Molecular epidemiology and distribution of Cryptococcus neoformans in human immunodeficiency-positive patients in China.

Objective: This study aims to inform the prevention and treatment of Cryptococcus neoformans infections in China by analyzing the molecular epidemiology and distribution patterns of the pathogen.

Methods: A cross-sectional study was conducted involving a retrospective analysis of 64 clinical strains of Cryptococcus isolated from January 2018 to April 2023 across various domestic regions. Patient information was collected from human immunodeficiency virus-positive individuals in multiple hospitals located in 19 cities within China's southeastern coastal and southwestern regions. A VITEK MS mass spectrometer was employed for strain identification. Variants and mating types were amplified using polymerase chain reaction (PCR), while PCR multilocus sequence typing (MLST) was utilized for molecular genetic analysis of the strains. Evolutionary trees were constructed using MEGA software.

Results: The study identified a male predominance (2.37:1) among the 64 strains, with a median patient age of 38.5 years. Most strains (79.69%) were isolated from cerebrospinal fluid. All strains belonged to the Aα, VN I type, with MLST revealing three sequence types: ST5 (89.06%), ST32 (7.81%), and ST186 (3.13%).

Conclusion: From 2018 to 2023, Cryptococcus neoformans infections in China were predominantly found in middle-aged men, and the VN I genotype was the most common among the isolated strains.