You need to know about Helicobacter pylori!

The diagnosis of Helicobacter pylori positive during a physical examination makes many people uneasy.

Regarding Helicobacter pylori infection, we have heard many sayings such as "Helicobacter pylori is a type of carcinogen that can cause gastric cancer", "If one person is positive for Helicobacter pylori, the whole family will be infected", and "Eating garlic regularly can prevent Helicobacter pylori infection."

Are these claims true or false? Let us learn more about Helicobacter pylori!

01 Why can Helicobacter pylori survive in the stomach?

Pure gastric juice is a colorless, transparent liquid that contains a large amount of hydrochloric acid and pepsinogen, with a pH as low as 0.9 to 1.5. It creates a strong acid environment for the stomach, which can inhibit and kill almost all common microorganisms that enter the stomach with food. Therefore, for bacteria, the stomach is one of the worst living environments in the human body.

In fact, for a long time, the medical community did not find the existence of microorganisms in the stomach. It was not until Marshall and Warren's pioneering discovery of Helicobacter pylori in the early 1980s that we gradually realized this "exception" that can survive and reproduce in a strong acid environment.

Helicobacter pylori is the only bacterium known to survive in gastric juice for a long time. It is a Gram-negative, spiral, monopolar multi-flagellate bacillus that can secrete urease, which breaks down the urea component in food to produce carbon dioxide and weakly alkaline ammonia to neutralize nearby gastric acid, thereby providing itself with a suitable environment for survival and reproduction.

02 Can Helicobacter pylori be transmitted to family members?

The transmission of Helicobacter pylori conforms to the saying "diseases enter through the mouth". The most common transmission route is oral-oral or fecal-oral, and it can be transmitted from person to person through saliva, tableware, and food.

1. Fecal-oral transmission: If Helicobacter pylori living in feces contaminates water or food, the drinker or eater may be infected with Helicobacter pylori. The transmission is more likely to occur in areas with poor sanitation.

2. Oral transmission: It is transmitted through saliva, such as traditional family gatherings without using serving chopsticks, mouth-to-mouth or chewing feeding, kissing, kissing children's lips, etc.

03 Will infection with Helicobacter pylori definitely lead to stomach cancer?

Helicobacter pylori is a risk factor for a variety of digestive system diseases such as gastritis, gastric ulcer, gastric mucosa-associated lymphoid tissue lymphoma and gastric cancer, and has been listed as a Class I carcinogen by the World Health Organization.

China is a country with a high incidence of Helicobacter pylori infection, with an infection rate of 50%-80%. However, in reality, about 80% of people infected with Helicobacter pylori will only suffer from gastritis, and most people will not have obvious symptoms, or will only experience symptoms such as indigestion and abdominal distension, which are usually only discovered through regular physical examinations.

Only about 1% of patients infected with Helicobacter pylori will develop gastric cancer. However, the low incidence does not mean that we do not need to be vigilant. A survey in China showed that 78.5% of non-cardia gastric cancer cases and 62.1% of cardia cancer cases were mainly caused by Helicobacter pylori infection. Helicobacter pylori parasitizes, reproduces, and destroys the human body for a long time, and gastric mucosal cells may undergo a series of changes: normal gastric mucosa → chronic superficial gastritis → chronic atrophic gastritis → intestinal metaplasia → dysplasia → gastric cancer.

Helicobacter pylori can secrete two toxins: vacuolating toxin-related protein and cytotoxin-related protein. Vacuolating toxin-related protein can cause epithelial cells to fall off from the gastric mucosa, inducing an inflammatory response. If the inflammatory response persists for a long time, chronic gastritis will form. Cytotoxin-related protein will induce apoptosis of a large number of epithelial cells, and the number of cells that can secrete mucus will decrease. This will cause the part of the gastric mucosa that loses mucus protection to be directly exposed to gastric acid, which will be damaged by gastric acid and lead to the formation of gastric ulcers. Severe gastric ulcers can also lead to serious consequences such as gastric perforation and gastric bleeding.

