Atypical case of recurrent otitis with polyp formation in the ear canal associated with lagochilascariasis in a domestic feline in Brazil.

Lagochilascariasis is a neglected zoonosis that affects domestic and wild mammals, including humans, and can form nodules, especially on the neck. Although emerging, it is considered a rare disease in the Americas and, therefore, the objective was to report an atypical case of recurrent otitis with the formation of polyps in the ear canal in a domestic feline associated with lagochilascariasis in Brazil. A cat had a purulent exudate in one of her ears and responded poorly to treatments. During an otoendoscopy procedure, a polyp and nematodes were removed and sent for histopathological and parasitological diagnosis. Nematodes were subjected to DNA extraction, whose amplification of the 18S, cox1 and 12S genes in the Polymerase Chain Reaction (PCR) and genetic sequencing confirmed the presence of Lagochilascaris minor. To our knowledge, this is the first description of recurrent otitis with the formation of polyps in the ear canal associated with lagochilascariasis in domestic cats and the description of this atypical case may contribute to the elucidation of new clinical cases. Additionally, new molecular sequences are provided, contributing to the knowledge of the parasite.