Not Just a Stomach Bug: All About E. coli Infections

You might think E. coli is only a concern after a questionable meal, but the truth is, it can sneak into your life in unexpected ways. From a seemingly harmless salad to unnoticed lapses in hygiene, this bacterium can enter your body to cause various infections. 

It’s the leading cause of urine and stomach infections and can even lead to more severe complications if not addressed in time. So, how can a common bacterium turn your world upside down? Let’s find out.

E. Coli (Escherichia coli) is a type of bacteria usually found in the intestines of humans and animals. Most strains are harmless and play a role in digestion. However, certain strains of E. coli can cause infections when they spread outside the intestines.

E. coli is not a singular type of bacterium with just one effect. Instead, there are multiple strains, each capable of causing various infections based on their specific characteristics. While some E. coli strains primarily cause gastrointestinal (GI) infections, others are notorious for causing urinary tract infections (UTIs). Here’s a detailed look at the main types:

Certain E. coli strains are known for causing GI infections, commonly resulting in diarrhoea, abdominal pain, and nausea. These strains are usually acquired through contaminated food or water. 

• Enterotoxigenic E. coli (ETEC)
  Known for causing traveller's diarrhoea, this strain affects millions yearly, especially in developing countries. It produces toxins that irritate the intestines, leading to watery diarrhoea and excessive fluid secretion.
• Shiga Toxin-Producing E. coli (STEC) / Enterohemorrhagic E. coli (EHEC)
  This strain, particularly E. coli O157, produces potent Shiga toxins that damage the intestinal lining. This can cause severe complications like hemolytic uremic syndrome (HUS), which can lead to kidney failure.
• Enteropathogenic E. coli (EPEC)
  EPEC is a common cause of severe diarrhoea in infants and young children. It attaches to and damages the cells lining the intestines, leading to inflammation and water loss.
• Enteroaggregative E. coli (EAEC)
  EAEC adheres to the intestinal lining and forms biofilms, causing prolonged inflammation. This results in persistent diarrhoea, especially in children and immunocompromised individuals.
• Enteroinvasive E. coli (EIEC)
  EIEC behaves similarly to Shigella bacteria, invading and destroying the intestinal lining cells, resulting in symptoms resembling dysentery.

• Stomach Cramps: Abdominal pain or discomfort is common, often associated with bloating or gas.
• Diarrhoea: Can range from mild to severe, and in some cases, may be bloody due to toxin-producing strains like E. coli O157.
• Nausea and Vomiting: Feeling queasy or vomiting may accompany the diarrhoea.
• Fever: Mild to moderate fever can occur as the body responds to the infection.
• Dehydration: Due to the loss of fluids from diarrhoea and vomiting, symptoms like dry mouth, dizziness, or reduced urine output may occur.

An Indian population-based study reveals that E. coli was the most prevalent pathogen identified in UTI infections, appearing in 55.0% of microbial cultures. But how does this gut-dwelling bacterium find its way into the urinary tract? It turns out that certain habits and practices make it easier for E. coli to travel from the rectal area to the urethra. Poor hygiene, sexual activity, and certain contraceptives can all play a role. Once inside, it can multiply rapidly in the bladder, causing infection. A specific strain of E. coli, uropathogenic E. coli (UPEC), is the main culprit for UTIs. This strain can ascend from the urethra to the bladder and, in severe cases, reach the kidneys.

Most E. coli infections occur when the bacteria enter the urinary tract. Here are common causes and risk factors:

• Shorter Urethra: Women are more prone to UTIs due to their shorter urethra, which gives bacteria a quicker route to the bladder.
• Poor Hygiene: For women, wiping from back to front after using the toilet can introduce E. coli from the anal area to the urethra. It’s recommended to always wipe from front to back to reduce this risk.
• Sexual Activity: During sex, bacteria from the genital or anal area can be pushed into the urethra. This is more common in women due to the proximity of the urethra to the vaginal and anal areas. 
• Certain Contraceptives: Spermicides and non-lubricated condoms can cause urethral irritation. This irritation can weaken the body’s natural defences, making it easier for bacteria to cause an infection.

Additional risk factors include being immobile for long periods, not drinking enough fluids, and pregnancy.

When E. coli infects the urinary tract, it leads to specific symptoms, such as:

• Frequent Urination: Feeling the need to urinate more often than usual.
• Burning Sensation: Pain or discomfort while urinating.
• Abdominal Pain: Cramps or pain in the central lower abdomen.
• Cloudy or Blood-Tinged Urine: Indicating the presence of bacteria or blood.
• Fever and Chills: Symptoms that may indicate a urinary tract  infection.

Different strains can lead to various infections, some of which are quite serious.

