Infantile Pure Red Cell Aplasia Secondary to Deficiency of Adenosine Deaminase2 (DADA2) Syndrome-Time to Think Beyond Diamond Blackfan Anemia.

Abstract

Deficiency of adenosine deaminase 2 (DADA2) is a rare autosomal recessive disorder characterized by vasculopathy, immunodeficiency, and hematological abnormalities. Its presentation as infantile pure red cell aplasia (PRCA) often mimics Diamond Blackfan anemia (DBA), leading to diagnostic delays and suboptimal management. This study retrospectively analyzed nine cases of DADA2-related PRCA diagnosed over 5 years at a tertiary care hospital. All patients harbored homozygous ADA2 mutations, predominantly p.Ile93Thr, and presented with severe anemia and reticulocytopenia. Misdiagnosed initially as DBA, none responded to steroid therapy. Our findings emphasize the need for comprehensive genetic analysis in PRCA to distinguish DADA2 from DBA for appropriate treatment.