Helicobacter pylori is a bacterium that can colonize the gastric mucosa. This microorganism is present in the stomach of 95% of people with duodenal ulcer and in about 70% of those suffering from gastric ulcer. There is also a close connection between its presence and the development of gastritis, an inflammation of the gastric mucosa. In addition, in the long term, the infection can promote the development of stomach cancer, increasing the risk by 2-6 times.
What is it
Helicobacter pylori is generally found in the stomachs of two out of three people. Although it is a hostile environment due to its high acidity, this microorganism has found a way to settle and survive. The bacterium is in fact able to produce in abundance an enzyme, urease, which in turn favors the production of ammonia, a substance that neutralizes the natural acid pH, thus reducing the bactericidal action of the gastric environment.
The discovery of Helicobacter pylori is due to two Australian scientists, Robin Warren and Barry Marshall who, in 1983, isolated the bacterium; Until then it was thought that the strongly acidic environment of the stomach was essentially sterile. The two researchers subsequently demonstrated the bacterial origin of diseases such as peptic ulcer disease and gastritis, a discovery that earned them the Nobel Prize in Medicine in 2005.
Helicobacter pylori has a characteristic spiral shape: the term “Helicobacter” means “spiral-shaped bacterium”, while “pylori” indicates the site where the infection develops most easily, namely at the level of the pylorus, the point of passage between the stomach and the intestine.
The presence of Helicobacter pylori in the gastric tract does not always cause clinical consequences. In most people the infection does not cause symptoms and becomes dangerous to health only when, in conditions of immune imbalance, the metabolic waste of this bacterium causes cellular damage, especially to the gastric walls in the form of ulcers or gastritis.
How Helicobacter pylori infection is contracted
Helicobacter pylori usually colonizes the gastric mucosa in childhood through the consumption of contaminated food or drink. A classic contagion situation is linked to the consumption of the first baby food from the spoon, which the mother may have tasted to check the temperature. In practice, it is the mother who transmits the infection to the baby in the first years of life. The fact that the bacterium is found both in faecal secretions and in saliva and that the infection is considerably more widespread in developing countries where sanitation conditions are worse, also supports the possibility that the bacterium can spread from individual to individual or through the intake of water and contaminated food or handled with hands that are not well cleaned.
Once in the body, Helicobacter creeps under the mucosa that covers the stomach and remains there for years without giving symptoms, and then awakens suddenly, perhaps after a period of stress, as soon as the immune defenses are lowered.
Symptoms
In most cases the invasion of the gastric mucosa by Helicobacter pylori does not cause symptoms. Other times it is responsible for a wide range of ailments. The symptoms that typically make you suspect infection are:
- heartburn that is accentuated after meals
- nausea
- swollen belly
- pain in the pit of the stomach
- belching
- feeling of heaviness and not having digested
- drowsiness after meals
- sense of fullness even after a light meal
- weight loss
- blood loss with feces.
These symptoms could be caused by gastritis or the formation of ulcers in the stomach and duodenum.
Diseases associated with Helicobacter pylori
Helicobacter pylori infection can give rise to various pathologies. Let’s find out together.
Gastric ulcer
Gastric ulcer is a kind of open wound that develops on the inner mucosa of the stomach. If neglected, it can progress to a precancerous lesion that can in turn turn turn into a stomach cancer.
In most cases it is due to the presence of Helicobacter pylori. This germ is found in the stomach of 70% of people with gastric ulcers. Other factors that can promote the development of ulcers include nonsteroidal anti-inflammatory drugs (frequently used to combat headaches and pain), stress and certain foods that, in susceptible individuals, can irritate the stomach, such as concentrated meat broths, aged cheeses, shellfish, pepper, chili, alcohol, chocolate and citrus fruits.
Duodenal ulcer
Duodenal ulcer occurs in the first part of the intestine (duodenum) and is 4 to 10 times more common than gastric ulcer. In most cases it is associated with Helicobacter pylori infection.
If ulcers are treated with antacids, they typically recur when treatment is stopped, while eradicating Helicobacter pylori many patients recover permanently.
