[Streptococcus pneumoniae-induced hemolytic uremic syndrome: a serotype-3-associated case]

Hemolytic uremic syndrome (HUS) is the primary cause of acute renal failure in children younger than 3 years of age. It usually occurs after a diarrheal illness due to Shiga-toxin-producing Escherichia coli. Streptococcus pneumoniae (SP)-induced HUS remains rare, involving 5% of all cases of HUS in children, but its frequency has increased over the last decade. The incidence of HUS following invasive pneumococcal infections is estimated at 0.4 to 0.6%. We report here the case of a 3.5-year-old child who presented SP serotype-3-associated HUS. The diagnosis was suspected by the patient's multiple organ failure. The pathogenesis involves the activation of the Thomsen-Friedenreich antigen. To prevent transfusion-associated hemolysis, it is recommended that fresh-frozen plasma or unwashed blood products should be avoided when possible. Our patient was transfused with 4 units of unwashed red blood cell and 2 units of fresh-frozen plasma. No special complication was noted. The risk of immediate complications requires close clinical and biological monitoring, and the possibility of starting dialysis immediately. Twenty-five to 35% of SP-HUS patients exhibit long-term renal aftereffects. The acute mortality rate depends on the site of infection. The increased frequency of SP-HUS may be related to the new ecology of serotypes created by widespread Prevenar7(®) vaccination.