Identifying early clinical and biological factors associated with severe forms of postdiarrheal hemolytic uremic syndrome (D+HUS) that may help practitioners determine appropriate treatment.

This retrospective study was conducted in 49 children with D+HUS between 2001 and 2011. Severe forms were defined as occurrence of one of the following conditions: death, major neurological involvement, cardiovascular involvement, and/or the presence of sequelae (neurological, cardiovascular, pancreatic, or renal).

During the acute phase, 35 children exhibited at least one type of extrarenal involvement including 13 severe forms with a median delayed occurrence after admission of 4.5 days (range: 1–8) for comatose children and 5 days (range: 2–6) for cardiovascular involvement; 32 children required dialysis and three died. In multivariate analysis, (i) major neurological involvement (n=13), (ii) dialysis (n=32), and (iii) sequelae (n=12) were associated with (i) fever during the prodromal phase requiring dialysis at admission, (ii) C-reactive protein level (CRP) >22mg/L at admission, and (iii) major neurological involvement and a white blood cell count (WBC)>20×10³/mm³ during the acute stage, respectively.

D+HUS is a multiorgan disease with a delayed occurrence of life-threatening extrarenal organ involvement. Severe forms appear to be associated with early biological and clinical inflammatory parameters.