9 infections caused by E. coli

Many people are of the belief that the only disease caused by E. coli, short for Escherichia coli, is gastroenteritis. This belief is fueled by frequent reports in the media, of E. coli outbreaks associated with various contaminated foods. However, E. coli is actually found naturally in our bodies, in the intestines. It is the most common bacteria found in the human gastrointestinal tract.

There are many different types, or strains, of E. coli. Some strains reside in the gut of other animals such as cattle and goats. Specific strains of E. coli are associated with specific illnesses. However, E. coli can cause infection anywhere in the body.

Below, in random order, are 9 examples of infections caused by E. coli.

1. Pneumonia – possible in anyone, but usually seen in patients who are chronically ill, such as stroke patients who are bedbound and unable to properly control their mouth/throat secretions. E. coli pneumonia is also seen commonly in patients in the ICU who are hooked up to the ventilator. Essentially, E. coli present in the mouth or throat, makes it’s way down into the lungs, and invades the tissues, causing pneumonia

2. Urinary tract infection (UTI) – E. coli is the most common bacteria causing UTIs. Because of the proximity of the urinary tract to the gastrointestinal tract, it is easy for E. coli to cause UTIs. See this post and this post for more detailed explanations of how UTIs arise.

3. Meningitis – this refers to an infection of the membranes covering the brain. E. coli is an uncommon cause of meningitis. When it does occur, it is seen mostly in newborn babies, or in persons who recently had neurosurgery. Babies would have acquired E. coli while passing through the birth canal. If they are premature, or have some other reason for a weaker than expected immune system, the E. coli can invade the baby and cause infections such as meningitis.

For patients who recently had neurosurgery, often there are drainage tubes leading out of the brain. Any foreign device serves as an entry point for germs, including E. coli.

4. Cellulitis – this refers to an infection of the skin and underlying tissues. E. coli commonly infects chronic ulcers that patients may have, such as bed sores, and diabetic foot ulcers. It can invade the ulcer and spread to surrounding skin and tissues, causing cellulitis. Cellulitis is characterized by redness, warmth, pain and swelling of the affected area.

5. Liver abscess – E. coli can escape through the bowel wall, into the blood stream, then ‘travel’ to the liver, where it may ‘lodge.’ If, for whatever reason, the body’s immune system fails to eradicate the E. coli from the liver, it remains there and multiplies. Eventually an abscess forms in the liver. This is not an uncommon scenario. Sometimes it is seen as a delayed complication of appendicitis, or some other intra-abdominal infection.

6. Surgical wound infection – A surgical incision results in a breech in the integrity of the skin. Any defect in integrity of the body, is more prone to infection, compared to intact, normal tissues. Any surgical wound may become contaminated and then infected with E. coli. However there is a higher chance with abdominal incisions for bowel surgery. E. coli-containing fecal material can contaminate the wound and give rise to infection.

7. Gastroenteritis – this is the E. coli infection everyone is aware of, and is caused by ingestion of contaminated food or water. The E. coli in this case is either a toxin producing strain, or a strain that causes direct damage to the lining of the intestines. The result is irritation of the intestinal walls, causing increased secretions and therefore watery diarrhea.

8. Endocarditis – this refers to an infection of a heart valve. Endocarditis from E. coli is rare. When it occurs, it is usually in a patient with other medical problems, particularly those who have catheters in their large veins for prolonged periods, such as dialysis patients or cancer patients with Mediports.

Frequent manipulation of these catheters for dialysis or chemotherapy, increases the chance of contamination over time. If the line gets infected with E. coli, the bacteria gets into the bloodstream, and can ‘stick’ onto one of the heart valves, especially if it is already damaged, causing infection.

9. Osteomyelitis – this refers to an infection of bone. As with cellulitis, infection can spread from an infected ulcer to the underlying bone. This is commonly seen with diabetic foot ulcers or with bedsores in bed-bound patients. Bone infection can also occur if there was E. coli infection of the blood stream. From the blood, the E. coli then lodges onto bone in some region of the body where there was some abnormality, particularly areas with arthritis such as the knee, or the lower spine.

So there you have it – 9 infections that can be caused by E. coli. And there are many others. People can get ear infections, eye infections, sinus infections, etc. etc. from E. coli. So if you, unfortunately, receive an E. coli infection diagnosis from your doctor, you don’t need to be stunned, trying to figure out how E. coli from your beef steak, got into your foot.