Mimicker of necrotising fasciitis with systemic inflammatory response syndrome: recurrent necrotising Sweet's syndrome associated with chronic myelogenous leukaemia.

A 73-year-old man presented with severe right upper quadrant abdominal pain, overlying erythema, hypotension and fever. CT scan revealed fasciitis and myositis of the right rectus abdominis muscle with subcutaneous inflammation involving the fasciae and muscle. Laboratory studies showed extreme leucocytosis. The combination of his symptoms, CT findings and laboratory results suggested necrotising fasciitis with systemic inflammatory response syndrome. Subsequent negative cultures on skin and muscle biopsy led to a diagnosis of necrotising neutrophilic panniculitis. Recurrent episodes of fever, and abdominal and buttocks pain at various sites, suggested an underlying haematological condition. Bone marrow biopsy and genetic analysis revealed chronic myelogenous leukaemia. The patient's symptoms of Sweet's syndrome resolved with glucocorticoid treatment and did not recur after starting treatment with a tyrosine kinase inhibitor.