Hemolytic uremic syndrome by Streptococcus pneumoniae

Hemolytic uremic sindrome (HUS) is an acute disease characterized by microangiopathic hemolytic anemia, thrombocytopenia, and acute renal failure, usually, but not always, associated with the prodrome of diarrhea. A 2-year-6-month old boy with pneumonia caused by Streptococcus pneumoniae developed the third day after admission oliguric acute renal failure, anemia, and thrombocytopenia. The patient needed veno-venous hemodiafiltration/ hemofiltration during ten days. He received five packed red blood cell, and one platelet transfusions, and was treated with plasma infusions during six days. Renal function was normal at discharge. HUS caused by Streptococcus pneumoniae has more morbility and mortality that classic HUS, although they usually recovery renal function. In those cases of atypical HUS, different from others, blood transfusions that contains IgM should be avoided, because they can increase antigen-antibody reaction and cellular damage. The low incidence of HUS by Streptococcus pneumoniae and the systemic infectious component difficult the early diagnosis. Taking into account the different transfusion approach in these cases, it is necessary to be aware for diagnosing HUS by Streptococcus pneumoniae in all patients with systemic infection and sudden renal function deterioration.