What is the most common preceding infection associated with Hemolytic Uremic Syndrome?

Hemolytic Uremic Syndrome (HUS) is most commonly associated with infections caused by specific strains of Escherichia coli, particularly Enterohemorrhagic E. coli (EHEC), commonly referred to as Shiga toxin-producing E. coli (STEC). This bacterial infection often precedes HUS, especially in children. The mechanism involves the toxins produced by the bacteria that can damage endothelial cells in the kidneys, leading to the clinical manifestations of hemolytic anemia, acute renal failure, and thrombocytopenia that characterize HUS.

Previous infections, such as those caused by influenza or respiratory syncytial virus, do not usually lead to HUS, nor do infections with streptococcal bacteria. While infections can trigger various complications and syndromes, the strong association of STEC with HUS is well-documented in clinical studies, confirming that E. coli infection is the most common preceding condition linked to this serious syndrome. Understanding this connection is vital for clinicians in pediatrics, as early identification of the infection can lead to more timely and appropriate management of afflicted children.