Hemolytic Uremic Syndrome

Hemolytic uremic syndrome (HUS) is a thrombotic microangiopathy defined by the triad of renal failure, hemolytic anemia, and thrombocytopenia. It is a leading cause of acute kidney injury in young children. HUS is now classified by etiology rather than clinical features, with Shiga toxin-producing Escherichia coli accounting for most pediatric cases. Atypical HUS, most often due to complement dysregulation, is less common and carries a higher risk for chronic renal impairment. Diagnosis is clinical, supported by gastrointestinal symptoms and characteristic laboratory findings. Imaging plays an important role in evaluating complications and guiding treatment. Renal US can help assess disease severity, while neuroimaging is used in patients with suspected central nervous system involvement. Management is primarily supportive, with early hydration and dialysis when indicated. Outcomes depend on the underlying etiology and severity of organ involvement, with neurologic and cardiac complications being the primary drivers of mortality.