Bacterium
Enterotoxigenic E. coli (ETEC)
Toxin-driven watery traveler's diarrhea pathotype
en-ter-oh-tok-sih-JEN-ik
High-yield clue
Non-invasive watery (secretory) diarrhea from heat-labile (LT) and heat-stable (ST) enterotoxins is the defining pathotype clue.
Overview
A diarrheagenic pathotype of Escherichia coli defined by its production of secretory enterotoxins rather than by invasion. It is the leading cause of travelers' diarrhea and a major cause of childhood watery diarrhea in low-resource settings.
Classification
- Gram-negative
- Diarrheagenic E. coli pathotype
- Toxin-mediated (non-invasive)
- Enterobacterales
Lab & identification clues
- LT and ST enterotoxin gene detection (PCR) vocabulary
- Colonization-factor fimbriae adhesion concept
- No mucosal invasion (non-inflammatory stool) framing
- Not distinguished from flora by routine stool culture
Associations
- Travelers' diarrhea study association
- Fecal-oral, contaminated food and water transmission
- LT raises cAMP (cholera-toxin-like mechanism)
- ST raises cGMP driving fluid secretion
Commonly confused with
- Vibrio cholerae (LT resembles cholera toxin)
- Shiga toxin-producing E. coli (STEC)
Frequently asked questions
What is Enterotoxigenic E. coli (ETEC)?
A diarrheagenic pathotype of Escherichia coli defined by its production of secretory enterotoxins rather than by invasion. It is the leading cause of travelers' diarrhea and a major cause of childhood watery diarrhea in low-resource settings.
What is the Gram stain of Enterotoxigenic E. coli (ETEC)?
Enterotoxigenic E. coli (ETEC) is Gram negative.
What are the lab clues for Enterotoxigenic E. coli (ETEC)?
Lab clues for Enterotoxigenic E. coli (ETEC) include LT and ST enterotoxin gene detection (PCR) vocabulary, Colonization-factor fimbriae adhesion concept, No mucosal invasion (non-inflammatory stool) framing, and Not distinguished from flora by routine stool culture.
What is Enterotoxigenic E. coli (ETEC) commonly confused with?
Enterotoxigenic E. coli (ETEC) is commonly confused with Vibrio cholerae (LT resembles cholera toxin) and Shiga toxin-producing E. coli (STEC).
Original student-study summary. Sources checked: OpenStax Microbiology 2e, NCBI Bookshelf Medical Microbiology, and CDC topic pages where applicable; reviewed 2026-06. Educational only; no diagnosis, treatment, dosing, or specimen-handling guidance.