Molecular Characterization and Azole Resistance Patterns of Candida Species Colonizing Sputum of Pulmonary Tuberculosis Patients in Mumbai, India

Background: Pulmonary tuberculosis (PTB) generates a compromised pulmonary environment that predisposes patients to opportunistic fungal colonization. While Candida albicans remains predominant, emerging non-albicans Candida species require molecular surveillance. Objective: We have to evaluate the prevalence, species distribution, molecular identity, and antifungal susceptibility profiles of Candida species isolated from sputum of PTB patients at a tertiary care center in Mumbai, India. Methods: A hospital-based cross-sectional study was conducted from June 2021 to December 2023. A total of 650 PTB sputum samples were processed successfully. Gram staining was used in phenotypic identification, KOH mount, germ tube testing, and chromogenic agar. Genotypic confirmation carried ITS region PCR amplification and Sanger sequencing with NCBI BLAST analysis. Antifungal susceptibility testing of Candida akabanensis isolates was performed by using the Semi-Solid Agar Antifungal Susceptibility (SAAS) screening method. Results: Candida was isolated from 192 of 650 specimens (29.54%). Among positive isolates, females comprised 61.46% and males 38.54%. Peak isolation occurred in the 28–37 years age group (31.77%). Species distribution: C. albicans 63.02%, Nakaseomyces glabratus 24.48%, C. akabanensis 11.46%, and C. tropicalis 1.04%. Among 22 C. akabanensis isolates, resistance rates were ketoconazole 68.18%, griseofulvin 59.09%, and fluconazole 45.45%, with 100% susceptibility to nystatin, itraconazole, and terbinafine. Conclusion: Considerable Candida co-colonization is present among PTB patients in Mumbai, including recovery of the uncommon species C. akabanensis. Be aware to routine mycological screening with molecular identification is recommended to guide appropriate antifungal selection. Clinical significance of colonization versus invasive infection requires further evaluation. Keywords: Pulmonary tuberculosis, Candida akabanensis, ITS sequencing, Antifungal susceptibility, Co-colonization, Mumbai