Hemolytic Uremic Syndrome
What is hemolytic uremic syndrome?
Hemolytic uremic syndrome (HUS) refers to a spectrum of conditions characterized by hemolysis (the destruction of red blood cells) and uremia (high levels of urea in the blood) and a decrease in blood platelet counts. These conditions occur because the inside lining of the blood vessels becomes inflamed, causing platelets to stick to the inflamed lining. This makes it much more difficult for red blood cells to pass through the blood vessels. Instead, the red blood cells get stuck and become damaged, and they fail to deliver oxygen to the organs, especially the kidneys — sometimes causing kidney injury or kidney failure.
What causes HUS?
HUS can have many causes. “Typical” HUS happens in some individuals who have an intestinal infection (usually caused by a bacterium called E. coli) or a lung infection (usually caused by a bacterium called Streptococcus pneumoniae).
Occasionally, HUS can be caused by things other than infections, such as exposure to certain medications, pregnancy and high blood pressure. HUS in these contexts can be associated with abnormalities in a part of the immune system called the complement system. The types of HUS that are not caused by an intestinal or lung infection are called atypical hemolytic uremic syndrome or aHUS. This type of HUS is often caused by changes in genes that help code for parts of the body’s immune system.
Who gets HUS?
HUS can affect individuals of all ages, ethnicities and genders, but it is more common in children.
What are the signs and symptoms of HUS?
Initial signs and symptoms can include:
Because all forms of HUS damage the blood vessels, children can also experience the following symptoms:
- Pallor (a pale appearance, especially showing loss of color in the face)
- Fatigue or weakness
- Unusual or unexplained bruising
- Body swelling, especially in the legs, ankles or feet
- Decreased urination, sometimes with blood in the urine
- High blood pressure
- Changes in mental status or seizures
- Kidney injury or failure
What tests are used to diagnose HUS?
Blood tests that show blood cell counts and kidney function usually support the diagnosis of HUS. We may also test your child’s stool for E. coli and other organisms that may be associated with HUS. To develop a comprehensive treatment plan, we may also need to perform additional testing to assess the involvement of other organs and, in aHUS, to try and pinpoint a specific cause. Your child’s treatment team may recommend genetic testing to help diagnose the cause of HUS.
Why choose us to diagnose HUS?
The Pediatric Kidney Center at Children’s Colorado has vast experience in diagnosing and treating all forms of HUS. Moreover, we are one of a few centers in the nation with quick access to the diagnostic tests needed to evaluate children suspected to have some form of aHUS.
How is HUS treated?
HUS associated with an intestinal infection (typical HUS) is treated supportively, meaning we use treatments to address or combat the symptoms of the condition. These treatments include blood transfusions for severe anemia (low red blood cells) and kidney support as indicated. In children with kidney injury, diuretic or blood pressure medications might be needed. If HUS causes severe kidney failure, your child may need kidney dialysis treatment.
If there is evidence of a possible genetic cause of HUS, a drug that targets a part of the immune system (called the complement system) may also be needed as part of the treatment of aHUS.
Why choose us for treat HUS?
Our Kidney Care Center team treats all forms of HUS and has extensive experience treating the condition and its underlying causes. In contrast to many other pediatric centers in the country, we also offer enrollment into clinical trials aiming to advance cutting-edge treatment options for aHUS. Backed by our HUS research and experience in treating this syndrome, we can offer optimal treatment. Because our hospital has such a wide range of specialty departments, we can also treat underlying causes all in one location.
- The National Kidney Foundation (NKF) supports people affected by kidney disease, including HUS, by funding scientific research and innovation, and enhancing the lives of those affected by HUS through action, education and accelerating change.
- The aHUS Foundation is made up of advocates from medical and pharmaceutical circles that help doctors and patients understand and respond to aHUS. They champion continued investment in research and therapies that improve the quality of life for aHUS patients.
Contact the Pediatric Nephrology department
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