Molecular identification of mycobacterial infections in nonsputum specimens

Abstract

Background: Mycobacterial infections can manifest in various anatomical sites, necessitating the analysis of nonsputum specimens for accurate diagnosis. The aim of this study was to identify the molecular cases of mycobacterial infections in nonsputum specimens using polymerase chain reaction based assays and gene sequencing methods. Methods: This observational study examined 161 nonsputum samples that have been stored in the Clinical Microbiology Laboratory at Hasanuddin University Hospital. Samples were analyzed by microscopy and molecular detection methods according to the standard methods at the Clinical Microbiology Laboratory of Hasanuddin University. Descriptive statistics were utilized to summarize patient demographics, infection characteristics, and outcomes. Results: The samples were collected from patients with an average age of 39.82 years. The anatomical sites of specimen collection varied, with musculoskeletal organs and eyes being the most common. Microbiological analysis revealed a predominance of Gram positive bacteria, with polymicrobial morphology observed. Methicillin susceptible Staphylococcus aureus were the most frequently isolated organisms. Acid fast bacilli were detected in 8.1% of samples. Phylogenetic analysis, based on 16S rRNA gene sequencing, revealed similarities between the samples and known mycobacterial species, including Mycobacterium parmense, Mycobacterium lacus, and Mycobacterium dioxanotrophicus. Conclusions: The findings highlight the microbial diversity observed in these infections. The study advocates for comprehensive diagnostic evaluations and targeted testing strategies based on both clinical and laboratory findings. This knowledge can contribute to improved diagnostic accuracy and optimized treatment strategies for mycobacterial infections.

Keywords

• molecular assay
• mycobacteria
• nonsputum
• nontuberculous mycobacteria