Hemolytic Uremic Syndrome (HUS): Causes, Symptoms, Treatment & Prevention

What is Hemolytic Uremic Syndrome (HUS)?

Hemolytic Uremic Syndrome (HUS) is a rare but serious condition that affects the blood and kidneys. It occurs when small blood vessels in the kidneys become damaged and inflamed, leading to hemolytic anemia, thrombocytopenia (low platelet count), and acute kidney injury.

HUS is most commonly triggered by an E. coli infection (Shiga toxin-producing E. coli – STEC), but other infections, medications, and genetic factors can also contribute.

Causes of Hemolytic Uremic Syndrome

HUS can be classified into different types based on its cause:

1. Shiga Toxin-Producing E. coli (STEC-HUS):

   • Caused by contaminated food, water, or contact with infected individuals.

   • Common culprits: undercooked meat, unpasteurized dairy, and contaminated produce.

2. Atypical HUS (aHUS):

   • A genetic form of HUS linked to uncontrolled complement system activity.

   • Can be triggered by infections, pregnancy, or certain medications.

3. Secondary HUS:

   • Develops due to conditions like autoimmune diseases, cancer, or organ transplants.

Symptoms of Hemolytic Uremic Syndrome

HUS symptoms often appear after a gastrointestinal infection (usually E. coli) and include:

✔ Diarrhea (often bloody)
✔ Pale skin, fatigue, and weakness (due to anemia)
✔ Decreased urination (sign of kidney damage)
✔ Swelling in legs, feet, or face
✔ Bruising or unexplained bleeding (due to low platelet count)
✔ High blood pressure

If untreated, severe HUS can lead to kidney failure, neurological complications, and life-threatening conditions.

Diagnosis of HUS

Doctors diagnose HUS based on:

• Blood tests (to check for anemia, platelet count, and kidney function)

• Urine tests (to detect blood and protein levels)

• Stool culture (to identify E. coli infection)

• Kidney function tests (such as creatinine levels and glomerular filtration rate – GFR)

Treatment for Hemolytic Uremic Syndrome

 Supportive Care:

• IV fluids to prevent dehydration and maintain kidney function.

• Blood transfusions for severe anemia.

• Plasma exchange (plasmapheresis) for atypical HUS

If kidneys stop functioning properly, dialysis may be required temporarily.

 Medications:

• Eculizumab (Soliris): Used for atypical HUS to block immune system overactivation.

• Antihypertensive drugs: To manage high blood pressure.

Antibiotics are NOT recommended for STEC-HUS, as they may worsen toxin release.

Prevention of Hemolytic Uremic Syndrome

✅ Safe Food Practices:

• Cook meat thoroughly (avoid undercooked beef).

• Wash fruits and vegetables properly.

• Avoid unpasteurized dairy and juices.

✅ Hand Hygiene:

• Wash hands after using the restroom and before handling food.

• Encourage kids to wash hands regularly.

✅ Avoid Contaminated Water:

• Drink only clean, treated water.

• Be cautious with recreational water sources (pools, lakes, etc.).

Key Takeaways

• HUS is a severe condition that primarily affects the kidneys and blood.

• It is most commonly caused by E. coli infections but can also occur due to genetic or secondary causes.

• Early symptoms include diarrhea, fatigue, and reduced urination.

• Treatment involves supportive care, dialysis (if needed), and in some cases, targeted medications.

• Preventive measures include proper food hygiene, handwashing, and avoiding contaminated water.