In chronic gastritis, several manifestations can be distinguished, which have correspondingly different causes. Here we present all types of gastritis and explain what each diagnosis looks like.
Chronic gastritis: type A gastritis.
Type A gastritis is an autoimmune disease. In this case, so-called autoantibodies are formed against the gastric acid-producing cells of the gastric mucosa (occupant cells). The gastric mucosal cells produce gastric acid, which is essential for digestion. At the same time, they produce the so-called intrinsic factor. Only with this intrinsic factor is the absorption of vitamin B12 from the intestine possible. Autoantibodies directed against the occupant cells thus prevent both the production of gastric acid and the absorption of vitamin B12. The consequences of type A gastritis are decreased stomach acid (achlorhydria) and anemia as a result of vitamin B12 deficiency. Vitamin B12 is mandatory for the formation of blood pigment. This form of gastritis is relatively rare, accounting for about five percent of cases. However, autoimmune gastritis can be associated with other autoimmune diseases. Autoimmune gastritis also promotes the development of stomach cancer.
Chronic gastritis: type B gastritis.
At circa 85 percent, the most common cause of chronic bacterial gastritis is infection with the pathogen Helicobacter pylori. More than half of the world’s population carry the Helicobacter pylori pathogen in their gastric mucosa. It is a bacterium that produces enzymes involved in cellular damage of the gastric mucosa. This pathogen can survive in acidic gastric juice and pass through the mucosal wall by certain mechanisms. The source of infection is unclear. However, it has been shown that this pathogen can be transmitted from mother to child during pregnancy. Now that the causative agent of gastritis is known, gastritis can be treated with antibiotics like any other inflammation caused by bacteria.
Chronic gastritis: type C gastritis.
Like type A gastritis, this form of gastritis also occurs relatively rarely. Only about 10 percent of patients with gastritis have type C gastritis. In this form of gastritis, bile juices mistakenly flow into the stomach rather than the small intestine. Reflux of bile juices is especially common after gastric surgery. The bile juices alter the acidic environment of the stomach and attack the protective layer of the mucosa. As a result of this injury, the stomach lining can become inflamed. Certain medications used to treat pain and inflammatory processes, such as acetylsalicylic acid or certain rheumatoid medications, attack the protective layer of the gastric mucosa, triggering damage.
Diagnosis of type A and B gastritis.
Characteristic of the autoimmune gastritis of type A gastritis is the curvature of the mucosa. In type B gastritis, specular examination reveals isolated patchy redness or small nodular mucosal elevations. In Helicobacter pylori gastritis, gastric ulceration (ventricular ulcer) may be present in addition to gastritis. Taking a tissue sample is essential for the rapid urease test. For this purpose, the mucosal sample is placed in a test fluid containing a color indicator and urea. Helicobacter pylori produces the enzyme urease and is able to cleave urea. If Helicobacter pylori is present in the tissue sample, the cleavage of urea will cause the test fluid to turn red. The test result is considered positive if the discoloration has occurred after 24 hours. In case of high bacterial colonization, the discoloration occurs after 15 minutes. Another possibility of diagnosis is the breath test. It is used to detect Helicobacter pylori. Since this examination method can bypass gastroscopy, this test is preferably used in children. However, it is not possible to assess the gastric mucosa with the breath test.
Diagnosis of type C gastritis
In type C gastritis, the gastric mucosa is swollen and covered with dark spots interspersed with blood. This appearance is mainly found in inflammation caused by pain medications.If the disease is already far advanced, even touching these areas with the endoscope can trigger bleeding. If gastritis is known, this includes the so-called shilling test. In this test, the patient is given radioactive labeled vitamin B12 to swallow. As already described, vitamin B12 can only be absorbed in the presence of intrinsic factor in the tail of the small intestine. If autoimmune gastritis is present, the vestibular cells are unable to release intrinsic factor. As a result, vitamin B12 cannot be absorbed. The result is a reduction in vitamin B12 excretion in the urine. In the second step of the Schilling test, the radioactive vitamin B12 and the intrinsic factor are administered to the patient simultaneously. If the radioactive vitamin B12 is detected in the urine, this is confirmation of autoimmune gastritis resulting in pernicious anemia (vitamin B12 anemia). In addition, blood is drawn to detect possible anemia. The anemia may be the result of bleeding of the gastric mucosa or vitamin B12 deficiency. It is also recommended to determine antibodies against the gastric mucosa’s occupant cells to detect autoimmune gastritis (type A gastritis).
Complications of gastritis
Autoimmune gastritis promotes the development of gastric cancer. Furthermore, severe bleeding from the gastric mucosa may occur. As a result, chronic anemia with fatigue, lassitude, listlessness, etc. may occur. In the worst case, gastric bleeding can lead to circulatory shock. In this situation, the bleeding must be stopped immediately via gastroscopy. If this is not successful, the affected person may bleed to death. Another possible complication is the development of gastric or duodenal ulcers (ventricular ulcer and duodenal ulcer). Both types of ulcer are characterized by cramping, pressing, pinching or stabbing pain in the upper abdomen. In the case of gastric ulcer, the pain and the feeling of pressure usually occur shortly after eating, whereas in the case of duodenal ulcer, the pain occurs mainly on an empty stomach. After eating, the pain disappears for a few hours. However, this does not always have to be the case. Pain during the night is also common. In some ulcer patients, these typical symptoms are absent; there are only uncharacteristic digestive complaints, belching and heartburn, and sometimes nausea with vomiting.
