Escherichia coli is by far one of the most popular bacteria worldwide. It is known by many patients, at least by name, and it is one of the most frequent causes of bacterial infections. Ironically, it is a normal bacteria in our gut microbiota, but there are 6 different varieties of E. coli that may cause severe infections in the gastrointestinal tract as well. That is why E. coli can be subdivided into enterotoxigenic, enteropathogenic, enteroinvasive, enterohemorrhagic, enteroaggregative, and enteroadherent E. coli. It is one of the most frequent causes of urinary infections in women, bacterial meningitis in neonates, and intra-abdominal infections in patients with abscesses, intestinal obstructions, and other causes of intestinal perforation.
According to data in the United States, E. coli causes 50% of infections in the urinary tract and 4% of the total cases of diarrhea. However, it causes up to 45% of cases of traveler’s diarrhea, so it is both an important infectious agent for the gastrointestinal tract and the urinary tract. In this article, we are going to cover the signs and symptoms of E. coli infections in both systems and mention the most important symptoms to detect neonatal meningitis caused by E. coli.
The most important signs and symptoms to take into consideration are as follows:
E. coli enteric infections
1. Diarrhea
All E. coli infections in the gastrointestinal tract feature diarrhea as one of the leading signs. It is actually the one that makes patients consult with their doctor because otherwise, the infection might be difficult to diagnose. Diarrhea in E. coli is by far the most important sign and depending on the type of diarrhea and the pattern, you might be able to suspect which strain of E. coli is affecting you.
Enterotoxigenic and enteroaggregative E. coli are both associated with traveler’s diarrhea. They usually appear in people coming from abroad, especially after traveling to tropical countries. It is watery diarrhea with no traces of blood and should be differentiated with rotavirus infections and other causes. In children, enteroadherent, enteropathogenic, and enteroaggregative E. coli are the most important causes of non-bloody watery diarrhea.
These patients often suffer from dehydration, and may even have electrolyte imbalances, which is why it is important to keep hydrated, and it is possible your doctor recommends fluid therapy along with the first dose of intravenous antibiotics.
2. Blood in the stools
Bloody diarrhea is usually called dysentery, and it is important to differentiate whether it is caused by E. coli, Shigellosis, or amebae. When bloody diarrhea is caused by E. coli, the type of strains usually associated with this problem is either enteroinvasive or enterohemorrhagic E. coli. They cause a severe inflammatory response in the gastrointestinal tract, and the lab would also report a high leukocyte count in the stools. These patients typically display fever as well, and they are often dehydrated.
3. Abdominal pain
This symptom is quite common in almost any infection of the gastrointestinal system, and it appears in E. coli infections as well. It is very important to detect the real cause of abdominal pain because there are surgical and non-surgical causes. In most cases, surgical abdominal pain has a sudden onset, and it is very intense. Conversely, E. coli-associated abdominal pain is often caused by stomach cramps. It is a colic pain that might go along with bloating and other gastrointestinal symptoms. Moreover, diarrhea in the event of E. coli enteric infections will give your doctor the ultimate clue, and after examining your stools, your doctor will have data about the type of E. coli strain that is causing the problem and how to manage the infection.
4. Hemolysis and uremia
Hemolysis is the clinical name of red blood cell death in the bloodstream, and uremia is the clinical name of a high level or urea in the blood. These health problems are caused by enterohemorrhagic E. coli, and it is called uremic syndrome, and it is caused by a toxin in this strain of E. coli that destroy blood cells and the wall of the blood vessels. These patients ultimately need to perform dialysis to get rid of the excess urea in the blood, and this uremic syndrome may or may not be accompanied with problems in the central nervous system because the toxin in E. coli has a special destructive effect in the blood vessels of the brain and kidneys.
5. Low platelet count and anemia
Patients with a uremic syndrome may also have low platelet count and anemia because the E. coli toxins affect many other cell lines in the blood, including platelets. They have an important role in blood clotting and wound healing, which adds up to the fact that E. coli enterohemorrhagic breaks down the mucosa of the intestines and destroys the intestinal wall. That is why these patients have dysenteric diarrhea with continuous bleeding, and this adds up to their susceptibility to anemia and dehydration. Altogether, they contribute to making patients feel weak and drowsy, with general malaise, muscle cramps and low energy levels.
E. coli urinary infections
6. Urgency to urinate and frequent urination
It is the most frequent symptom in patients with urinary infections. In E. coli, this is caused by an irritation of the urinary tract and inflammation of the urinary bladder. In this case, the patient becomes unable to hold his or her urine for very long, and they need to go to the bathroom several times, sometimes waking up in the middle of the night to do so. In males with these symptoms, it is important to differentiate urinary infections with prostatitis, which may also be caused by an E. coli infection. In prostatitis caused by E. coli, patients have a swollen and hot prostate to the touch and may develop a prostatic abscess with fever and chills.
