Which strain of E. coli is known for causing hemolytic uremic syndrome?

• A. Enterotoxigenic E. coli
• B. Enteropathogenic E. coli
• C. Enterohemorrhagic E. coli
• D. Uropathogenic E. coli

Answer: (C)

The strain of E. coli known for causing hemolytic uremic syndrome (HUS) is enterohemorrhagic E. coli (EHEC). This particular strain produces a potent toxin called Shiga toxin, which can lead to severe gastrointestinal illness characterized by bloody diarrhea. The toxin damages the lining of the intestinal blood vessels, leading to the destruction of red blood cells and subsequently to kidney complications, which can result in HUS. HUS is particularly dangerous and can lead to acute renal failure, making EHEC a significant public health concern.

Understanding EHEC is crucial because it highlights the importance of food safety and the risks associated with undercooked beef and contaminated produce, where this strain is often implicated in outbreaks. The other strains mentioned, while associated with different disease mechanisms and symptoms, do not cause HUS. For instance, enterotoxigenic E. coli is primarily associated with traveler's diarrhea, enteropathogenic E. coli causes diarrhea primarily in infants, and uropathogenic E. coli is linked to urinary tract infections but not to HUS. This distinction emphasizes the unique pathogenic profile of enterohemorrhagic E. coli.