These two toxins will also slowly cause normal gastric mucosal epithelial cells to be replaced by intestinal mucosal epithelial cells (referred to as gastric mucosal intestinal metaplasia, a precancerous lesion). If not treated, it may further develop into gastric cancer.

Therefore, we do not need to be afraid of the word "Helicobacter pylori". The process from Helicobacter pylori infection to gastric cancer may take years or even decades. This slow progression provides an opportunity for early detection and treatment of Helicobacter pylori infection. As long as we intervene and treat at any node and interrupt this process, we can prevent the occurrence of gastric cancer caused by Helicobacter pylori.

Studies have shown that eradication of Helicobacter pylori at any stage of gastritis is beneficial to reduce the incidence of gastric cancer, especially eradication of Helicobacter pylori before precancerous lesions occur can better prevent gastric cancer. So what do we need to know next? What should we do next?

04 How to determine whether you are infected with Helicobacter pylori?

Non-invasive testing methods:

1. C13 and C14-urea breath test: As we said before, Helicobacter pylori can decompose urea into NH3 and CO2, of which CO2 enters the blood circulation after being absorbed in the upper part of the small intestine and is expelled with exhaled air. Taking the C13-urea breath test as an example, we mark the C atom in urea with C13. If the person being tested is infected with Helicobacter pylori, after taking this labeled urea orally, Helicobacter pylori will decompose the urea containing C13 into NH3 and CO2 containing C13, which will be expelled into our exhaled gas. At this time, the person being tested can detect the labeled CO2 by exhaling to a high-precision gas isotope ratio mass harmonic instrument. This test can not only be used to screen people infected with Helicobacter pylori, but also to review patients who have received drug treatment and observe the treatment situation. It should be noted that because C14 is radioactive, couples planning to conceive, pregnant and lactating women, and children under the age of 14 should undergo a more stable and safe C13 test.

2. Serum Helicobacter pylori antibody test: After Helicobacter pylori colonizes the human body, our immune system will form specific antibodies against the antigens on the surface of the bacteria. By extracting the peripheral blood of the examinee and testing whether there is such specific antibody in the serum, it can be determined whether the patient is infected with Helicobacter pylori.

Invasive testing methods:

Digestive endoscopy: If the above non-invasive examination methods are like "blind men touching an elephant", then gastroscopy gives gastroenterologists "eyes" that can see deep into the digestive tract. Gastroscopy can conduct a comprehensive examination of the gastric mucosa and directly observe whether there is inflammation, ulcers, polyps and tumors in the stomach. If abnormalities are found, tissues of suspected lesions can be obtained under direct endoscopy. The removed tissues can not only be tested for Helicobacter pylori infection through rapid urease tests, but also pathological biopsies and cytological examinations can be performed to further clarify the benign or malignant nature of the lesions. Generally, high-risk patients with gastrointestinal symptoms, family history of gastric cancer, and patients who have been tested positive for Helicobacter pylori by other methods can follow the advice of gastroenterologists in regular medical institutions and undergo digestive endoscopy.

05 How to prevent Helicobacter pylori infection in daily life?

1. In order to prevent the spread of the virus among family and friends, it is recommended to use separate dining and public spoons and chopsticks when eating. Tableware at home can be disinfected regularly (boiling or in a disinfection cabinet) to avoid sharing food with each other and mixing tableware and water cups.

2. Develop a good habit of washing hands before and after meals, learn the correct "hand washing posture", and avoid eating street food.

3. Add Helicobacter pylori testing to regular physical examinations. People who often have bad breath, stomach discomfort, acid reflux and bloating, or have a family history of digestive system tumors should pay more attention to digestive tract related examinations.

4. Infants and young children are susceptible to Helicobacter pylori and should avoid mouth-to-mouth feeding and chewing feeding.

5. Pay attention to food hygiene and avoid drinking unclean water and food.