Stomach cancer (gastric adenocarcinoma) is often associated with Helicobacter pylori infection and the presence of this bacterium results in an up to 6-fold increase in the risk of developing it.
Another gastric cancer, low-grade malignant lymphoma, is also associated with the presence of Helicobacter in about 90% of cases.
In people with chronic dyspepsia (poor digestion) who do not have a peptic ulcer, the role of Helicobacter pylori is not well understood. However, if the presence of this bacterium is highlighted, a course of therapy to eradicate it should be considered. In some patients immediate results are obtained after therapy, in others there is a gradual improvement over a few months.
Diagnosis
If you suspect Helicobacter pylori infection, you can undergo two types of tests: the so-called breath test or a stool test.
The breath test analyzes the air blown by the patient into a test tube. In practice, radioactively labeled urea is administered to the patient: if the bacterium is present, the urease enzyme produced by it splits urea into ammonium and carbon dioxide, which will be radioactively labeled. The test specifically measures the amount of carbon dioxide emitted with exhalation and has a sensitivity and specificity of 94-98%.
The stool test involves the search for the fecal antigen of this bacterium. Its presence in the stool indicates that the infection is in progress.
In some cases the doctor may prescribe the more invasive gastroscopy. During the examination, samples (biopsies) of the mucous membrane of the stomach and duodenum are taken, then analyzed under a microscope in search of the bacterium. Gastroscopy is the optimal examination if an ulcer is suspected. It is generally recommended for subjects:
- over 50 years of age for the greatest risk, in this age group, of stomach cancer
- under 40-45 years of age when taking nonsteroidal anti-inflammatory drugs
- with symptoms attributable to infection despite having already been subjected to targeted therapy to eradicate Helicobacter pylori.
Treatment
Once the presence of Helicobacter pylori has been ascertained, a targeted treatment must be undertaken to eliminate it or, more correctly, eradicate it.
The therapy is based on antibiotics to be taken for 7-10 days. In general, amoxicillin and clarithromycin are taken in the first instance, which is associated, for a period of about 3 weeks, with the intake of gastroprotector of the proton pump inhibitor family which is used to improve symptoms and treat inflammation of the gastric mucosa.
However, treatment regimens may vary depending on the mechanisms of antibiotic resistance that can be established. When first-line therapy fails, an alternative treatment defined as sequential is switched: five days with amoxicillin and a proton pump inhibitor, followed by five days of therapy with clarithromycin, metronidazole and pump inhibitor.
Unfortunately, in recent years this approach has also begun to lose effectiveness due to the lack of response to clarithromycin and metronidazole. In particular, resistance to clarithromycin has more than doubled since 1998, from one in ten cases to over 20%.
Recently, a new therapy has been introduced with a triple fixed combination capsule containing tetracycline, metronidazole and bismuth, which is always associated with a proton pump inhibitor. This bismuth therapy has been recommended by international guidelines for the treatment of Helicobacter pylori infection in areas of high and low resistance to clarithromycin and by recent Italian guidelines also at the forefront of Helicobacter pylori treatment.
In all cases, at the end of the treatment it is necessary to check if the bacterium has been eradicated with a breath test or with the search for fecal antigen.
If the micro-organism has not been eliminated, the entire cycle should be repeated with different drugs.
Recent treatment regimens have a very high efficacy rate. As a general rule, however, it is always advisable that the most appropriate therapy is prescribed by the specialist in order to avoid the improper use of antibiotics (which contributes to the phenomenon of resistance) and the self-prescription of proton pump inhibitors, which alleviate the symptoms, but risk masking the infection and delaying the diagnosis.
The eradication of Helicobacter pylori has an additional advantage: it halves the risk of getting stomach cancer. This was recently demonstrated by a study, published in the New England Journal of Medicine, conducted on people with the infection and family history of stomach cancer, that is, with a close relative diagnosed with the disease.
Joycelyn Elders is the author and creator of EmpowerEssence, a health and wellness blog. Elders is a respected public health advocate and pediatrician dedicated to promoting general health and well-being.
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