Prominent hair follicle epithelial mucinosis in a cat with eosinophilic plaque

The feline eosinophilic granuloma complex is a well‐known dermatological problem that affects domestic cats. It has three characteristic components: eosinophilic plaque, eosinophilic granuloma and indolent ulcer. In this case report, we report a 5‐year‐old, mixed‐breed cat with pruritic plaque formation, which was typical for eosinophilic plaque by dermatological examination. The diagnosis was established by histopathological and clinical findings. As previous literature showed, hair follicle epithelium mucinosis as a histopathological finding could potentially give us fundamental clues about the microscopic diagnosis of this complex. We discuss the presentation, histopathology and treatment response in detail. This case highlights how intricate feline eosinophilic granuloma complex can be, and underscores the significance of hair follicle epithelium mucinosis as a diagnostic tool in histopathology.