Caracterização clínico-epidemiológica, molecular e susceptibilidade in vitro aos antifúngicos de isolados clínicos do complexo Cryptococcus neoformans / Cryptococcus gattii em Cuiabá e Várzea Grande - MT

Abstract

Cryptococcosis is a systemic fungal infection caused by the Cryptococcus species complex, the most commonly isolated species are Cryptococcus neoformans (serotypes A, D and AD) and Cryptococcus gattii (serotypes B and C). are those most frequently affected by C. neoformans serotype A and D. This species are distributed worldwide and is considered an important cause of morbidity and mortality in these patients. Cryptococcus gattii predominantly affects healthy individuals and rarely been reported affecting HIV positive individuals. It occurs endemically in northeastern Brazil. The purpose of this study was to characterize phenotypic and molecular characterization of the Cryptococcus species complex in clinical isolates of HIV-positive and HIV-negative patients attended at the Cuiabá emergency and Várzea Grande University Hospitals of the municipalities of Cuiabá and Várzea Grande, Mato Grosso, and determine the antifungal drug in vitro susceptibility profile. The study was conducted between September 2005 and February 2014. 62 clinical samples of Cryptococcus spp were identified by chemotyping using canavanine-glycine-bromothymol blue agar and confirmed by PCR. The molecular typing was performed by URA5 – RFLP. The susceptibility profile was performed using the reference broth microdilution method, in accordance with CLSI standards guidelines. Among the 62 patients with cryptococcosis, 40 (64,52%) HIV-positive individuals and 22 (35,48%) were found HIV negative. Considering gender, 36 were male and 26 females and the age ranged 4-74 years with a mean of 37.89 years. Clinical isolates, 44 Cryptococcus neoformans VNI, 17 Cryptococcus gattii VGII and one Cryptococcus neoformans VNII. Neurocryptococcosis was predominant clinical manifestation. Among these cases, the most frequent symptoms were headache, fever, vomiting, altered consciousness, and in some cases pulmonary involvement. The in vitro susceptibility was performed for 60 clinical isolates. The 60 isolates C. neoformans and C. gattii showed in vitro susceptibility to the antifungal agents tested. The ranges of minimal inhibitory concentrations (MIC) expressed in µg/mL for C. neoformans VNI were: amphotericin B (0.5 to 1.0), flucytosine (0.5 - 16), fluconazole (0.5 - 16), itraconazole (0.015 – 0.25), and voriconazole (0.03 to 0.25) and C. gattii VGII amphotericin B (0.5 - 1), flucytosine (1-16), fluconazole (1-16), itraconazole (0.03 - 0.5) and voriconazole (0.06 to 0.5).The genotype C. neoformans VNI was predominant in patients with AIDS, and C. gattii VGII was predominant in HIV negative patients. There were no cases of in vitro resistance of these genotypes to the antifungal agents tested. This was the first study reporting molecular, clinical and epidemiological aspects of clinical isolates of the Crytpococcus spp highlighting new features on molecular epidemiology in the State of Mato Grosso.