Acute febrile neutrophilic dermatosis associated with JAK-2 positive myeloproliferative disorder.

We present a case of a 77-year-old man with a history of myeloproliferative disorder. He was admitted with a 2-week history of erythaema, swelling and significant pain of the right forearm following a mechanical fall at home, which had caused a skin laceration. During his admission, he developed ongoing intermittent fever and persistently elevated C reactive protein, and total white cell count. Initially, he was treated with antibiotics for suspected cellulitis. However, symptoms continued to progress, making a suitable management plan challenging. Wound swabs, blood cultures and viral PCR did not confirm infection. A punch biopsy of a skin lesion on the forearm was performed. The histology demonstrated a dense infiltrate of neutrophils and neutrophilic debris in keeping with acute febrile neutrophilic dermatosis (Sweet's syndrome). He was treated with oral steroids and after that he had a complete resolution of symptoms. However, he required a period of rehabilitation before returning home.