Seemingly trivial lesion with devastating consequences

[摘要] Dear Editor, a 70-year-old man presented to the emergency department with pain in his right lower extremity. His relevant past medicalhistory included myelodysplastic syndrome (MDS), multilineage dysplasia subtype, initially categorized as low risk (International Prognostic Scoring System Revised version). Active treatment was notindicated. During a follow-up consultation 4 years later, myeloblastswere described for the first time in peripheral blood (<5%) withhemoglobin (Hb) of 12 g/dl, a white blood count (WBC) of 7 × 103/µl,and a platelet count of 200 × 103/µl. A new bone marrow evaluationshowed grade 3 myelofibrosis. The treatment proposed was 75 mg/m2of subcutaneous azacitidine for 7 days, every 4 weeks. Twenty fourhours after finishing his first cycle, the patient presented with induration, erythema, and progressive pain in the right lower extremitycoinciding with the sites of subcutaneous administration. He developedfever ∼48 h after the last dose of azacitidine.