Case Report of Rare Entity for Atypical Hemolytic Uremic Syndrome

Background: Atypical Haemolytic Uremic Syndrome (aHUS) is a genetic or acquired disorder of regulatory component of the complement system. It is associated with mutations in genes coding for complement components. The abnormality in components of complement makes it susceptible and predispose to chronic uncontrolled hyperactivation of the alternative complement pathway, which results in endothelial damage and microvascular thrombosis. This case report describes a patient diagnosed with Thrombotic Microangiopathy (TMA) due to factor H autoantibody having haemolytic anemia, thrombocytopenia and acute kidney injury. Patient’s anemia and renal parameters improved after treatment with plasma exchange therapy. Conclusion: Atypical HUS must be strongly suspected in any patient who presents with nonspecific abdominal or respiratory symptoms along with anemia and thrombocytopenia. As extrarenal involvement is a rare entity of aHUS, the clinician should also keep a high index of suspicion to the possibility of thrombotic microangiopathy manifestation in almost any organ system. In a suspected or diagnosed case of aHUS, the development of new non renal symptoms and signs should prompt clinician for further evaluation to rule out ongoing thrombotic microangiopathy process.