RESUMEN
RATIONALE: Plasma exchange is the principal treatment for acquired thrombotic thrombocytopenic purpura (TTP) but is invasive and may have adverse effects. Reports of immunoglobulin therapy for acquired TTP without plasma exchange are rare. PATIENT CONCERNS: A 14-year-old girl was admitted because of hemolytic anemia and thrombocytopenia. DIAGNOSIS: Acquired TTP was diagnosed based on low ADAMTS13 (a disintegrin-like and metalloproteinase with thrombospondin type 1 motif, 13) activity and a high ADAMTS13 inhibitor level. INTERVENTIONS & OUTCOMES: Fresh frozen plasma was initially effective. Prednisolone and immunoglobulin resolved the condition with no adverse effects and rendered plasma exchange unnecessary. LESSONS: Compared with biological agents, immunoglobulin is cost-effective, readily available, and has a proven long-term safety record, making it a possible treatment option for acquired thrombotic thrombocytopenic purpura.