P‐55 Febrile neutrophilic dermatosis in a miniature schnauzer resembling Sweet's syndrome in humans

Abstract

Sweet's syndrome is a human skin disease characterized by a rapid onset of painful erythematous plaques accompanied by fever. The disease usually occurs in middle‐aged women, and lesions are identified on the face, neck, chest and extremities after a nonspecific infection of the respiratory or gastrointestinal tract. Our case was a 6‐year‐old, spayed female miniature schnauzer. The dog presented with signs of fever, poor appetite, and lameness in the left‐front limb including the raising of the limb in question. Haematological and radiographic examinations revealed no abnormalities at presentation. Three days after presentation, ulceration in the oral cavity, oedema on the neck, and erythematous plaques on the groin, head, and pinnae were noted. Histopathology of the skin revealed perivascular infiltration of neutrophils and prominent oedema of the upper dermis. Dermatitis at the dermo‐epidermal interface was not observed. A test for antinuclear antibody was negative. The dog responded well to prednisolone treatment, and signs were alleviated. To diagnose Sweet's syndrome in humans, the patient is required to fulfil both major criteria and two out of four minor criteria. This dog was considered to have fulfilled such criteria in consideration of eruptions, histopathologic findings, fever and positive response to prednisolone. Bearing in mind that this was a middle‐aged female dog with an underlying autoimmune disease, and that immune‐mediated haemolytic anaemia, idiopathic thrombocytopenia, uveitis and arthritis were subsequently observed, this dog could be compared to Sweet's syndrome in humans. Funding: Self‐funded.