Hemolytic uremic syndrome (HUS) is a condition that affects blood vessels in your kidneys. It damages your kidneys and may cause blood clots. E.coli is the most common cause of HUS. In most cases, symptoms include diarrhea, abdominal pain, high blood pressure and low urine output. Treatment includes IV fluids, IV blood plasma and medications.
Hemolytic uremic syndrome (hee-mah-lit-ick yer-ee-mik sin-drohm) is a medical condition that blocks the small blood vessels in your kidneys. The blockage destroys your red blood cells (hemolytic anemia) and reduces the number of platelets (thrombocytopenia), which are clotting cells. Hemolytic uremic syndrome (HUS) most commonly affects your kidneys.
Atypical hemolytic uremic syndrome is typically a genetic condition, which means birth parents pass it down to their children. Mutations in some of your genes that encode proteins cause aHUS. Another illness, an infection or an environmental factor triggers the mutation to activate.
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Anyone can develop HUS. However, you’re more likely to develop it if you:
Hemolytic uremic syndrome has a prevalence of between 5% and 15% in people who have E. coli.
Hemolytic uremic syndrome symptoms include:
In severe cases of HUS, damaged red blood cells can clog the tissue in your kidneys. As a result, your kidneys can’t filter and eliminate waste from your body. If your kidneys can’t filter and eliminate waste, it can lead to acute kidney injury.
Symptoms of acute kidney injury include:
If you have diarrhea, it doesn’t mean you have HUS. However, you should seek medical attention if you have bloody diarrhea or severe diarrhea (when you can’t stay hydrated, or it lasts longer than three days).
A medical triad is a group of three signs that indicate a medical condition.
The classic triad associated with HUS includes damage to your red blood cells (microangiopathic hemolytic anemia), a steady decrease in the number of platelets in your blood (thrombocytopenia) and acute kidney injury.
Certain strains of the bacteria E. coli cause most cases of hemolytic uremic syndrome. These strains of E. coli make you sick by producing a toxin called Shiga. Shiga damages the lining of your small intestines and causes diarrhea. It can also enter your bloodstream, destroy red blood cells and damage your kidneys.
Another name for these strains is Shiga toxin-producing E. coli (STEC). The most common STEC in North America is E. coli O157:H7, or E. coli O157.
Rarely, certain medications may cause HUS.
E. coli usually enters your body when you eat spoiled, undercooked or poorly processed foods or drinks. These may include:
E. coli can also spread from person to person through an oral-fecal route. “Oral-fecal” means that harmful strains of E. coli spread when people don’t wash their hands thoroughly with soap and water after they use the bathroom or touch feces (poop). You may touch poop after changing diapers or incontinence garments. You may also touch poop after petting zoo or farm animals that have soiled fur. If you have harmful E. coli bacteria on your hands, it can enter your system when it transfers to the food you eat, or you put your fingers in your mouth.
HUS isn’t contagious. You can’t get HUS from person-to-person contact.
However, you can get E. coli after consuming contaminated food or drinks or contact with a contaminated person’s or animal’s poop.
Your healthcare provider will diagnose hemolytic uremic syndrome. They’ll ask you about your medical history and family medical history. They’ll also conduct a physical exam and order tests.
Your healthcare provider may order the following tests:
Tests look for the presence of different things that indicate hemolytic uremic syndrome.
Urine tests look for blood or protein in your pee. Blood tests detail your red blood cell levels and platelet levels. They can also tell your healthcare provider how well your kidneys and liver are functioning. Stool tests check for the presence of E. coli O157. A kidney biopsy shows damage to your kidney.
Hemolytic uremic syndrome treatment may include blood transfusions, especially red blood cells and platelets. Red blood cells help with signs and symptoms of anemia, including chills, fatigue, shortness of breath and rapid heart rate. Platelets help your blood clot, especially if you’re bleeding or bruising easily.
You may have a greater chance of getting an infection during treatment, so it’s a good idea to wash your hands often and distance yourself from people with infections, including a common cold or the flu.
Your healthcare provider may also give you intravenous (IV) fluids to keep you hydrated.
If you have severe kidney failure, you may need dialysis to keep your blood clean while your kidneys heal. Dialysis is usually temporary.
If you have high blood pressure due to kidney failure, you may have to take medications to bring it down.
Eculizumab and ravulizumab increase your chances of developing meningococcal disease and pneumococcal disease. Your provider will prescribe meningococcal and pneumococcal vaccinations before starting the medications. They may also prescribe antibiotics for at least two weeks.
Talk to your provider if you’re pregnant, planning on getting pregnant or breastfeeding before taking eculizumab or ravulizumab. You must be aware of the benefits and risks to you and your baby.
Yes, you can recover from hemolytic uremic syndrome. If you have HUS, you can recover without permanent damage to your health.
Children have an easier time recovering from HUS than adults. More than 85% of people with HUS recover complete kidney function.
However, even with full recovery, you may have high blood pressure or other kidney problems in the future.
The following tips can help you prevent HUS due to E. coli O157:
With proper diagnosis and care, most people with HUS recover without permanent damage to their health. If you don’t treat HUS, it can be fatal.
Contact your healthcare provider if you have:
Previously, healthcare providers grouped HUS and thrombocytopenic thrombotic purpura (TTP) together. HUS and TTP are similar disorders. TTP causes blood clots to form in your small blood vessels.
Healthcare providers once referred to them as HUS/TTP because they had similar symptoms. Now, healthcare providers recognize them as separate conditions.
A note from Cleveland Clinic
Hemolytic uremic syndrome is a serious condition that affects the blood vessels in your kidneys. Most people get HUS from E. coli. The best and easiest way to avoid an E. coli infection is to regularly wash your hands with soap and water, especially after handling raw foods, before eating, after using the bathroom and after changing diapers.
If you have diarrhea for more than three days or bloody diarrhea, feel tired, look pale and don’t pee a lot when you use the bathroom, see your healthcare provider right away. The sooner you treat HUS, the less risk you have of developing lasting harm to your kidneys.
Last reviewed by a Cleveland Clinic medical professional on 09/06/2022.
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