CASE_STUDY Diffuse cutaneous mastocytosis was diagnosed in a 6-year-old, indoor, neutered female domestic European shorthair cat. Marked pruritus located mainly on the head and neck was noticed in the cat and in this area the animal had developed alopecia, crusts, and plaques. Histologically, monomorphic mast cells were found in the superficial dermis and around the hair follicles. Mast cells were well differentiated, with central nuclei and granular cytoplasm, with metachromatic granules which stained positively with Toluidine blue stain. The animal was successfully treated with oclacitinib at a dose of 1 mg/kg, twice a day per os. https://macvetrev.mk/Files/Article/2020/10.2478/macvetrev-2019-0025/macvetrev-2019-0025.pdf 2020-03-15T09:00:00 81 83 10.2478/macvetrev-2019-0025 dermatology mastocytosis oclacitinib cats Marcin Szczepanik kryll@poczta.onet.pl false 1 Sub-department of Clinical Diagnostics and Veterinary Dermatology, Faculty of Veterinary Medicine, University of Life Sciences in Lublin, Głęboka 30, 20-612 Lublin, Poland LEAD_AUTHOR Piotr Wilkołek false 2 Sub-department of Clinical Diagnostics and Veterinary Dermatology, Faculty of Veterinary Medicine, University of Life Sciences in Lublin, Głęboka 30, 20-612 Lublin, Poland AUTHOR Anna Śmiech false 3 Department of Pathology, University of Life Science in Lublin, 20-620 Lublin, Głęboka 30, Poland AUTHOR Iwona Taszkun false 4 Sub-department of Clinical Diagnostics and Veterinary Dermatology, Faculty of Veterinary Medicine, University of Life Sciences in Lublin, Głęboka 30, 20-612 Lublin, Poland AUTHOR Liska, W.D., MacEwen, EG., Zaki, F.A., Garvey, M. (1979). Feline systemic mastocytosis: A review and results of splenectomy in seven cases. J Am Anim Hosp Assoc. 15, 589-597. 1 10.1111/j.1752-1688.1979.tb00375.x Gross, T., Ihrke, P., Walder, E. (2005). Mast cell tumors. In: Skin diseases of the dog and cat: Clinical and histopathologic diagnosis. (pp. 853-865). Oxford: Blackwell Science. 2 10.1002/9780470752487 Brown, C.A., Chalmers, S.A. (1990). Diffuse cutaneous mastocytosis in a cat. Vet Pathol. 27, 366- 369. PMid:2238391 3 10.1177/030098589002700511 Tomich, L. M., Pieper, J. B. (2019). Urticaria pigmentosa-like skin disease in a domestic shorthair cat. J. Feline Med Surg Open Reports. 5(1): 1-4. PMid:30671254 PMCid:PMC6327337 4 10.1177/2055116918821197 Frank, R.K., Galvan, B.A., Schoell, A.R. (2014). Use of oclacitinib (Apoquel, Zoetis) for treatment of cutaneous mastocytosis in a cat. Vet Dermatol. 25, 153. 5 10.1111/vde.12131 Ngo, J, Morren, MA, Bodemer, C, Heimann, M, Fontaine, J. (2019). Feline maculopapular cutaneous mastocytosis: a retrospective study of 13 cases and proposal for a new classification. J Feline Med Surg. 21, 394- 404. PMid:29860905 6 10.1177/1098612X18776141 Colombo, S., Scarampella, F., Ordeix, L., Roccabianca, P. (2012). Dermatophytosis and papular eosinophilic/mastocytic dermatitis (urticaria pigmentosa-like dermatitis) in three Devon Rex cats. J Feline Med Surg. 14, 498-502. PMid:22736683 7 10.1177/1098612X12440761