What is Helicobacter Pylori and whom does it affect?

What is Helicobacter Pylori and whom does it affect?

In this article, we will talk about one of the biggest enemies of gastroenterologists: Helicobacter Pylori has in the human stomach its only known reservoir. The mechanisms of transmission raise doubts; it is considered relevant, in developed countries, the transmission from person to person via the fecal-oral and oral-oral routes. In developing countries, water or food contamination would have more relevance. After reaching the human stomach, Helicobacter Pylori protects itself by creating an alkaline «microclimate» due to urease activity, it moves thanks to its flagella through the mucus layer and it sticks to specific receptors of gastric epithelium, causing a host´s inflammatory response of variable intensity. 

It is a very frequent bacterium in our environment, whose infection relates with the development of chronic gastritis and gastro-duodenal peptic ulcers. It affects to the 50% of world population approximately, being the most frequent bacterial infection. It is considered that actually there are about 3,8 million infected people, being detected in all countries of the world, at any age and no differences between sexes, affecting men or women equally. Infection prevalence changes in different geographic areas widely, according their socioeconomic status and the measures of public health adopted by the different countries. 

How does it transmit?

It is present in saliva, stool and dental plaque. Helicobacter Pylori contagion can occur between people by direct contact with saliva, vomit and especially fecal matter, when the person carrying the virus does not wash his/her hands properly after every bowel movement. It can also happen when someone touches a contaminated object, as a towel, and then puts her/his hands to her/his mouth. Nevertheless, a mechanism of transmission is not known exactly. 

The infection usually occurs in childhood, while it is rare that it occurs in adult age. In developed countries, it generally takes place in the family, between parents and sons or siblings, where there is contact in the form of a kiss and objects are shared frequently. It can also occur between people living in nursing homes and in other places where it is usual the close contact. 

However, in developing countries, it is more common that the contagion occurs through food and water contaminated with stool (fecal-oral route). In any case, the risk of contracting a disease is higher for people who live in crowded or unhealthy conditions, without access to clean and potable water, as well as for whom cohabit with a person who already has the infection. In fact, the prevalence of the infection by this bacterium is close to 80% in less developed nations, according to the Spanish Foundation of Digestive System (FEAD).

The domestic animals are not carriers of the infection so they cannot spread it. The risk of transmit the infection decrease with the improvement of the socioeconomic conditions and hygienic measures. 

What symptoms and diseases does it produce?

  • Swelling, burning or pain in the abdomen after meals.
  • Loss of appetite and weight.
  • Belching, nausea and vomits.

The called erosive gastritis: which consists of the wear or thinning of the mucosal layer that line the inside of the stomach.

Gastro-duodenal or peptic ulcer: because Helicobacter Pylori increases the production of acid and toxins inside the stomach and it alters its defenses. This ulcer is a more or less deep sore in the mucosa lining the stomach, and which can manifest with sensation of early satiety when eating, problems to drink the usual quantity of liquid, hungry or feeling of emptiness in the stomach between one and three hours after eating, acidity, mild nauseas, stomachache or pain in the chest and loss of weight. If there is blood in the vomit or stool, it might be a signal that the ulcer has produced a bleeding, or it has perforated or blocked the stomach. In this case, we must solicit medical assistance immediately. 

Finally, though it is very less frequent, the infection of this bacterium can lead to develop some types of gastric cancers. However, we must not be alarmist, since the risk of suffering this disease is very low, even in those who are infected by this bacterium. Nevertheless, in some occasions, taking into account the symptomatology and other patient´s factors, the doctor values the need to perform some exams to discard it. 

In what moment does Helicobacter Pylori usually cause an ulcer?

It is a very frequent bacterium in our environment, which has used to live in the acid climate of the gastric cavity, being located in the most superficial layer of gastric mucosa. It can make the stomach more vulnerable to acid-peptide damage, as it can secrete enzymes and toxins causing an inflammatory reaction that can produce lesions like gastritis and gastro-duodenal ulcer.

The environmental factors that can favor the appearance of ulcers in patients with infections are smoking, alcohol intakes, low socioeconomic status, bad hygienic and nutritional habits and previous pathologies. Ulcers are produced with more frequency in adult age and in patients with previous history of peptide ulcer. 

What tests are realized to detect it?

There are different forms to study the infection. Invasive tests can be used like a gastroscopy with biopsy, which will identify the gem by studying it under a microscope, or with a fast urease test. There are usually used non-invasive tests like the Breath test, detection of Helicobacter Pylori antigens in stool or blood antibodies. Nowadays, the better test is the 13C urea breath test, due to its comfort, high diagnostic capacity and low risk.

What is its treatment?

The treatment is complex and a doctor must always supervise it. Nowadays, the objective that is demanded to the eradication therapies is that its eradicating efficacy will be equal or superior to 90%, which makes essential the optimization of treatments for the infection. For this, it is necessary apply a series of measures such as the selection of more efficient antimicrobials depending of the bacterial resistance rates in the geographic environment in where the treatment for Helicobacter Pylori is applied, increase the number of antimicrobials using quad therapies, extend the duration of treatments during 14 days and use the medicines right doses. It is also necessary to optimize the gastric acid inhibition using inhibitors of the proton bomb in high doses.

There are different lines of treatment with several combinations of drugs during 10 to 14 days. A drug is administrated, which decreases the acid secretion of the stomach (omeprazole, lansoprazole, esomeprazole or similar), with various antibiotics, the most usual are amoxicillin, clarithromycin and metronidazole. In cases of penicillin allergy, bacterial resistance or failure of previous treatment, other antibiotics will be used, such as levofloxacin or tetracycline, associated or not with bismuth. Nowadays, there are pharmaceutical formulations that combine these medicines, making easier their use. 

On the other hand, there are available evidence that proves how the use of probiotics (specifically selected) as treatment aids increases the eradication rates and decreases the side effects of the new eradicators treatments. 

It is essential to ensure proper adherence to prescribed treatments, using for this all the available tools, because if the treatment is not realized in a correct manner, the bacterial resistance can increase and make it even more difficult to eradicate the infection. 

Must we confirm that we have cured the Helicobacter Pylori infection?

Yes, we must; it must be always confirmed the eradication of the bacterium passing at least 1 month after finishing the treatment. If the treatment has been successful, it will be very rare to get the infection again.