7. Burning pain when urinating
It is clinically named dysuria, and it is caused by an irritation of the urinary tract and the acidity of the passing urine activating nerve terminals on its way to be eliminated. In E. coli acute urinary infections, we usually have what doctors call a urethral syndrome. A syndrome is a combination of signs that usually narrows down the search for a diagnosis to fewer medical entities. The urethral syndrome has two leading signs: dysuria (or burning pain when urinating) along with fever. This burning pain is not likely associated with visible blood in the urine. When this happens, it is typically caused by a secondary infection in patients with kidney stones.
8. Low-grade fever
Urinary tract infections due to E. coli is usually associated with a urethral syndrome featuring two main symptoms: fever and dysuria. Fever in acute urinary infections caused by E. coli is typically low and not associated with chills and shivers. However, some patients may not experience this disease the same way, especially if they have coinfection with other bacteria, and if the infection in the urinary tract is starting to become a major problem.
9. Flank pain and high fever
When a lower urinary tract infection progresses, it may extend to the upper urinary tract and reach the kidney. In this case, it is no longer called cystitis but pyelonephritis. Another way E. coli can take to reach the kidneys is through the bloodstream, but it is less likely. When a urinary infection is severe enough to cause pyelonephritis, the most important symptoms to take in consideration are flank pain and high fever.
Flank pain results from inflammation in the kidneys and the surrounding tissue, which makes the organ more susceptible to activate pain nerve terminals. It is usually a dull pain and may be felt as back pain instead of flank pain, but usually made worse when your doctor performs a maneuver in a physical exam. Fever is usually higher than 102°F and may be associated with other symptoms such as headache and nausea.
E Coli meningitis
10. Neonate jaundice
Neonate jaundice is a clear indicative that something is wrong in your baby, and it is probably caused by destruction of red blood cells as a result of toxins or antibodies against their blood type. Certain strains of E. coli might cause severe blood cell destruction problems resulting in jaundice. This is an important symptom to report in young patients and it is recommended to do it as soon as possible.
11. Irritability and feeding problems
One of the leading symptoms in neonates is irritability and decreased feeding. Even in the absence of fever, babies who suddenly stop feeding and stop gaining weight should be monitored by a professional as soon as possible. Meningitis might be one of the diseases to rule out, and it is quite common in E. coli meningitis. In some cases, children might be lethargic and drowsy instead of irritable, and this is more common in patients younger than one month. So, any uncommon behavior or change in the level of activity in your baby should be reported to your doctor right away.
12. Vomiting
All patients with meningitis display nausea and vomiting, and it is usually a projectile vomiting, one that is intense and explosive. This symptom might be a strong indicative of E. coli meningitis when associated with neck rigidity, which is more common in babies older than 4 months.
13. Tense fontanelles
Babies older than 4 months may also have tense or bulging fontanelles. These are soft spots located at the top of the baby’s head. It is normally a bit depressed, and you don’t feel much resistance when gently feeling this spot. When it feels tense or has a visible bulging, it is indicative of meningitis and should be attended by your doctor as soon as possible.
14. Neonate fever
Newborns with E. coli meningitis often have fever as one of the leading symptoms along with jaundice. This symptom is also found in babies one month and 4 months old. It is caused by an inflammatory reaction against the bacteria in the central nervous system with the upcoming activation of the temperature centers in the brain. It is a leading sign, but it is not meaningful by itself because it may be caused by an infection in almost any other part of the body. Thus, it is important to look over the rest of the signs and symptoms to get a clear picture of what is happening. This is why neonates with jaundice or fever are maintained under critical care for a long time until their symptoms have finally improved.
There are still other infections associated with E. coli, such as bacteremia and pneumonia. When diagnosing a disease that might be caused by E. coli, doctors need to rule out many different differential diagnoses. In the gastrointestinal tract, for example, it is important to rule out infection by Enterobacter, Proteus, Klebsiella, Pseudomonas, Rotavirus, and even V. cholerae and amebiasis. These infections should be treated with antibiotics, but also require supportive care, which means maintaining the patient hydrated, with constant blood pressure, and sometimes may even involve dialysis, as we have reviewed above.
Certain strains of E. coli might cause an abscess, which always depends on the site of the infection. When that is the case, patients may require a surgical debridement to reduce their risks. It is also important to take care of the patient’s nutrition, especially after an episode of acute diarrhea.
As you can see, there’s no easy way to deal with an E. coli infection. There are two many types of infection, many subtypes of E. coli to take in consideration, and sometimes therapy will require urgent medical attention and even hospitalization. Therefore, do not delay your diagnosis if you think there’s a possible infection with the symptoms we have mentioned throughout this article.
References
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