Hemolytic-uremic syndrome (HUS) Support Group

The classic childhood 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 disseminated 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.

Adult HUS has similar symptoms and pathology but is an uncommon outcome of the following: HIV; antiphospholipid syndrome (associated with Lupus erythematosus and generalized hypercoagulability); post partum renal failure; malignant hypertension; scleroderma; and cancer chemotherapy (mitomycin, cyclosporine, cisplatin and bleomycin).

A third category is referred to as Familial HUS. It represents 5-10% of HUS cases and is due to an inheritied deficiency leading to uncontrolled complement system activation. Recurrent thromboses result in a high mortality rate.

Treatment is generally supportive with dialysis as needed. Platelet transfusion may actually worsen outcome.