Hemolytic-uremic syndrome
HUS; STEC-HUS
Shiga-like toxin producing E coli hemolytic-uremic syndrome (STEC-HUS) is a disorder that most often occurs when an infection in the digestive system produces toxic substances. These substances destroy red blood cells and cause kidney injury.
Causes
Hemolytic-uremic syndrome (HUS) often occurs after a gastrointestinal infection with E coli bacteria ( Escherichia coli O157:H7). However, the condition has also been linked to other gastrointestinal infections, including shigella and salmonella . It has also been linked to nongastrointestinal infections.
Shigella
Shigellosis is an infection of the lining of the intestines. It is caused by a group of bacteria called shigella.
Salmonella
Salmonella enterocolitis is an infection in the lining of the small intestine that is caused by salmonella bacteria. It is a type of food poisoning....
HUS is most common in children. It is the most common cause of acute kidney failure in children. Several large outbreaks have been linked to undercooked hamburger meat contaminated with E coli .
STEC-HUS is not to be confused with atypical HUS (aHUS) which is not infection-related. It is similar to another disease called thrombotic thrombocytopenic purpura (TTP).
Thrombotic thrombocytopenic purpura
Thrombotic thrombocytopenic purpura (TTP) is a blood disorder that causes blood clots to form in small blood vessels. This leads to a low platelet c...
Symptoms
STEC-HUS often begins with vomiting and diarrhea, which may be bloody. Within a week, the person may become weak and irritable. People with this condition may urinate less than normal. Urine output may almost stop.
Red blood cell destruction leads to symptoms of anemia .
Anemia
Anemia is a condition in which the body does not have enough healthy red blood cells. Red blood cells provide oxygen to body tissues. Different type...
Early symptoms:
-
Blood in the stools
Blood in the stools
Bloody stools often are a sign of a problem in the digestive tract. Blood in the stool may come from anywhere along your digestive tract from your m...
- Irritability
-
Fever
Fever
Fever is the temporary increase in the body's temperature in response to a disease or illness. A child has a fever when the temperature is at or abov...
-
Lethargy
Lethargy
Fatigue is a feeling of weariness, tiredness, or lack of energy.
-
Vomiting
and
diarrhea
Vomiting
Nausea is feeling an urge to vomit. It is often called "being sick to your stomach. "Vomiting or throwing-up is forcing the contents of the stomach ...
- Weakness
Later symptoms:
-
Bruising
Bruising
Bleeding into the skin can occur from broken blood vessels that form tiny red dots (called petechiae). Blood also can collect under the tissue in la...
-
Decreased consciousness
Decreased consciousness
Decreased alertness is a state of reduced awareness. A coma is a state of decreased alertness from which a person cannot be awakened. A long-term co...
-
Low urine output
Low urine output
Decreased urine output means that you produce less urine than normal. Most adults make at least 500 ml of urine in 24 hours (a little over 2 cups)....
-
No urine output
No urine output
Decreased urine output means that you produce less urine than normal. Most adults make at least 500 ml of urine in 24 hours (a little over 2 cups)....
-
Pallor
Pallor
Paleness is an abnormal loss of color from normal skin or mucous membranes.
-
Seizures
-- rare
Seizures
A seizure is the physical findings or changes in behavior that occur after an episode of abnormal electrical activity in the brain. The term "seizure...
-
Skin rash that looks like fine red spots (
petechiae
)
Petechiae
Bleeding into the skin can occur from broken blood vessels that form tiny red dots (called petechiae). Blood also can collect under the tissue in la...
- Yellow skin (jaundice)
Exams and Tests
The health care provider will perform a physical exam. This may show:
- Liver or spleen swelling
- Nervous system changes
Laboratory tests will show signs of hemolytic anemia and acute renal failure . Tests may include:
Hemolytic anemia
Anemia is a condition in which the body does not have enough healthy red blood cells. Red blood cells provide oxygen to body tissues. Normally, red ...
Acute renal failure
Acute kidney failure is the rapid (less than 2 days) loss of your kidneys' ability to remove waste and help balance fluids and electrolytes in your b...
