Escherichia coli infections

[Kit]

Escherichia coli (E. coli) are a group of gram-negative bacteria that normally reside in the intestine of healthy people, but some strains can cause infection in the digestive tract, urinary tract, or many other parts of the body.

People develop intestinal E. coli infections by eating contaminated food, touching infected animals, or swallowing contaminated water in a pool.
Intestinal infections can cause diarrhea, sometimes severe or bloody, and abdominal pain.
Antibiotics can effectively treat E. coli infections outside the digestive tract and most intestinal infections but are not used to treat intestinal infections by one strain of these bacteria.

(See also Overview of Bacteria.)
Some strains of E. coli normally inhabit the digestive tract of healthy people. However, some strains of E. coli have acquired genes that enable them to cause infection.
The most common infections due to E. coli are in the following:

Digestive tract (causing gastroenteritis)
Urinary tract

E. coli is the most common cause of bladder infection in women.
Other infections that can result from E. coli include the followings:

Infection of the prostate gland (prostatitis)
Gallbladder infection
Infections that develop after appendicitis and diverticulitis
Wound infections (including wounds made during surgery)
Infections in pressure sores
Foot infections in people with diabetes
Pneumonia
Meningitis in newborns
Bloodstream infections

Many E. coli infections affecting areas outside the digestive tract develop in people who are debilitated, who are staying in a health care facility, or who have taken antibiotics.
E. coli can cause infections outside the intestine if the intestine is torn or damaged—for example, by an injury or a disorder, such as inflammatory bowel disease. Then, the bacteria may leave the intestine and spread to nearby structures that have no defenses against them or they may enter the bloodstream.
One strain produces a toxin that causes brief watery diarrhea. This disorder (called traveler’s diarrhea) usually occurs in travelers who consume contaminated food or water in areas where water is not adequately purified.

[Agnes]

The gram-negative bacterium Escherichia coli is the most numerous aerobic commensal inhabitant of the large intestine. Certain strains cause diarrhea, and all can cause infection when they invade sterile sites (eg, the urinary tract). Diagnosis is by standard culture techniques. Toxin assays may help identify the cause of diarrhea. Treatment with antibiotics is guided by susceptibility testing.