Other Slow-Growing Nontuberculous Mycobacteria.

Area of Science:

• Microbiology
• Infectious Diseases
• Clinical Medicine

Background:

• Nontuberculous mycobacteria (NTM) are increasingly recognized as clinically significant pathogens.
• Previously considered contaminants, some NTM species are now known to cause localized or disseminated infections.
• NTM are ubiquitous in the environment, with infections typically acquired through inhalation or inoculation.

Purpose of the Study:

• To review the expanding list of clinically important slow-growing NTM.
• To discuss the classification, sources, and transmission of NTM.
• To outline current therapeutic strategies and treatment durations for NTM infections.

Main Methods:

• Literature review of NTM classification, epidemiology, and clinical management.
• Summary of in vitro susceptibility testing and recommended drug regimens.
• Discussion of treatment duration for immunocompetent and immunocompromised patients.

Main Results:

• The spectrum of pathogenic NTM is broadening, including previously overlooked species.
• Environmental exposure is the primary route of NTM infection; person-to-person transmission is not typical.
• Optimal treatment regimens and durations are not always established, necessitating individualized approaches based on susceptibility testing.

Conclusions:

• Effective management of NTM infections requires understanding species-specific characteristics and susceptibility patterns.
• Combination antibiotic therapy, often including clarithromycin, rifampin, and ethambutol, is frequently recommended.
• Treatment duration varies, typically 18–24 months for immunocompetent individuals and longer for immunocompromised patients, especially with disseminated disease.