Small bowel (small intestine)
Infectious disorders
Bacterial enterocolitis

Author: Hanni Gulwani, M.D. (see Authors page)

Revised: 14 February 2018, last major update August 2012

Copyright: (c) 2003-2018, PathologyOutlines.com, Inc.

PubMed Search: Bacterial enterocolitis small bowel[TIAB]

Cite this page: Gulwani, H. Bacterial enterocolitis. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/smallbowelbacterialenterocolitis.html. Accessed June 25th, 2018.
Definition / general
  • Bacterial related disease due to either ingestion of preformed toxin (Staphylococcus aureus, Vibrio cholera, Clostridium perfringens), infection by toxigenic organisms or infection by enteroinvasive organisms which invade and destroy mucosal epithelium cells (eMedicine: Bacterial Gastroenteritis [Accessed 14 February 2018])
  • Bacterial adhere to mucosal epithelial cells, elaborate enterotoxins, have capacity to invade
  • Adhere by plasmid mediated adhesins (E. coli, V. cholera), fimbriae or pili
  • Adhesion destroys microvilli brush border
Clinical features
  • Complications due to massive fluid loss and loss of mucosal barrier include dehydration, sepsis, perforation
  • Salmonella: invades via transcytosis with minimal epithelial damage
  • Yersinia enterocolitica: penetrates ileal mucosa, multiplies in Peyer patches and regional lymph nodes
  • Insidious infection: Yersinia and Mycobacterium tuberculosis
  • Cytotoxins: Shiga toxin, enterohemorrhagic E. coli

Enterotoxins:
  • Bind to cell membrane, enter cell, activates massive electrolyte secretion (cholera toxin, E. coli heat labile and heat stable toxins produce traveler's diarrhea)
  • No white blood cells in stool

Bacterial invasion:
  • Enteroinvasive E. coli and Shigella have plasmid that mediates epithelial cell invasion via microbe simulated endocytosis; then intracellular proliferation, cell lysis, cell to cell spread

Patients ingest preformed toxins:
  • Symptoms within hours
  • Explosive diarrhea and acute abdominal distress
  • 1 - 2 days
  • C. botulinum may produce rapid, fatal respiratory failure

Infection with enteric pathogens:
  • Incubation of hours - days
  • Diarrhea and dehydration (secretory enterotoxin) or dysentery (cytotoxin or enteroinvasive)

Traveler's diarrhea:
  • Fecally contaminated water / food
  • Begins abruptly, subsides in 2 - 3 days
Microscopic (histologic) description
  • Decreased epithelial cell maturation, increased mitotic figures, hyperemia and edema of lamina propria, variable neutrophils, modest villus blunting of small bowel
  • Late: lymphocytes, plasma cells, regenerative change
Differential diagnosis