B107-04 Computed Tomography Findings and Clinical Outcomes in Nontuberculous Mycobacterial Pulmonary Disease (NTM-PD): A Systematic Review

Literature provides fragmented and heterogeneous descriptions of chest CT findings associated with NTM species. To date, no systematic review has synthesized evidence on the clinical role of CT in NTM-PD, including its capability to predict disease progression or treatment response. We report an initial summary of a systematic review with the goal of aggregating data to support evidence-based clinical decision-making and guidelines. Methods This review categorized studies based on two goals: 1) evaluating the diagnostic accuracy of CT findings, and 2) assessing their prognostic or predictive value. We performed a search using a unified algorithm across four major databases, combining MeSH terms and free-text keywords. The search targeted original research articles that addressed CT scans and NTM pulmonary infection or disease, excluding case reports and narrative reviews to maximize sensitivity. After duplicate exclusion, two review authors independently screened titles and abstracts and identified eligible studies. The disagreement was resolved through discussion with a third reviewer. For studies evaluating diagnostic accuracy, validity estimates will be calculated, and for prognostic/predictive data, from relevant clinical outcomes will be pooled. Results Of 2,220 articles identified (310 from MEDLINE, 424 from Scopus, 1,094 from EMBASE, 346 from Web of Science, and 46 via snowballing), 578 duplicates were removed, leaving 1,642 unique articles screened by title and abstract. After excluding 1,446 that did not meet the inclusion criteria, 196 studies were selected for full-text review. Two key aspects emerge when reviewing the evidence on the clinical role of chest CT for NTM-PD: 1) several diagnostic studies have evaluated chest CT findings to discriminate NTM infections from other conditions, such as TB, in patients with cystic fibrosis (CF) and non-CF bronchiectasis; 2) chest CT findings are increasingly used to predict clinical outcomes, including late disease progression, culture conversion in treated patients, and mortality. CT features such as cavities, bronchiectasis, nodules, and consolidation are included in scoring systems to assess disease severity and monitor patients’ clinical progress. However, variation in baseline population characteristics, such as the reason for scans (NTM-PD clinical suspicion vs. incidental findings) or the differential diagnosis based on CT results (NTM-PD vs. TB), limits the pooled validity estimates. Differences in comparison groups, CT feature definitions, and model covariates also complicate the synthesis of prognostic data. Conclusions This review offers comprehensive data and findings on the state-of-the-art in diagnostic accuracy (NTM vs. TB) and predictive value of CT for NTM-PD, guiding future research priorities and informing evidence-based guidelines This abstract is funded by: Insmed