Treatment outcomes in Mycobacterium abscessus pulmonary disease: A systematic review

Introduction: Mycobacterium abscessus complex (MABC) is an emerging global threat due to its intrinsic and acquired resistance to many antibiotics, making treatment particularly challenging. This systematic review aimed to evaluate current treatment regimens and clinical outcomes in patients with MABC pulmonary disease. Methods: A comprehensive electronic search of PubMed, Embase and Cochrane databases was conducted for studies published between 1 January 2010 and 31 December 2024. A total of 28 studies met the inclusion criteria, comprising 24 retrospective chart reviews and 4 multicentre prospective studies. Results: Sputum culture conversion (SCC) was reported in 25 studies, with rates ranging from 29% to 77%. Radiographic improvement was observed in 33% to 54% of patients, while clinical improvement varied widely, ranging from 14% to 91%. Notably, infections caused by M. massiliense were consistently associated with superior clinical, radiologic, and microbiologic outcomes compared to M. abscessus. Although surgical intervention was reported in selected cases, it was associated with higher SCC rates and remains a definitive treatment option in refractory disease. The overall risk of bias across studies was moderate to high, largely due to the predominance of retrospective study designs and heterogeneity in treatment protocols and outcome measures. Conclusion: These findings underscore the suboptimal outcomes associated with current treatment strategies for MABC pulmonary disease. There is an urgent need for large-scale, multicentre prospective studies utilising standardised treatment outcome definitions and unified therapeutic regimens to improve patient care and clinical outcomes.