Molecular epidemiology and clinical characteristics of 34 cases of cryptococcal infection in HIV patients

Abstract

Abstract:

Objective To analyze the molecular epidemiology and clinical characteristics of cryptococcosis occurred in HIV-infected patients, and to provide evidence for the prevention and treatment of cryptococcosis. Methods A total of 34 Cryptococcus neoformans strains isolated from HIV-infected patients were collected and the general data of patients were investigated retrospectively. The isolates were first identified based on the matrix-assisted laser desorption/ionization time-of flight mass spectrometry (MALDI-TOF MS), the MICs of the five kinds of antifungal drugs were carried out according to ATB Fungus3. PCR with specific primers were used to identify variants and mating types. The clonal relatedness was characterized by multilocus sequence typing (MLST) analysis. Results Most Cryptococcus neoformans strains were isolated from middle-aged men and mainly came from cerebrospinal fluid (73.5%). Cerebrospinal fluid pressure was (27.26±11.52) mmH₂O on average,median CD4 T-cell count was 28 cells/μL (3~163 cells/μL), median CSF WBC count was 32 (2~110)×10⁶/L, the median protein was 362 mg/L (160~2 730 mg/L), median glucose 2.28 mmol/L (1.50~5.98 mmol/L). All strains were sensitive to five kinds of antifungal drugs and were identified as serotype A, mating type α and molecular type VNⅠ. MLST analysis divided the 34 isolates into two sequence types (STs), including ST5 (n=32), ST32 (n=1) and ST186 (n=1). Conclusion In recent two years, cryptococcosis occurred in HIV-infected patients were more common in middle-aged men. The laboratory tests lacked specificity. The resistance of Cryptococcus neoformans isolates from HIV-infected patients was not serious, ST5 is the main clonal.

Key words: Cryptococcus neoformans, HIV, molecular epidemiology, MLST

CLC Number:

R379.5

CHEN Yan-hui, YU Feng, BIAN Ze-yuan, HONG Jian-ming, ZHONG Qiao-shi, HANG Ya-ping, ZHANG Nan, HU Long-hua. Molecular epidemiology and clinical characteristics of 34 cases of cryptococcal infection in HIV patients[J]. Chinese Journal of Mycology, 2018, 13(3): 152-157.

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