Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2020 Mar;63(3):284-293.
doi: 10.1111/myc.13041. Epub 2020 Jan 13.

Genotypic diversity in clinical and environmental isolates of Cryptococcus neoformans from India using multilocus microsatellite and multilocus sequence typing

Anupam Prakash  1 , Gandhi Sundar  1 , Brijesh Sharma  2 , Ferry Hagen  3   4   5 , Jacques F Meis  6   7 , Anuradha Chowdhary  1
Affiliations

Genotypic diversity in clinical and environmental isolates of Cryptococcus neoformans from India using multilocus microsatellite and multilocus sequence typing

Anupam Prakash et al. Mycoses. 2020 Mar.

Abstract

Background: Cryptococcus neoformans is the leading cause of cryptococcal meningitis in HIV/AIDS patients. As infections in humans are predominantly caused by the inhalation of basidiospores from environmental sources, therefore, analysing the population structure of both clinical and environmental populations of C neoformans can increase our understanding of the molecular epidemiology of cryptococcosis.

Objective: To investigate the genotypic diversity and antifungal susceptibility profile of a large collection of C neoformans isolates (n = 523) from clinical and environmental sources in India between 2001 and 2014.

Materials and methods: Cryptococcus neoformans isolates were genotyped by AFLP, microsatellite typing (MLMT) and MLST. In vitro antifungal susceptibility for standard antifungals was undertaken using CLSI M27-A3.

Results: All isolates were C neoformans, AFLP1/VNI and exhibited mating-type MATα. MLMT revealed that the majority of isolates belonged to microsatellite cluster (MC) MC3 (49%), followed by MC1 (35%), and the remaining isolates fell in 11 other MC types. Interestingly, two-thirds of clinical isolates were genotype MC3 and only 17% of them were MC1, whereas majority of environmental strains were MC1 (54%) followed by MC3 (16%). Overall, MLST assigned 5 sequence types (STs) among all isolates and ST93 was the most common (n = 76.7%), which was equally distributed in both HIV-positive and HIV-negative patients. Geometric mean MICs revealed that isolates in MC1 were significantly less (P < .05) susceptible to amphotericin B, 5-flucytosine, itraconazole, posaconazole and isavuconazole than isolates in MC3.

Conclusions: The study shows a good correlation between MLMT and MLST genotyping methods. Further, environmental isolates were genetically more diverse than clinical isolates.

Keywords: Cryptococcus neoformans; AFST; India; MLMT; MLST; multilocus microsatellite typing.

PubMed Disclaimer

References

REFERENCES

    1. Kwon-Chung KJ, Fraser JA, Doering TL, et al. Cryptococcus neoformans and Cryptococcus gattii, the etiologic agents of cryptococcosis. Cold Spring Harb Perspect Med. 2014;4:a019760.
    1. UNAIDS. Report on the India AIDS Epidemic. [Online] Available at: https://www.unaids.org/en/regionscountries/countries/india.2017 Accessed on 02 November 2019.
    1. Rajasingham R, Smith RM, Park BJ, et al. Global burden of disease of HIV-associated cryptococcal meningitis: an updated analysis. Lancet Infect Dis. 2017;17:873-881.
    1. Maziarz EK, Perfect JR. Cryptococcosis. Infect Dis Clin North Am. 2016;30:179-206.
    1. Chowdhary A, Randhawa HS, Prakash A, Meis JF. Environmental prevalence of Cryptococcus neoformans and C gattii in India: an update. Crit Rev Microbiol. 2012;38:1-16.

MeSH terms

Substances

Associated data

LinkOut - more resources