Research Clinical Analysis and Risk Factors Associated With a Poor Prognosis in Nontuberculous Mycobacterial Infection: An 8-year Retrospective Cohort Study

Abstract Background: In recent years, the incidence of Nontuberculous mycobacteria (NTM) disease has been increasing worldwide. This study aimed to identify risk factors affecting the prognosis and mortality of non-HIV NTM patients. Methods: This retrospective study was conducted at Peking Union Medical College Hospital. The electronic medical records in the hospital’s database from January 2013 to December 2022 were retrospectively reviewed. Relevant data, including clinical characteristics, laboratory findings, detected microorganisms, treatments, and outcomes were collected and subjected to statistical analyses. Results: The search identified 745 patients diagnosed with NTM infection, of whom 147 met the inclusion criteria. Pulmonary NTM was most commonly observed (n=93; 63.3%), followed by disseminated infection (n=43; 29.3%). The most frequent NTM species was Mycobacterium avium complex (55.8%), followed by Mycobacterium abscessus (21.2%). The incidence of Aspergillus and Pseudomonas aeruginosa infection was significantly higher in the pulmonary NTM group than in the disseminated NTM group. Cumulative mortality in the total patients was 24.49% at 5 years. High charlson comorbidity index (CCI), high neutrophil-to-lymphocyte-ratio (NLR), hematological disease, and disseminated infection were identified as independent predictors of unfavorable outcomes. The area under the curve (AUC) values for NLR and NMLR were 0.751 and 0.763 with optimal cut-off values of 9.50 and 3.83, respectively, for prediction of mortality in NTM patients. Conclusions: High CCI, high NLR, hematological disease, and disseminated infection were identified as independent predictors of mortality in non-HIV NTM patients.