Hemolytic-uremic syndrome

In medicine, Hemolytic-uremic syndrome (or haemolytic-uraemic syndrome, abbreviated HUS) is a disease characterised by microangiopathic hemolytic anemia, acute renal failure and a low platelet count (thrombopenia).

Signs and symptoms

The classic case of HUS occurs after bloody diarrhea caused by E. coli O157:H7, a strain of E. coli that expresses verotoxin (also called Shiga toxin). The toxin enters the bloodstream, attaches to renal endothelium and initiates an inflammatory reaction leading to acute renal failure (ARF) and diffuse intravascular coagulation (DIC). The fibrin mesh destroys red blood cells and captures thrombocytes, leading to a decrease of both on full blood count.
HUS occurs after 2-7% of all E. coli O157:H7 infections.

Diagnosis

Clinically, HUS can be very hard to distinguish from Thrombotic Thrombocytopenic Purpura (TTP). The laboratory features are almost identical, and not every case of HUS is preceded by diarrhea. The only distinguishing feature is that in TTP, neurological symptoms occur more often, but this is not always the case.

Treatment

Treatment is with dialysis and blood and platelet transfusion. Mortality of HUS is 3-5%.
Often, plasmapheresis is also initiated, when there is diagnostic uncertainty between HUS and TTP.

Prognosis

About one-third of persons with hemolytic-uremic syndrome have abnormal kidney function many years later, and a few require long-term dialysis. Another 8% of persons with hemolytic uremic syndrome have other lifelong complications, such as high blood pressure, seizures, blindness, paralysis, and the effects of having part of their bowel removed.

previous.gif (72x17 -- 347 bytes) next.gif (72x17 -- 277 bytes)

Are you a Doctor, Pharmacist, PA or a Nurse?

Join the Doctors Lounge online medical community

  • Editorial activities: Publish, peer review, edit online articles.

  • Ask a Doctor Teams: Respond to patient questions and discuss challenging presentations with other members.

Doctors Lounge Membership Application

Tools & Services: Follow DoctorsLounge on Twitter Follow us on Twitter | RSS News | Newsletter | Contact us