REPORT OF A CASE
A 68-year-old woman had an 8-year history of essential thrombocytosis and a recent pathologic fracture of her left femur secondary to a tumor composed of primitive megakaryoblasts ("granulocytic sarcoma") (Fig 1). She presented with a 2-day history of a spontaneous, rapidly progressive, painful lesion on the dorsum of her left hand.Physical examination revealed a 50-mm, domeshaped, purplish, hemorrhagic nodule. There was slight fluctuation of the center with marked edema and erythema of the surrounding skin (Fig 2).Aspiration cultures taken on hospital admission were negative. Significant laboratory data included the following values: hematocrit, 0.3; white blood cell count, 15.8 × 109/L, with 0.81 neutrophils; and platelet count, 225 × 109/L. Occasional blast cells were seen in the peripheral smear (Fig 3).A skin biopsy specimen of the nodule is shown in Fig 4.What is your diagnosis?
Acute febrile neutrophilic dermatosis