Mycobacterium abscessus: challenges in diagnosis and treatment.

PURPOSE OF REVIEW: Mycobacterium abscessus is the most common rapidly growing mycobacterium that causes lung disease. This review describes recently published literature regarding M. abscessus taxonomy, environmental niche, diagnosis, management and outcome in pulmonary disease in adults and adolescents with cystic fibrosis.

RECENT FINDINGS: The classification of M. abscessus subsp. abscessus, M. abscessus subsp. massiliense and M. abscessus subsp. bolletii is useful clinically because of the discovery of the erm(41) gene, which is responsible for macrolide resistance in M. abscessus. Macrolide susceptibility is key for successful treatment of M. abscessus subsp. massiliense. The poor outcome and eradication of M. abscessus subsp. abscessus remains both a diagnostic and treatment challenge in approximately 80% of isolates that are macrolide resistant. Molecular studies, such as genotyping, may allow prediction of disease progression. Overall, there is a dearth of new literature surrounding M. abscessus.

SUMMARY: New studies differentiating M. abscessus subsp. abscessus and M. abscessus subsp. massiliense based on the erm(41) gene demonstrate the latter to have a better prognosis and improved treatment outcomes. M. abscessus subsp. abscessus remains a formidable pathogen in diagnosis and treatment.