Atypical Hemolytic Uremic Syndrome associated with Thrombomodulin genetic variant: a case report

Abstract

Introduction: Atypical Hemolytic Uremic Syndrome (aHUS) is characterized by microangiopathic hemolytic anemia, thrombocytopenia, and acute renal failure, associated with genetic variations in the complement system, such as the THBD gene, responsible for 3-5% of hereditary cases. Case report: A patient with a history of Nephrotic Syndrome developed persistent anemia and thrombocytopenia. Analysis showed ADAMTS 13 activity at 50%. Genetic studies revealed a variant in THBD associated with complement dysfunction. Discussion: The genetic variant in THBD in our patient corresponds to those found in aHUS, which are less common. Complement dysfunction due to the absence of this protein explains the microangiopathy and renal impairment. Eculizumab was initiated early to prevent progression and improve prognosis. Conclusion: aHUS is heterogeneous with multiple genetic causes, including variations in THBD. Identifying these variants is crucial for guiding specific treatments such as Eculizumab, effective in inhibiting the complement pathway. Early genetic diagnosis and individualized management are key in aHUS for better long-term outcomes.