Acquired féline hair shaft abnormality resembling trichorrhexis nodosa in humans

A 2-year-old castrated male domestic short-haired cat presented with self-induced alopecia associated with whitish nodes on the remaining hair shafts. Light and scanning microscopy demonstrated swellings of the hair shafts, accompanied by cuticular damage leading to hair fractures with a typical brush-like appearance. A díagnosis of trichorrhexis nodosa associated with flea allergy dermatitis was made. Complete resolution of the condition with...