Characteristics and prognosis of mixed autoimmune hemolytic anemia: a retrospective study of 49 cases

Abstract

Abstract Mixed autoimmune hemolytic anemia (mAIHA) is a rare type of autoimmune hemolytic anemia (AIHA) with poorly known natural characteristics. We retrospectively analyzed the characteristics of patients with mAIHA from January 2010 to December 2021 in our center. 49 cases diagnosed with mAIHA were enrolled to be retrospectively analyzed. mAIHA accounted for 13.8% (49 cases) of all 356 AIHA patients. The initial hemoglobin levels of 34.7% patients were lower than 60 g/L. Nearly half (44.9%) mAIHAs were secondary and had lower C3 levels than that in primary group (P = 0.03). 71.1% mAIHA patients received second-line or even third-line therapy, and the overall response rate was 93.3%. 13 primary patients received glucocorticoids only, of which 46.2% got complete response and 53.8% partial response. 8 primary patients received low-dose rituximab with a respond rate of 87.5% (median time 4 weeks). In regards of complications, 35.6% patients developed infections and 8.9% thrombotic events. The relapse rate was 60%, and lower initial Hb levels (P = 0.044) and primary etiology (P < 0.001) were risk factors for relapse. The 5-year overall survival rate was 93.6%. Lung infection (χ2 = 6.109, P = 0.013) and age ≥ 60 years old (χ2 = 8.501, P = 0.004) had been responsible for death. In conclusion, mAIHA should be treated differently and especially concerned the etiology behind it. Attention should be put on the risk factors of recurrence and effective treatments still need to be further explored.