Epidemiology of Cryptococcus neoformans/C. gattii complexes in the northeast Argentina

CATTANA ME; FERNÁNDEZ M; TRACOGNA F; FORMOSA P; GIUSIANO G

Salvador de Bahía

Congreso; 17th Infocus and 1st ISHAM Latin American Congress; 2019

The aim of this study was to describe clinical and environmental isolates of Cryptococcus neoformans / Cryptococcus gattii complexes recovered during 2009-2014 from different cities of the northeast Argentina.A total of 139 isolates, 134 C. neoformans sensu lato and 5 C. gattii s.l. were included in this study. Forty-three environmental isolates (25 from pigeon droppings and 18 from trees) recovered in Resistencia and Corrientes cities and 96 clinical isolates from Resistencia, Corrientes and Formosa cities were studied. All the isolates were identified by phenotypic tests and genotyped by PCR-RFLP method (Meyer et al., 2003) at Instituto de Medicina Regional (Resistencia, Argentina). In addition, 58 isolates were studied by AFLP (Illnait-Zaragozí et al., 2012) and all C. gattii s.l. by MLST (Wieland Meyer et al., 2009) at Medical Microbiology & Infectious Diseases Dept., Canisius-Wilhelmina Hospital (Nijmegen, The Netherlands). One hundred and twenty-two isolates were identified as C. neoformans VNI/AFLP1 (40 by this method); 8 C. neoformans VNII/AFLP1B (8); 1 C. neoformans VNII/AFLP1A (VNB); 3 C. neoformans x C. deneoformans VNIII/AFLP3; 4 C. gattii VGI/AFLP4 and 1 clinical isolates of C. deuteorgattii VGII/AFLP6. In all cases molecular identification by AFLP and PCR-RFLP methods were coincident. The VNB isolate was found by AFLP due to better resolution of this technique. Table 1 show the identification and source of 139 isolates. In concordance with other authors, a high frequency of C. neoformans VNI genotype among both clinical (85.4%) and environmental (93%) isolates was observed. From pigeon droppings were recovered C. neoformans s. s. (VNI), and only one isolates of C. neoformans hybrid VNIII (VNI-VNII-VNIV). This concord with other author, where isolates different to VNI was found occasionally. This is the first report of C. neoformans VNB in Argentina.Six genotypes were identified in clinical isolates obtained from 70% HIV-positive patients, 25% with another risk factor and 5% immunocompetent. In this group, C. neoformans VNIII were hybrid VNII-VNIV. This hybrid was reported in 5% of isolates of Cryptococcosis Multicerter Study in Argentina. The MLST study showed that all C. gattii had the same genotype and they formed a clade phylogenetically separated from other isolates of the same genotype studied from other parts of the world. Two of them were isolates from immunocompromised patients and two from trees. Besides, the C. deuterogattii strain was recovered from an immunocompetent patient. This isolate was identical to the main genotype VGIIa from Vancouver (Canada) outbreak of 1999. The patient referred had never been outside the boundaries of Argentina. This find is concordant with the hypothesis of South American ancestor of the main genotype of the outbreak on Vancouver Island.