An atypical presentation of Sweet's syndrome in a myelofibrosis patient

A 46-year-old man with no significant medical history presented to haematology with symptoms of fatigue, dyspnoea on exertion and weight loss. Physical examination revealed a lesion on the right shin and splenomegaly. Labs were significant for leucocytosis with immature components, thrombocytosis and 3% peripheral blasts on smear. A bone marrow biopsy confirmed a diagnosis of myelofibrosis (MF). Dynamic International Prognosis Scoring system was 2. He was started on ruxolitnib, with decitabine added subsequently prior to definitive therapy with an allogenic haematopoietic stem cell transplant. His course with decitabine was complicated with febrile neutropaenia with multiple tender erythematous plaques unresponsive to antibacterial and antifungal coverage. A skin biopsy showed neutrophilic dermatitis, consistent with a diagnosis of Sweet's syndrome (SS) and empirical treatment with glucocorticoids was initiated resulting in resolution of symptoms. This report reviews the literature for cases of SS in the setting of MF.