Acute myeloid leukemia presenting as erythema nodosum A case report

Rationale: Erythema nodosum (EN), a type of septal panniculitis, could be a rare nonspecific cutaneous presentation of acute myeloid leukemia (AML). Patient Concerns: A 58-year-old Chinese female was admitted for a 4-week history of painful cutaneous lesions, accompanied by a sternal pain and fever. The lesions once resolved spontaneously but then recurred. Physical examination revealed warm, tender, indurated, rounded, erythematous to violaceous nodules in bilateral lower extremities, ranging in diameter from 1 to 6cm. Blood marrow examination was compatible with AML-M2. Diagnoses: AML-M2 presenting as EN. Interventions: Daunorubicin and cytarabine were used in induction chemotherapy. The patient achieved complete remission and her skin lesions disappeared simultaneously. Six courses of consolidation chemotherapy were conducted in the following 6 months. Outcomes: The patient died due to AML relapse. Lessons: The case strengthens the awareness of cutaneous involvement of AML and raises oncological vigilance in patients with EN.