Definition
Inflammation of the colon due to E coli O157:H7
Alternate/Historical Names
Verocytotoxin (verotoxin) producing E coli colitis
Diagnostic Criteria
Superficial necrosis of colonic mucosa
Preservation of base of crypts
Have been termed atrophic microcrypts
Necrotic material may form microscopic pseudomembrane
Does not form endoscopic pseudomembrane
Superficial mucosal hemorrhage and edema
Capillary thrombosis frequently prominent Neutrophils in lamina propria and cryptitis may be present
E coli O157:H7 identified by culture More severe in right colon and cecum
Clinically presents with abrupt onset of bloody diarrhea 3-4 days following ingestion
May be associated with hemolytic uremic syndrome or thrombocytopenia purpura
Robert V Rouse MD
Original posting : November 11, 2009
Differential Diagnosis
Colitis due to E coli O157:H7 may be histologically indistinguishable from acute ischemia
Ischemia is usually localized
Clinical correlation and culture is necessary
Pseudomembranous Colitis Enterohemorrhagic E coli Colitis
Endoscopic pseudomembrane
Pseudomembrane only microscopic
Necrotic crypt epithelium erupts into lumen to form pseudomembrane
Entire upper mucosal layer may slough into lumen to form pseudomembrane
Hemorrhage is not prominent
Prominent hemorrhage and capillary thrombosis
C difficile titers elevated
E coli O157:H7 identified by culture
Associated with antibiotic therapy
Not associated with antibiotic therapy
Bibliography
Noffsinger A, Fenoglio-Preiser CM, Maru D, Gilinisky N. Gastrointestinal Diseases, AFIP Atlas of Nontumor Pathology, First Series, Fascicle 5, 2007.
Morandi E, Grassi C, Cellerino P, Massara PP, Corsi F, Trabucchi E. Verocytotoxin-producing Escherichia coli EH 0157:H7 colitis. J Clin Gastroenterol. 2003 Jan;36(1):44-6.
Griffin PM, Olmstead LC, Petras RE. Escherichia coli O157:H7-associated colitis. A clinical and histological study of 11 cases. Gastroenterology. 1990 Jul;99(1):142-9.
