Caracterização clínica, cito-histomorfológica e molecular da esporotricose felina na Ilha de São Luís-MA

Abstract

Sporotrichosis is a zoonotic cutaneous mycosis caused by saprophytic fungi of the genus Sporothrix spp. which affects cats, armadillos, horses, dogs and humans. In urban areas, cats are the main transmitters of the disease to humans, through bites and scratches. The clinical forms of the disease are: fixed cutaneous, disseminated cutaneous, extracutaneous and lymphocutaneous. The aim of this study was to carry out the clinical, phenotypic and molecular characterization of sporotrichosis in cats living on the island of São Luís, in the state of Maranhão. From October 2022 to July 2023, clinical assessments and cytological examinations were carried out on cats suspected of having sporotrichosis seen at the Francisco Edilberto Uchôa Lopes Veterinary Hospital of the State University of Maranhão. Felines with lesions suggestive of sporotrichosis were selected, without criteria of breed, sex, age or reproductive status. Exudate from the lesions was collected for fungal culture and cytological examination. The positive samples were isolated and sent for phenotypic and molecular identification of the fungal genus. A total of 46 animals were selected: 33 males and 13 females. The disseminated cutaneous clinical form was observed in 70% of the cats evaluated. The regions of the body with the most lesions were the face, ears, back of the thoracic region and limbs. In the fungal culture, white colonies were observed, which progressively became blackish and had a leathery texture compatible with the species Sporothrix spp. The micromorphological analysis showed hyaline hyphae with round conidia and daisy-like conidiophores. The samples that tested positive in the micromorphological evaluation were sent for molecular analysis. PCR was carried out using primers specific to the S. brasiliensis species. All 46 samples successfully amplified the CAL gene. Five samples were selected for phylogenetic analysis. The BLASTn analysis found isolates with percentages of genetic identity ranging from 90 to 100% with sequences of S. brasiliensis (cal gene), previously deposited in the genbank of isolates from different hosts and locations, such as felines, dogs and humans. S. brasiliensis is responsible for causing disease in felines living on the island of São Luís - MA.