What are the key clinical features to consider when diagnosing Haemolytic Uraemic Syndrome (HUS) in children?

Key clinical features to consider when diagnosing haemolytic uraemic syndrome (HUS) in children include:

• Microangiopathic hemolytic anemia evidenced by pallor, fatigue, and laboratory findings of anemia with schistocytes on blood film.
• Thrombocytopenia presenting as bruising, petechiae, or bleeding tendencies due to low platelet counts.
• Acute kidney injury manifesting as reduced urine output, oedema, hypertension, and elevated serum creatinine.
• Prodromal diarrhoeal illness, often bloody, typically caused by Shiga toxin-producing Escherichia coli (STEC), preceding the onset of HUS symptoms.
• Other systemic features such as hypertension, neurological symptoms (e.g., irritability, seizures), and gastrointestinal symptoms may also be present.

These features reflect the triad of HUS: hemolytic anemia, thrombocytopenia, and acute kidney injury, which is critical for diagnosis in children ¹ (Donadelli et al., 2023). Atypical HUS, which may be associated with genetic variants such as DGKE mutations, can present similarly but often lacks the diarrhoeal prodrome and may have a more insidious onset (Dai et al., 2023). Therefore, clinical suspicion should be high in children presenting with this triad, especially following a diarrhoeal illness, but also in those with unexplained hemolysis and renal impairment without diarrhoea ¹ (Dai et al., 2023; Donadelli et al., 2023).