Notoedric Mange

Notoedric mange is a nonseasonal, transmissible, pruritic dermatosis of cats caused by Notoedres cati. It can cause transient lesions on most mammals, including dogs and humans. All in-contact cats, especially littermates, are more or less affected.

The medial borders of both pinnae are affected first, then the whole pinna is affected; the lesions then spread all over the face, eyelids, neck, and, infrequently, the perineum and feet. Generalization is unusual. Papules are early transient lesions. The skin rapidly becomes thickened and forms large wrinkles covered with thick, adherent, yellowish to silvery crusts. Pruritus is intense and results in alope­cia. Severe excoriation leads to infected wounds. Lymphadenopathy is a common feature.

Differential diagnosis includes otodectic dermatitis, cheyletiellosis, food allergy, atopic dermatitis, contact dermatitis, and pemphigus foliaceus or erythematosus. Mites are more readily found on skin scrapings than Sarcoptes scabiei. Nevertheless, due to their small size, the scraping should be scrutinized under 10 ? objective, closed diaphragm, medium light, and after good clearing of the sample.

Many acaricidal drugs are toxic in cats, particularly organochlorates, organophos­phates, permethrin, and amitraz. Avermectins (selamectin, ivermectin) and lime sulfur are effective.

Treatment of the premises is mandatory because the mite can survive for more than 2 weeks in the environment.⁵