DERMATITIS ASSOCIATED WITH COINFECTION OF NOTOEDRES SP., OTODECTES SP., AND MALASSEZIA SPP. WITH CONCURRENT TOXOCARA SPP. INFECTION IN A DOMESTIC CAT

Abstract

Dermatitis in cats is a skin disease that frequently involves multiple causative agents, complicating the diagnostic and clinical management processes. This case involves a co-infection with Notoedres sp., Otodectes sp., Malassezia spp., and Toxocara spp., requiring a comprehensive diagnostic approach and multimodal therapy. This case report describes a comprehensive diagnostic approach and evaluates the success of multimodal therapy in a domestic cat presenting with dermatitis due to multiparasitic co-infection. Diagnosis was established based on anamnesis, physical examination, complete blood count (CBC), superficial skin scraping, cytology using the acetate tape preparation (ATP) method, native and cytological otic swabs, trichogram, and native fecal examinations. The results revealed an infestation of Notoedres sp. and Otodectes sp., excessive proliferation of Malassezia spp., and the presence of Toxocara spp. eggs. The CBC showed leukocytosis dominated by lymphocytosis, macrocytic hypochromic anemia, and thrombocytopenia, while the trichogram demonstrated hair shaft damage characterized by irregular fractures, cuticle abrasion, and disrupted medullary continuity associated with severe pruritus. Clinical management was performed using a combination of topical selamectin sarolaner, amoxicillin clavulanic acid, diphenhydramine HCl, chlorpheniramine maleate, pyrantel pamoate-praziquantel, ketoconazole chlorhexidine shampoo, and fish oil supplementation. Clinical improvement became evident after 6 days of treatment and continued until day 9, the final day of evaluation, as indicated by reduced pruritus scores, resolution of crusts and excoriations, and new hair growth in the treated area. A comprehensive diagnostic approach coupled with multimodal therapy was effective in managing complex dermatitis due to multiparasitic co-infection in cats. A thorough diagnostic workup is highly recommended in chronic dermatitis cases to support an accurate diagnosis and the selection of appropriate therapy.