Vol. 7, Issue 4, Part A (2025)

While most Escherichia coli (E. coli) strains are benign, some might generate toxins capable of causing severe disease. Heat-stable enterotoxins as well as Shiga toxins are the two most significant toxins linked to pathogenic E. coli. Here are a few details regarding such toxins: Shiga toxins: Usually the Enterohemorrhagic Escherichia coli (EHEC) serotype, such toxins—also referred to as verocytotoxins or Shiga-like toxins-are generated by some E. coli strains, most especially E. coli O157:H7. Two primary forms of Shiga toxins are Stx1 and Stx2. Diseases such as hemorrhagic colitis and HUS (hemolytic uremic syndrome) have their origins in them. Infection with STEC (Shiga toxin-producing E. coli) could cause colonic inflammation that results in bloody diarrhea, abdominal pain, and occasionally fever. Particularly in young children, HIS (hemolytic uremic syndrome) is a serious condition which could accompany a STEC infection. Kidney damage, low platelet count, and red blood cell destruction define HUS and might lead to acute renal failure. Diarrhea is caused by heat-stable enterotoxins (STb and STa) produced by enterotoxin Escherichia coli (ETEC) strains. Acting on the small intestine's lining, such toxins disrupt fluid absorption and induce too strong water and electrolyte secretion, which causes watery diarrhea. Apart from Shiga toxins as well as heat-stable enterotoxin, several E. coli strains generate additional toxins that aggravate disease. EPEC, for instance, generates bundle-forming pili (BFP), intimin, and a type III secretion system—all of which are involved in the attachment as well as effacement of intestinal cells, hence causing diarrhea. E. coli infections could range in degree; hence not all strains generate toxins. Sanitation, hygienic practices, and proper food safety precautions help lower E. coli risk. Should you believe you have an E. coli infection, you should see a doctor for a correct treatment and diagnosis recommendation.