A case series of co-infection in Mycobacterium tuberculosis and other pathogens: insights from nanopore sequencing

Background Tuberculosis (TB) continues to be a major global health burden, and co-infection with other pathogens further complicates the diagnosis and treatment of this infectious disease. The present retrospective study aimed to evaluate the clinical utility of nanopore sequencing in identifying co-infection caused by Mycobacterium tuberculosis (M.tb) and other pathogens. Methods Patients with M.tb co-infection from December 2021 to March 2023 at the Jiangxi Provincial Chest Hospital were retrospectively studied. Data were collected including demographics, symptoms, imaging findings, pathogen diagnosis tests, and treatment history. Pathogen tests involved culture, AFB smear, Xpert MTB/RIF, and nanopore sequencing. Results The enrolled patients included 20 M.tb cases and three nontuberculous mycobacteria (NTM) cases co-infected with other pathogens. Common clinical symptoms included cough (47.83%), expectoration (34.78%), and asthma (17.39%). Radiological examinations showed typical features of pulmonary tuberculosis, including nodules (73.91%), cord-like shadows (34.78%), cavities (34.78%), and destroyed lung manifestations (17.39%). Nanopore sequencing identified M.tb in a significant majority of the cases (86.96%), outperforming traditional culture tests (39.13%), acid-fast bacilli (AFB) tests (27.27%), and Xpert MTB/RIF (53.84%) tests. Notably, nanopore sequencing revealed that M.tb was frequently co-infected with Candida albicans, Klebsiella pneumoniae, and Mycobacterium abscessus. Three specific cases of co-infection with distinct diagnosis and treatment characteristics were presented in detail. They illustrated the complexity of TB co-infection management and the potential of nanopore sequencing for accurate diagnosis and informing the tailored therapeutic approaches. Conclusion Nanopore sequencing-based metagenomics method can help clinicians to identify TB co-infection patterns and formulate a rational drug regimen in time.