Hemolytic uremic syndrome Causes

Hemolytic uremic syndrome has several known causes and some unknown causes. Typically in children, HUS often is caused by an infection with E. coli O157:H7 or other types of bacteria. In adults, HUS is more likely to be caused by an autoimmune disease such AIDS, a blood infection or the use of certain medications.

Causes of hemolytic uremic syndrome include follow:

Escherichia coli O157:H7 infection. In children, HUS often follows a prodromal infectious disease, usually diarrhea (90%) and less often an upper respiratory infection (10%). The most common cause of HUS is a toxin produced by Escherichia coli serotype O157:H7 that a bacteria cause bloody diarrhea in the body. Transmission of E coli O157:H7 appears to be caused by contaminated food, such as ground beef and other cattle products that are undercooked, and unpasteurized dairy products. Food contaminated with E coli does not look, smell, or taste bad. bacterial infection. Additional bacteria infection include Shigella, Salmonella, Yersinia, and Campylobacter species.

Viral infection, including varicella, echovirus, and coxsackie A and B, as well as other infectious agents such as Streptococcus pneumonia and Clostridium difficile. Pneumonia caused by the Streptococcus pneumonia bacteria is another possible precipitating factor. HUS is an unusual complication of this common infection.

HUS has also been associated with AIDS, cancer. Malignancies found in conjunction with HUS include prostatic, gastric, and pancreatic malignancies.

Pregnancy and the early postpartum (after delivery) time period and the use of birth control pills are the more common associations with HUS.

Medications may be also associated with HUS, include oral contraceptives, chemotherapeutic medications (mitomycin C, bleomycin, cisplatinum), immunosuppressive agents used during organ transplantation (cyclosporin, tacrolimus), stroke-preventing drugs (ticlopidine hydrochloride), quinine.

Familial. This cause accounts for 3% of all cases of hemolytic-uremic syndrome (HUS), and both autosomal dominant and autosomal recessive forms of inheritance have been reported. Autosomal recessive HUS occurs in childhood, and patients have a poor prognosis with frequent recurrences and a mortality rate of 60-70%. Autosomal dominant HUS occurs mostly in adults, who have a poor prognosis; the cumulative incidence of death or ESRD is 50-90%.

HUS is more complicated in adults. It is similar to another disease called thrombotic thrombocytopenic purpura (TTP).