Which statement best differentiates invasive enteric pathogens from enterotoxin-mediated pathogens?

Which statement best differentiates invasive enteric pathogens from enterotoxin-mediated pathogens?

• A. Invasive pathogens invade mucosa causing inflammatory diarrhea (often bloody) via tissue invasion; enterotoxin-mediated pathogens produce toxins that disrupt fluid balance, causing watery diarrhea without invasion.
• B. Invasive pathogens cause watery diarrhea by toxin production; enterotoxin pathogens invade mucosa causing inflammatory diarrhea.
• C. Both categories cause inflammatory diarrhea with blood regardless of mechanism.
• D. Enterotoxin-mediated pathogens invade the mucosa and cause bleeding.

Answer: (A)

Differentiating these two types of enteric pathogens comes down to how they cause diarrhea. Invasive pathogens breach the mucosal surface and trigger an inflammatory response in the gut, damaging the mucosa and often producing fever, abdominal pain, and stools that are inflammatory and sometimes bloody. Enterotoxin-mediated pathogens, on the other hand, do not primarily invade; they release toxins that disrupt ion transport and water absorption in enterocytes, leading to a secretory, watery diarrhea with little or no mucosal inflammation. This distinction is why the statement that invasive pathogens cause inflammatory, often bloody diarrhea via tissue invasion, while enterotoxin producers cause watery diarrhea by toxin effects without invasion, best captures the difference. For context, examples of invasive pathogens include Shigella, Salmonella, Campylobacter, and enteroinvasive E. coli, whereas enterotoxin-mediated examples include Vibrio cholerae and enterotoxigenic E. coli.

Differentiating these two types of enteric pathogens comes down to how they cause diarrhea. Invasive pathogens breach the mucosal surface and trigger an inflammatory response in the gut, damaging the mucosa and often producing fever, abdominal pain, and stools that are inflammatory and sometimes bloody. Enterotoxin-mediated pathogens, on the other hand, do not primarily invade; they release toxins that disrupt ion transport and water absorption in enterocytes, leading to a secretory, watery diarrhea with little or no mucosal inflammation. This distinction is why the statement that invasive pathogens cause inflammatory, often bloody diarrhea via tissue invasion, while enterotoxin producers cause watery diarrhea by toxin effects without invasion, best captures the difference. For context, examples of invasive pathogens include Shigella, Salmonella, Campylobacter, and enteroinvasive E. coli, whereas enterotoxin-mediated examples include Vibrio cholerae and enterotoxigenic E. coli.