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

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) and (GTG) 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) and (GTG) , 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.

Disseminated cryptococcosis in a HIV-negative patient: Case report of a newly diagnosed hypertensive adult presenting with hemiparesis

“…Different geographical locations can contribute to the epidemiological differences observed. This is further supported by the report of C. deutrogattii in Ivory Coast of which the isolate was susceptible to fluconazole [15]. To our knowledge, this case is only be the second in Africa and the first in East Africa [16], highlighting the possible underreporting of C. deuterogattii cases in Africa due to limited molecular diagnostics.…”

Cryptococcus genetic diversity and mixed infections in Ivorian HIV patients: A follow up study

“…One patient was resampled in the 26 th week following a relapse. For each patient, the entire culture and five isolates of Cryptococcus were recovered as previously described [29–31, 33]. Phenotypic characterization of the Cryptococcus species was achieved by chemotyping in L-canavanine-glycine-bromothymol blue (CGB) agar.…”

“…gattii species complexes from clinical sources in Yaoundé, Cameroon and Abidjan, and Ivory Coast and showed that C . neoformans (A, AFLP1/VNI) is widespread in the environment and is associated with the majority of cases of cryptococcosis in Ivory Coast [29–31]. During these studies, the authors demonstrated that some patients suffered concurrent infections by different sero-genotypes, including mixed infections by two different Cryptococcus species, C .…”

“…neoformans AFLP1/VNI and C . deuterogattii AFLP6/VGII [29]. Thus, the possibility of mixed infection must be considered for the management of cryptococcosis.…”

Ecoepidemiology of Cryptococcus gattii in Developing Countries

“…Congo [ 32 ], and South Africa [ 56 ]. The species C. deuterogattii (genotype AFLP6/VGII) was reported causing cryptococcosis in HIV-positive patients from Ivory Coast [ 59 ]. In addition, C. tetragattii (genotype AFLP7/VGIV) was found to be a major cause of meningitis in HIV-positive patients in Zimbabwe [ 57 , 58 ] and was reported to cause cryptococcosis in patients from Botswana, Malawi, and South Africa [ 57 , 60 ].…”