A case of presumed autoimmune subepidermal blistering dermatosis treated with oclacitinib.

BACKGROUND Autoimmune subepidermal blistering dermatoses (ASBD) are a group of severe autoimmune dermatoses rarely described in dogs. Their treatment usually necessitates the long term use of medications potentially associated with adverse effects. In humans, Janus Kinase (JAK) inhibitors have been demonstrated to be of value in some cases of autoimmune skin disease. HYPOTHESIS/OBJECTIVES To evaluate oral oclacitinib, a JAK-1 predominant inhibitor, in one case of ASBD in a dog. CASE REPORT A 5-year-old German shepherd cross-bred dog was presented with an acute onset of ulcerative and blistering skin lesions on the face, oral cavity, lateral trunk and limbs. Associated systemic signs were not seen. A clinical diagnosis of ASBD was supported by the finding of subepidermal clefts and visualization of the epidermal basement membrane zone at the bottom of the clefts on histopathological examination. Treatment was initiated with prednisolone at 1.2 mg/kg twice daily. Because of severe adverse effects and relapse, when the prednisolone dose was reduced, oclacitinib therapy was administered at 0.5 mg/kg twice a day. A complete resolution of clinical signs was noted after one month and no relapse was observed after twelve months of treatment. No adverse effects were reported. CONCLUSION The use of oclacitinib may be useful for the treatment of some autoimmune skin diseases in dogs. Further controlled studies are needed to confirm our findings.