Synonyms: Escherichia
coli O157:H7; Enterohemorrhagic E. coli; EHEC; Shiga toxin producing E. coli
(STEC); Verotoxin producing E. coli (VTEC);
Category:
Gastroenteritis--Noninflammatory*
Agent Type:
Bacteria
Acuity:
Acute-Severe
Latency/Incubation:
1-10 days; usually 3-4 days;
Initial
Symptoms: Bloody diarrhea with abdominal cramping and little or no fever
usually lasting one week;
Precautions:
Contact if diapered or incontinent;
Comments:
Approximately 8% of patients with EHEC develop hemolytic uremic syndrome (HUS),
the major cause of kidney failure in children in the USA . Other complications are bowel ischemia, stroke, and thrombotic
thrombocytopenic purpura (TTP). Cattle are the most important reservoir,
also deer and rabbits. Disease has occurred after consuming undercooked
hamburger, unpasteurized milk, and contaminated apple cider, sprouts,
lettuce, raw spinach, and salami. Transmission has also occurred from
swimming in contaminated pools and lakes and drinking contaminated water.
The disease may spread between children in daycare centers. [CCDM, p. 160-4;
CDC web site] This infection is the most common cause of bloody diarrhea in
the USA, especially when the patient is afebrile. Leukocytosis often accompanies
the onset of HUS. The Shiga toxins that cause HUS can also cause ischemia to
other organs (brain, eyes, and colon). A diagnosis of EHEC should trigger an
outbreak investigation. Antibiotics are contraindicated. [PPID, p. 1224]
Monitor patients with daily CBC, BUN, and creatinine. In most cases diarrhea
resolves in 5-10 days. Patients with no lab abnormalities 3 days after
resolution of diarrhea have low risk of HUS. [www.doh.wa.gov/ehsphl/epidemiology/CD/ci/ehec_060921.doc]
A university outbreak of diarrhea caused by Calicivirus was mistakenly
attributed to EHEC based on false positive tests (EIA rapid assay for Shiga
toxin). [MMWR 50(23), 2001] E. coli O157:H7, salmonella, and shigella are
possible agents of bioterrorism. [www.bt.cdc.gov] Other strains of E. coli
that cause gastroenteritis are enterotoxigenic (See Cholera.);
enteroinvasive (See Shigellosis.); enteropathogenic; and enteroaggregative.
The last two mentioned strains cause infant diarrhea in developing
countries. [CCDM, p. 160-71]
Diagnostic:
Stool culture on special media and confirmed with serological typing; [Current
Consult, p. 1104] Confirm positive EIA tests for Shiga toxin with
culture and serological typing;
Scope:
Global
Signs and
Symptoms: fever, abdominal pain, blood in stool, diarrhea, acute renal
failure (complication);
Common
Syndromes: Acute GI Symptoms Plus Fever; Acute GI Symptoms, No Fever;
Antimicrobic:
No
Vaccine: No
Entry:
Ingest; Swim; Fecal-Oral;
Source:
Food; Meat; Dairy; Edible Plant; Water;
Vector: none
Reservoir:
Cattle; Cats; Deer; Dogs; Human; Horses; Rabbits; Swine; Wild
High-risk
activities: Consume unpasteurized milk/cheese; Eat undercooked meat or
fish; Ingest infectious agents in food/water; Swim in contaminated water
(ingestion);
Warfare:
Victim--water/food release (infectous)
