Decreased severity of Shiga toxin-producingEscherichia colihaemolytic uraemic syndrome (STEC-HUS) in a child with type 1 von Willebrand disease

Shiga toxin-producing Escherichia coli-associated haemolytic uraemic syndrome (STEC-HUS) is characterised by haemolytic anaemia, thrombocytopenia and acute kidney injury. Von Willebrand Factor (vWF) is an important mediator of normal thrombi formation and indirect evidence suggests that vWF may play an important role in Shiga toxin-induced thrombi formation. Clinical evidence supporting the role of vWF in STEC-HUS is lacking. A 10-year-old girl with type 1 von Willebrand Disease (vWD) had a mild case of STEC-HUS, with nadir haemoglobin 7.3 g/dL and platelet count 105×10(9) cells/L and peak serum creatinine 0.56 mg/L and lactate dehydrogenase 741 U/L. This is the first report of STEC-HUS in a patient with vWD. We speculate that the quantitative deficiency of vWF associated with type 1 vWD may have attenuated the course of disease by reducing platelet aggregation, complement activation and thrombi formation. This case adds to a growing literature supporting a link between vWF and STEC-HUS.