microbiology* / Q000503:physiopathology; D009164:Mycobacterium Infections / Q000175:diagnosis / Q000188:drug therapy / Q000453:epidemiology / Q000503:physiopathology*; D009165:Mycobacterium Infections, Nontuberculous / Q000175:diagnosis / Q000188:drug therapy / Q000453:epidemiology / Q000503:physiopathology*
D000900:Anti-Bacterial Agents