• Sepsis
  When E. coli enters the bloodstream, it can trigger sepsis — a dangerous, widespread infection and inflammatory response that can be life-threatening. This is especially risky for infants, the elderly, and those with weakened immune systems. Symptoms may include fever, rapid heart rate, and confusion.
• Prostatitis in Men
  If E. coli infects the prostate gland, it can lead to prostatitis, an inflammation that causes symptoms like difficulty urinating, pain in the lower back or pelvis, and fever. Prostatitis requires treatment to alleviate symptoms and prevent further complications.
• Pelvic Inflammatory Disease (PID) in Women
  E. coli can cause Pelvic Inflammatory Disease (PID) in women, which affects the reproductive organs. Women with PID may experience lower abdominal pain, fever, and unusual vaginal discharge. Left untreated, PID can lead to long-term complications, including infertility.
• Gallbladder Infections
  E. coli sometimes infects the gallbladder, causing severe upper-right abdominal pain, fever, and jaundice. Prompt treatment is necessary to avoid complications.
• Wound infections
  Open wounds exposed to contaminated environments can be infected by E. coli, leading to redness, swelling, and pain at the wound site.
• Pneumonia and Meningitis
  Though uncommon, E. coli can cause pneumonia or meningitis, especially in newborns or people with compromised immunity.

If left untreated: 

• A UTI can spread from the bladder to the kidneys, causing severe pain, fever, and even kidney damage.
• Hemolytic Uremic Syndrome (HUS), caused by Shiga toxin-producing E. coli, can lead to kidney failure. The Shiga toxins produced by E. coli damage the tiny blood vessels in the kidneys. This causes red blood cells to break down and form clots in the kidneys' small blood vessels, disrupting the kidney’s ability to filter blood and leading to acute kidney failure.

The onset of symptoms of E. coli infection depends on the strain. Shiga toxin-producing E. coli (STEC) typically causes symptoms within three to five days of exposure. Other strains may trigger symptoms within hours or take up to 10 days to show signs of infection.

Healthcare providers use specific tests based on the suspected infection:

• Stool Tests: To identify E. coli strains causing digestive issues.
• Urine Culture: To confirm E. coli in UTIs.
• Blood Culture: To check for bloodstream infections.
• Spinal Tap: To diagnose rare cases of bacterial meningitis due to E. coli.

• Cook Meat Thoroughly: Ensure meat reaches safe temperatures.
• Avoid Cross-Contamination: Keep raw meats separate and clean surfaces properly.
• Wash Produce: Rinse all fruits and vegetables thoroughly.
• Choose Pasteurised Dairy: Avoid unpasteurised milk and juices.
• Practice Good Hand Hygiene: Wash hands after handling food or using the restroom.

For gastrointestinal (GI) infections, the primary focus is on supportive care, which includes staying hydrated and resting to allow the body to recover.

• Maintain Hygiene: Wipe front to back to prevent bacterial spread.
• Stay Hydrated: Drink adequate water to flush out bacteria.
• Urinate After Sex: This helps clear bacteria from the urethra.
• Avoid Irritants: Steer clear of scented products in intimate areas.
• Consider alternate Birth Control products: Avoid spermicides if prone to UTIs.

“It’s also important to drink adequate fluids. You may be tempted to reduce your fluid intake if urinating is uncomfortable. Urination can help flush the bacteria from your system. Stay hydrated and urinate often while taking your medications,” explains Dr Malav Modi, a urosurgeon in Mumbai.

E. coli infections can range from annoying disruptions to serious health risks, but with the right knowledge, you can keep them from taking control. Recognise the symptoms, practise smart prevention, and trust your gut when something feels off.

The infective stage occurs when harmful strains of E. coli bacteria multiply in the urinary or gastrointestinal tract, causing symptoms like pain or diarrhoea.

Common sources include undercooked ground beef, unpasteurised dairy products, and contaminated vegetables or water.

If you experience symptoms like burning during urination, frequent urination, abdominal pain, or diarrhoea, you may have an E. coli infection and should consult a doctor.

Contaminated water, raw or undercooked meat, and cross-contamination from dirty surfaces or utensils are the primary sources of E. coli.

Severe E. coli infections, particularly those involving the kidneys or bloodstream, can lead to long-term complications like kidney damage or chronic urinary issues.

Mild E. coli infections, like some cases of food poisoning or uncomplicated UTIs, can resolve without treatment in about a week. However, severe symptoms or persistent infections need medical attention to avoid complications.

Yes, E. coli infections can be life-threatening, especially if they lead to sepsis. While the average mortality rate is around 17%, factors like age, pre-existing health conditions, and individual response to treatment can impact the outcome.