Molecular epidemiology reveals genetic diversity among 363 isolates of the Cryptococcus neoformans and Cryptococcus gattii species complex in 61 Ivorian HIV-positive patients

Mycoses. 2016 Dec;59(12):811-817. doi: 10.1111/myc.12539. Epub 2016 Jul 27.

Abstract

Cryptococcal meningitis is a severe opportunistic infection in HIV-infected patients. In Ivory Coast, despite the availability of antiretroviral treatment (ART), this infection is still prevalent. The study investigates the genetic diversity of 363 clinical isolates of Cryptococcus from 61 Ivorian HIV-positive patients, the occurrence of mixed infections and the in vitro antifungal susceptibility of the isolates. Serotyping was performed via LAC1 and CAP64 gene amplification. Genotyping was performed using the phage M13 core (GACA)4 and (GTG)5 primers and restriction fragment length polymorphism analysis of the URA5 gene. By PCR fingerprinting, the presence of the three serotypes were demonstrated among the 363 isolates in the population studied: A (n=318; 87.6%), AD (n=40; 11%) and B (n=4; 1.1%). Using PCR fingerprinting with primers M13 (GACA)4 and (GTG)5 , we grouped the isolates into 56 molecular subtypes. We observed a high frequency (39.3%) of mixed infections, with up to two different genotypes per sample. None of the isolates were resistant to amphotericin B. Only 0.3% and 1.1% of the isolates were resistant to fluconazole and flucytosine respectively. This study revealed the high genetic diversity among Cryptococcus isolates, the occurrence of mixed infections and a high antifungal susceptibility for the majority of Ivorian cryptococcal isolates.

Keywords: antifungal susceptibility; cryptococcosis; genetic diversity; genotyping; mixed infection.

MeSH terms

  • AIDS-Related Opportunistic Infections / drug therapy
  • AIDS-Related Opportunistic Infections / epidemiology
  • AIDS-Related Opportunistic Infections / microbiology*
  • Adult
  • Amphotericin B / administration & dosage
  • Antifungal Agents / administration & dosage
  • Cote d'Ivoire / epidemiology
  • Cryptococcosis / drug therapy
  • Cryptococcosis / epidemiology
  • Cryptococcosis / microbiology*
  • Cryptococcus gattii / classification
  • Cryptococcus gattii / drug effects
  • Cryptococcus gattii / genetics*
  • Cryptococcus gattii / isolation & purification
  • Cryptococcus neoformans / classification
  • Cryptococcus neoformans / drug effects
  • Cryptococcus neoformans / genetics*
  • Cryptococcus neoformans / isolation & purification
  • Female
  • Genetic Variation
  • Humans
  • Male
  • Meningitis, Cryptococcal / drug therapy
  • Meningitis, Cryptococcal / epidemiology
  • Meningitis, Cryptococcal / microbiology*
  • Microbial Sensitivity Tests
  • Middle Aged
  • Molecular Epidemiology
  • Mycological Typing Techniques
  • Polymorphism, Restriction Fragment Length
  • Prospective Studies
  • Young Adult

Substances

  • Antifungal Agents
  • Amphotericin B