Skin Nodules in a 16-Year-Old Adolescent with Acute Lymphoblastic Leukemia

Abstract

A 16-year-old girl with B-lineage acute lymphoblastic leukemia was hospitalized for management of fever and neutropenia. She was empirically treated with intravenous vancomycin and ceftazidime. Her fever persisted, and on the seventh day of hospitalization, she developed a painful generalized erythematous rash. There was no history of trauma, infectious contacts, travel, gardening or pet exposures. On physical examination, she was febrile (39.2°C), but appeared well with no apparent distress. A skin examination revealed a rash that consisted of numerous violaceous papules, nodules and plaques on her trunk, abdomen and lower extremities. The lesions were surrounded by a 1 cm area of cellulitis, and some had necrotic centres (Figure 1). Otolaryngological evaluation revealed a necrotic nasal septum. Her abdominal examination was significant for hepatosplenomegaly. The rest of the examination was unremarkable. Figure 1) Skin lesion on thigh Laboratory data were significant for a white blood cell count of 0.4×109/L, hemoglobin level of 84 g/L and a platelet count of 21×109/L. Renal function and liver enzymes were normal; blood and urine cultures were negative for bacteria and fungi. A computed tomography scan of the chest with contrast revealed bilateral pulmonary nodules. A cutaneous punch biopsy was performed, and specimens were submitted for culture and histopathology (Figures 2 and ​and33). Figure 2) Deep reticular dermis. Gomori methenamine silver stain, original magnification ×10 Figure 3) High power view of periodic acid-Schiff stain What is the diagnosis?