title: Update on Streptococcus pneumoniae associated hemolytic uremic syndrome.
abstract: OBJECTIVE
  Streptococcus pneumoniae associated hemolytic uremic syndrome (SpHUS) is defined by the occurrence of acute hemolytic anemia, thrombocytopenia and acute kidney injury in a patient with a S. pneumoniae infection. We review the pathophysiology, clinical course, treatment and prognosis for SpHUS. We also describe an expanded classification system that uses additional diagnostic criteria to identify more patients with a high likelihood of having SpHUS.
  
  
  RESULTS
  SpHUS often may be underdiagnosed because of overlapping features with disseminated intravascular coagulation (DIC) and the lack of strict diagnostic criteria. The epidemiology has changed with the emergence of different pneumococcal serotypes as newer pneumococcal vaccines have been introduced.
  
  
  CONCLUSIONS
  SpHUS accounts for 5-15% of all HUS cases. The majority of SpHUS patients have pneumonia and a low mortality rate in contrast to those with meningitis, who have a more severe clinical course. Although the pathogenesis of SpHUS remains unknown, the Thomsen-Friedenreich antigen seems to play a central role. S. pneumoniae produces neuraminidase, thereby exposing the Thomsen-Friedenreich antigen on the surface of cell membranes. Thomsen-Friedenreich antigen exposure can result in hemolysis and direct endothelial injury leading to HUS phenotype. Early identification of these patients is critical so that fresh frozen plasma may be avoided.
authors.affiliation: Division of Pediatric Nephrology, Department of Pediatrics, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania 19104, USA.
authors.forename: Joann M
authors.initials: JM
authors.lastname: Spinale
authors.forename: Rebecca L
authors.initials: RL
authors.lastname: Ruebner
authors.forename: Bernard S
authors.initials: BS
authors.lastname: Kaplan
authors.forename: Lawrence
authors.initials: L
authors.lastname: Copelovitch
mesh_terms: D006463:Hemolytic-Uremic Syndrome / Q000175:diagnosis / Q000453:epidemiology / Q000382:microbiology* / Q000628:therapy; D006801:Humans; D011008:Pneumococcal Infections / Q000150:complications* / Q000453:epidemiology / Q000517:prevention & control; D022242:Pneumococcal Vaccines; D011379:Prognosis
chemical_list: D022242:Pneumococcal Vaccines