Characteristics and outcome of warm autoimmune hemolytic anemia in adults: New insights based on a single-center experience with 60 patients.

Warm autoimmune hemolytic anemia (wAIHA) is a rare autoimmune disease with poorly known natural history and management remaining mainly empirical. To better describe the characteristics and outcome of wAIHA in adults, we performed a single-center cohort study of patients diagnosed with wAIIHA from 2001 to 2012 in our center. Sixty patients (50% women) were included, the mean age at the time of wAIHA onset was 54 ± 23 years. wAIHA was considered "primary" for 21 patients (35%) and was associated with an underlying disorder in 39 (65%), including mainly lymphoproliferative disorders and systemic lupus. All patients but two needed treatment and received corticosteroids, with an overall initial response rate of 87%. However, 63% of the patients were corticosteroid-dependent and 56% required at least one second-line treatment including mainly rituximab (n = 19). At the time of analysis, after a mean follow-up of 46 months, 28 patients (47%) were in remission and off treatment and 5 (8%) had died. The presence of an underlying lymphoproliferative disorder was associated with reduced response to corticosteroids and increased need for second-line therapy. In conclusion, in the last decade and compared to a previous series from our center, the rate of secondary wAIHA has increased and the use of rituximab has emerged as the preferred second-line treatment and corticosteroid-sparing strategy; the overall mortality has significantly decreased (8 vs. 18%).