-
Blood clotting tests (
PT
and
PTT
)
PT
Prothrombin time (PT) is a blood test that measures the time it takes for the liquid portion (plasma) of your blood to clot. A related blood test is ...
PTT
Partial thromboplastin time (PTT) is a blood test that looks at how long it takes for blood to clot. It can help tell if you have a bleeding problem...
-
Comprehensive metabolic panel
may show increased levels of
BUN
and
creatinine
Comprehensive metabolic panel
A comprehensive metabolic panel is a group of blood tests. They provide an overall picture of your body's chemical balance and metabolism. Metaboli...
BUN
BUN stands for blood urea nitrogen. Urea nitrogen is what forms when protein breaks down. A test can be done to measure the amount of urea nitrogen ...
Creatinine
The creatinine blood test measures the level of creatinine in the blood. This test is done to see how well your kidneys are working. Creatinine can ...
-
Complete blood count
(CBC) may show increased white blood cell count and decreased red blood cell count
Complete blood count
A complete blood count (CBC) test measures the following:The number of red blood cells (RBC count)The number of white blood cells (WBC count)The tota...
-
Platelet
count is usually reduced
Platelet
A platelet count is a lab test to measure how many platelets you have in your blood. Platelets are parts of the blood that help the blood clot. The...
-
Urinalysis
may reveal blood and protein in the urine
Urinalysis
Urinalysis is the physical, chemical, and microscopic examination of urine. It involves a number of tests to detect and measure various compounds th...
-
Urine protein
test can show the amount of protein in the urine
Urine protein
The protein urine dipstick test measures the presence of proteins, such as albumin, in a urine sample. Albumin and protein can also be measured using...
Other tests:
-
Kidney biopsy
Kidney biopsy
A kidney biopsy is the removal of a small piece of kidney tissue for examination.
-
Stool culture
may be positive for a certain type of
E coli
bacteria or other bacteria
Stool culture
A fecal culture is a lab test to find organisms in the stool (feces) that can cause gastrointestinal symptoms and disease.
Treatment
Treatment may involve:
- Dialysis
- Medicines such as corticosteroids
- Transfusions of packed red blood cells and platelets
Outlook (Prognosis)
This is a serious illness in both children and adults, and it can cause death. With proper treatment, more than half of people will recover. The outcome is better in children than adults.
Possible Complications
Complications may include:
- Blood clotting problems
-
Hemolytic anemia
Hemolytic anemia
Anemia is a condition in which the body does not have enough healthy red blood cells. Red blood cells provide oxygen to body tissues. Normally, red ...
- Kidney failure
- Nervous system problems
-
Too few platelets (
thrombocytopenia
)
Thrombocytopenia
Thrombocytopenia is any disorder in which there is an abnormally low amount of platelets. Platelets are parts of the blood that help blood to clot. ...
-
Uremia
Uremia
Prerenal azotemia is an abnormally high level of nitrogen waste products in the blood.
When to Contact a Medical Professional
Call your provider if you develop symptoms of HUS. Emergency symptoms include:
- Blood in the stool
- No urination
- Reduced alertness (consciousness)
Call your provider if you have had an episode of HUS and your urine output decreases, or you develop other new symptoms.
Prevention
You can prevent the known cause, E coli , by cooking hamburger and other meats well. You should also avoid contact with unclean water.
References
Abrams CS. Thrombocytopenia. In: Goldman L, Schafer AI, eds. Goldman's Cecil Medicine . 25th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 172.
Ruggenenti R, Cravedi P, Remuzzi G. Microvascular and macrovascular diseases of the kidney. In: Skorecki K, Chertow GM, Marsden PA, Taal MW, eds. Brenner and Rector's The Kidney . 10th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 35.
Van Why SK, Avner ED. Hemolytic-uremic syndrome. In: Kliegman RM, Stanton BF, St Geme JW, Schor NF, eds. Nelson Textbook of Pediatrics . 20th ed. Philadelphia, PA: Elsevier; 2016:chap 518.
Review Date: 2/1/2016
Reviewed By: Todd Gersten, MD, Hematology/Oncology, Florida Cancer Specialists & Research Institute, Wellington, FL. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.