CULTURE CONVERSION AND MORTALITY IN PATIENTS WITH MYCOBACTERIUM AVIUM COMPLEX LUNG DISEASE: A SYSTEMATIC REVIEW

Abstract

SESSION TITLE: Chest Infections Posters SESSION TYPE: Original Investigation Posters PRESENTED ON: October 18-21, 2020 PURPOSE: Patients with mycobacterium avium complex (MAC) lung disease are at risk for disease progression (Park 2017) and may have a higher risk of death (Diel 2017). We sought to examine microbiological treatment outcomes (culture conversion) and the potential association with mortality in patients with MAC lung disease through a systematic literature review. METHODS: We used the National Institute for Health and Clinical Excellence guidance for systematic reviews to search Embase, PubMed, relevant congress abstracts, and the Cochrane Library (data cutoff, November 8, 2019). English-language studies of MAC lung disease that reported mortality and/or microbiological outcomes were included. Prospective (controlled trials, observational studies) and retrospective (claims databases, registries) studies with ≥ 25 patients were included. A total of 3451 indexed records were screened by 2 independent reviewers. Data were extracted from relevant studies and expressed as population-weighted means. RESULTS: Mean all-cause mortality across 56 studies (population size, n = 26,287) was 31% (range, 1%-67%); mortality attributable to MAC lung disease was 4% (range, 0.3%-35%). Culture conversion rate across 88 studies (population size, n= 8531) was 56.5% (range, 0%-95%). There was broad variance in treatments across the studies that included variations in duration, regimen, and follow-up period (3 months to > 10 years). Treatment duration was often 12 to 24 months and ranged from 8 weeks to “up to 19 years.” A total of 38 studies (population size, n= 6455) reported both mortality and culture conversion. Across these studies, the relationship between decreased culture conversion and increased all-cause mortality was negligible (R2 = 0.04), while the correlation between MAC-attributable mortality and lack of culture conversion showed a weak trend (R2 = 0.30). CONCLUSIONS: This systematic review highlights inconsistency in treatment approaches for patients with MAC lung disease. Analysis of the literature found variable rates of all-cause mortality in patients with MAC lung disease, with only half of patients achieving culture conversion with treatment. A limited number of studies included both mortality and culture conversion outcomes; available indirect data suggest that MAC-attributable mortality tended to be lower in studies with overall higher culture conversion rates. Limitations include a small number of studies, and inconsistency in methods and outcomes definitions. CLINICAL IMPLICATIONS: Despite the availability of treatment guidelines in MAC lung disease, published studies highlight inconsistencies in the approach to treatment. A wide variation in treatment success (culture conversion) was found, which may be influenced by treatment approach and duration. Some data suggest improved mortality outcomes in studies with higher culture conversion rates, but more evidence is needed to demonstrate a survival benefit associated with culture conversion. DISCLOSURES: Employee relationship with Insmed Please note: >$100000 Added 02/25/2020 by Kristan Cline, source=Web Response, value=Salary Consultant relationship with Insmed Please note: $5001 - $20000 Added 04/15/2020 by Patrick Flume, source=Web Response, value=Consulting fee Research grants relationship with Insmed Please note: >$100000 Added 04/15/2020 by Patrick Flume, source=Web Response, value=Grant/Research Support Employee relationship with Insmed Please note: >$100000 Added 04/15/2020 by Zhanna Jumadilova, source=Web Response, value=Salary No relevant relationships Added 05/12/2020 by Kevin Mange, source=Web Response, value=Ownership interest Removed 05/12/2020 by Kevin Mange, source=Web Response No relevant relationships by Kevin Winthrop, source=Web Response