Clinical aspects of a nationwide epidemic of severe haemolytic uremic syndrome (HUS) in children

Description of clinical presentation, complications and outcome in a nationwide outbreak.Ten children (median age 4.3 years) developed HUS during the outbreak. One of these was presumed to be a part of the outbreak without microbiological proof. Eight of the patients were oligoanuric and in need of dialysis. Median need for dialysis was 15 days; one girl did not regain renal function and received a kidney transplant. Four patients had seizures and/or reduced consciousness. Cerebral oedema and herniation caused the death of a 4-year-old boy. Two patients developed necrosis of colon with perforation and one of them developed non-autoimmune diabetes.This outbreak of STEC was characterized by a high incidence of HUS among the infected children, and many developed severe renal disease and extrarenal complications. A likely explanation is that the O103:H25 (eae and stx2-positive) strain was highly pathogen, and we suggest that this serotype should be looked for in patients with HUS caused by STEC, especially in severe forms or outbreaks.Haemolytic uremic syndrome (HUS) is a severe, acute and dramatic disease affecting previously healthy children. HUS is defined as a triad of acute kidney injury, microangiopatic haemolytic anaemia and thrombocytopenia in patients with no other explanation for coagulopathy [1] e.g. thrombotic thrombocytopenic purpura. More than 90% of the cases are due to Shiga toxin-producing E. coli (STEC) infections; termed typical HUS or diarrhoea associated HUS (D+HUS). Many different serotypes can cause HUS, the most prevalent in Europe and USA being O157:H7 [2,3]. A broad spectrum of extrarenal complications may occur in HUS, the most common are gastrointestinal and cerebral. Extrarenal involvement at an early stage is associated with increased morbidity and mortality. Although several epidemics, caused by O157 [4] and other serotypes [5] have been reported, the majority of HUS cases appear sporadic or in small clusters [1].In 2006 a nationwide outbr