Hemolytic Uremic Syndrome: Causes, Symptoms, and Treatment
Medically reviewed by Harsha Moole, MD, Internal Medicine. Last reviewed: October 23, 2026.
What kind of doctor treats Hemolytic Uremic Syndrome?
A nephrologist, a kidney doctor, usually leads care for hemolytic uremic syndrome. A pediatric nephrologist treats children, and a hematologist, a blood doctor, may also help. Children are often watched closely in the hospital. A direct primary care or concierge doctor can be a first stop for an evaluation and can refer you to a specialist when needed.
What is hemolytic uremic syndrome?
Hemolytic uremic syndrome, or HUS, is a kidney condition. It happens when red blood cells are destroyed and block the kidneys' filtering system. It is the most common cause of acute kidney failure in children.
The most common form is called STEC-HUS. It usually starts when an infection in the digestive system makes toxic substances. These substances destroy red blood cells and injure the kidneys.
A rarer form is atypical HUS. It is not caused by the usual E. coli infection. It has three main features: hemolytic anemia, a low platelet count, and kidney failure.
Symptoms
STEC-HUS often begins with vomiting and diarrhea, which may be bloody. Within a week, the person may become weak and irritable. Other early signs include:
- Fever.
- Lethargy, which means being very sleepy and low on energy.
- Weakness.
Destroyed red blood cells lead to anemia, which means too few red blood cells. Signs of anemia include tiredness, weakness, and paleness.
The kidneys may make less urine. Urine output may almost stop. Later signs can include:
- Bruising.
- Swelling, most often in the legs, feet, or ankles.
- Blood in the urine.
- A skin rash that looks like fine red spots.
- Seizures, which are rare.
Causes and who gets it
The most common cause in children is an infection of the digestive system with the O157:H7 type of E. coli bacteria. The bacteria make toxins that can enter the blood and destroy red blood cells. This E. coli can be found in undercooked meat, most often ground beef, raw milk, unwashed raw fruits and vegetables, contaminated juice, and contaminated pools or lakes. It can also spread from one person to another.
HUS has also been linked to other digestive infections, including shigella and salmonella.
Less common causes include certain medicines, such as chemotherapy, other viral or bacterial infections, and an inherited form that runs in families.
Atypical HUS often comes from a mix of genes and outside triggers. Triggers can include infections and pregnancy.
Children are more likely to get HUS if they are younger than 5 and have an E. coli O157:H7 infection, have a weak immune system, or have a family history of inherited HUS.
How doctors diagnose it
A doctor uses a medical and family history, a physical exam, urine tests, blood tests, a stool test, and sometimes a kidney biopsy. A kidney biopsy takes a small piece of kidney tissue to study under a microscope.
Blood tests check red blood cell and platelet levels and kidney function. A blood smear can show broken red blood cells. A stool test can show E. coli O157:H7.
Treatment
Care focuses on urgent symptoms and on protecting the kidneys. Doctors may:
- Watch the child closely in the hospital.
- Replace fluids and minerals through an IV tube.
- Give red blood cells and platelets through an IV.
- Treat high blood pressure with medicines.
If the kidneys fail, dialysis may be needed. Dialysis filters wastes and extra fluid from the body with an artificial kidney. Most children need it for a short time only.
Atypical HUS is treated differently. Doctors now use medicines that block an overactive part of the immune system, such as eculizumab and ravulizumab. Before starting them, people need a meningococcal vaccine, because these medicines raise the risk of that infection.
In most cases, children with HUS are not treated with antibiotics unless they have an infection in another part of the body. Some children have lasting kidney damage. They may need dialysis or a kidney transplant.
When to see a doctor
Contact your provider if you develop symptoms of HUS. Emergency symptoms include blood in the stool, no urination, and reduced alertness.
Call 911 or go to the emergency room for those emergency symptoms or if you have a seizure, bleeding that will not stop, or severe belly pain.
How a direct primary care or concierge doctor fits in
A direct primary care doctor charges a flat monthly fee instead of billing insurance, while a concierge doctor usually charges more and often works alongside insurance. A direct primary care doctor can check early symptoms and order basic tests. They can also coordinate follow-up with kidney and blood specialists after a hospital stay.
Common questions
Is hemolytic uremic syndrome serious?
Yes, it is a serious illness in both children and adults, and it can cause death. Many children recover well.
Is atypical HUS the same as the usual form?
No, they are different conditions. The usual form is caused by certain E. coli bacteria. The atypical form is not caused by those bacteria and is more often genetic.
Can antibiotics treat hemolytic uremic syndrome?
Usually not. Most children with HUS are not treated with antibiotics unless they have an infection in another area of the body.
Can hemolytic uremic syndrome be prevented?
Hemolytic uremic syndrome from E. coli, the known cause, can be prevented. You can lower the risk by cooking hamburger and other meats well, avoiding unclean water, and washing hands well. Also avoid unpasteurized milk, juice, and cider.
Sources
- MedlinePlus - Hemolytic-uremic syndrome
- NORD - Atypical Hemolytic Uremic Syndrome
- NIDDK - Hemolytic Uremic Syndrome in Children
Medical Disclaimer
This content is for general educational and informational purposes only and is not medical advice. It is not a substitute for professional medical advice, diagnosis, or treatment, and reading it does not create a doctor-patient relationship. Always seek the advice of your physician or another qualified health provider with any questions about a medical condition, and never disregard or delay seeking professional advice because of something you read here. If you think you may have a medical emergency, call 911 (or your local emergency number) immediately.
