Thrombotic microangiopathy–like acute kidney injury revealing a germline GATA1 mutation in a child with inherited cytopenia

Thrombotic microangiopathy (TMA) is characterized by microangiopathic hemolytic anemia, thrombocytopenia, and organ injury, most commonly acute kidney injury (AKI). It may occur as a primary complement‑mediated disorder or secondary to other diseases. Germline mutations in GATA1 cause X‑linked thrombocytopenia with or without dyserythropoietic anemia. We report an 8‑year‑old boy with long‑standing steroid‑dependent cytopenias and congenital anomalies who presented with severe infection, hemolysis, thrombocytopenia, and AKI requiring hemodialysis. Although the presentation fulfilled criteria for suspected TMA, ADAMTS13 activity, complement factor H levels, and anti-factor H antibodies were normal, excluding primary TMA. Whole‑exome sequencing identified a hemizygous pathogenic GATA1 variant (c.646C>T; p.Arg216Trp), establishing GATA1‑related dyserythropoietic anemia with thrombocytopenia. Renal function fully recovered following supportive therapy, immunomodulation, and dialysis discontinuation. This case underscores the importance of considering secondary TMA‑like syndromes in inherited marrow disorders and highlights the diagnostic value of genomic testing in atypical TMA presentations.