| Sumario: | Introduction: Cryptococcus neoformans and Cryptococcus gattii are the major causative agents of human cryptococcosis. Cryptococcosis recognized as an acute, subacute or chronic infectious mycotic zoonosis of world-wide significance and have a wide range of appearances such as meningitis, meningoencephalitis, pneumonia, osteomyelitis, abscesses in various internal organs and ocular disorders. Meningitis is the most frequent manifestation of cryptococcosis. The aims of this comprehensive study were to determine the molecular types of clinical Cryptococcus neoformans isolates by URA5-RFLP; to survey for the presence of the two mating types: a and a; and to determine the antifungal susceptibility profile of the clinical isolates. Materials and Methods: 220 clinical samples from 212 patients with suspected cryptococcosis were collected from April 2016 to June 2018. The clinical specimens included: cerebrospinal fluid (CSF), broncho alveolar lavage (BAL), spinal cord abscess, aspirated vesicles, sputum, brain biopsy and paraffin block of brain abscess. PCR-RFLP of the URA5 gene, mating type determination, in vitro susceptibility test to antifungal drugs alone and in combination (checkerboard technique) were performed. Result: out of 220 samples, 14 samples were positive. The prevalence of cryptococcosis was 5.7% (12/220) and all patients affected to meningitis. The most prevalent molecular type was VNI (85.7%) followed by VNII (14.3%). The lowest MIC values ranged from 0.031 - 0.125µg/ml) were observed for voriconazole. The checkerboard methods of antifungal combinations of amphotericin B with 5- fluorocytosine revealed synergistic interaction against 6 (43%) isolates, indifferent interactions against 8 (57%) isolates. The combination amphotericin B and fluconazole resulted synergistic interaction against 4 (28.5%) isolates, antagonism against 3(21.5%) isolates and indifferent against 7(50%) isolates. The combination of 5-FC with fluconazole yielded synergistic interaction against 3 (21.5%) isolates and indifferent 11(78.5%) isolates. Conclusion: The majority of the isolates, 87.5% (n=12), were VNI (var. grubii, serotype A), which accords with the fact that this variety causes most human cryptococcal infections worldwide.
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