Hemolytic Uremic Syndrome: Causes, Symptoms, Diagnosis, Treatment, and Prevention
Hemolytic uremic syndrome (HUS) is a rare but serious condition that affects the blood and kidneys. Red blood cells destroy tiny blood vessels in the kidneys, causing kidney failure and other complications.
Causes
A bacteria strain called Escherichia coli (E. coli) O157:H7 is the most common cause of HUS. Infections can occur in food or water contaminated with this strain, including raw fruits and vegetables, raw milk, and undercooked meat. As a result of the bacteria's toxin, the blood vessels are damaged and red blood cells are destroyed.
Other causes of HUS include:
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Genetic mutations that affect the proteins that regulate blood clotting
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Certain medications, such as chemotherapy, immunosuppressants, or antiplatelet drugs
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Other infections, such as pneumonia, HIV, or influenza
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Pregnancy complications, such as preeclampsia or eclampsia
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Autoimmune diseases, such as lupus or scleroderma
Symptoms
The symptoms of HUS usually develop within a week after the onset of diarrhea caused by E. coli infection. However, some people may not have diarrhea or may have mild symptoms. The symptoms of HUS may include:
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Bloody or decreased urine output
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Swelling of the face, hands, feet, or body
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Fatigue, weakness, or lethargy
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Pale skin, bruising, or bleeding
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Fever, headache, or abdominal pain
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Nausea, vomiting, or diarrhea
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Confusion, seizures, or coma
Diagnosis
HUS is diagnosed based on the medical history, physical examination, and laboratory tests. The laboratory tests may include:
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Blood tests to check the levels of red blood cells, platelets, hemoglobin, creatinine, and urea
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Urine tests to check for blood, protein, and bacteria
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Stool tests to check for E. coli or other pathogens
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Kidney biopsy to examine the tissue under a microscope
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Genetic tests to identify any mutations that may cause HUS
Treatment
The treatment of HUS depends on the severity of the condition and the underlying cause. The main goals of treatment are to:
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Support the kidney function and prevent further damage
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Replace the lost blood cells and platelets
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Treat the infection and remove the toxin
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Manage the symptoms and complications
The treatment options may include:
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Fluids and electrolytes to prevent dehydration and maintain the blood pressure
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Blood transfusions to replenish the red blood cells and platelets
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Dialysis to filter the waste and excess fluid from the blood
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Plasma exchange to remove the antibodies and toxins from the blood
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Antibiotics to treat the bacterial infection
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Antihypertensive drugs to lower the blood pressure
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Pain relievers to ease the discomfort
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Surgery to remove the damaged kidney or part of the intestine
Prevention
HUS can be prevented by avoiding or reducing the exposure to the E. coli bacteria and other risk factors. Some of the preventive measures are:
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Washing the hands thoroughly with soap and water before and after handling food, using the bathroom, changing diapers, or touching animals
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Cooking the meat well and avoiding cross-contamination with raw meat or juices
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Drinking only pasteurized milk and juice and avoiding unpasteurized dairy products
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Washing the fruits and vegetables thoroughly before eating or peeling them
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Storing the food properly and refrigerating the leftovers promptly
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Drinking only clean and safe water and avoiding untreated water sources
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Following the doctor’s advice on the use of medications and supplements
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Seeking medical attention promptly if diarrhea, fever, or other symptoms occur
