1 Diagnostic Points

(1) Diagnostic Points

(1) Based on the course of the disease, clinical symptoms, and physical signs, and after excluding other causes of chronic upper abdominal pain, most patients can be clinically diagnosed.

Patients with chronic gastritis generally experience upper abdominal fullness (especially after meals), upper abdominal pain (irregular in nature), belching, nausea, and decreased appetite, without any particularly distinctive symptoms. Recent studies have found that gastritis in the gastric body tends to have fewer gastrointestinal symptoms, but may manifest obvious loss of appetite, reduced food intake, accompanied by weight loss, emaciation, and anemia (mostly iron-deficiency anemia, with a small number possibly developing pernicious anemia); gastritis in the gastric antrum, on the other hand, shows more pronounced gastrointestinal symptoms, especially in patients with frequent bile reflux or gallstones, mainly including abdominal distension (most noticeable after meals), a heavy feeling in the stomach, frequent belching, dull or distending pain, some patients experiencing acid regurgitation, nausea, or vomiting, and occasionally even bile vomiting. Stools may be loose or dry, sometimes resembling duodenal ulcers or pre-pyloric ulcers, with occasional minor recurrent bleeding, even hematemesis, possibly due to acute erosion. During physical examination, most patients with chronic gastritis do not show obvious signs; occasionally, mild tenderness in the upper abdomen may be detected, and during active phases of the disease, there may be marked tenderness below the xiphoid process or on the left side of the midline.

(2) Fiber gastroscopy and gastric mucosal biopsy are the only means of confirming the diagnosis of chronic gastritis and classifying it.

① Diagnostic criteria for superficial gastritis via gastroscopy: Lesions are often most evident in the gastric antrum, mostly diffuse (though localized lesions can also occur), with the surface of the gastric mucosa showing alternating red and white or mottled changes, sometimes with scattered erosions, often accompanied by grayish-white or yellowish-white exudates. Pathological examination of biopsy specimens indicates that superficial inflammatory glands remain intact and are not reduced. ② Diagnostic criteria for atrophic gastritis via gastroscopy: The gastric mucosa is mostly pale or grayish-white, with thinning or flattening of the folds, and submucosal vessels are clearly visible, appearing purplish-blue; however, the color of the mucosa is often influenced by overall hemoglobin levels, meaning that when the body suffers from severe anemia, insufficient blood supply to the gastric mucosa makes it appear pale. Lesions may be diffuse or mainly confined to the gastric antrum. Pathological examination of biopsy specimens reveals that original glands have atrophied; if the reduction is within one-third, it is considered mild; if it is between one-third and two-thirds, it is moderate; if it exceeds two-thirds, it is severe. Intestinal metaplasia or pyloric gland metaplasia (also graded as mild, moderate, or severe) may or may not be present in some cases; dysplasia (or atypical hyperplasia), characterized by nuclei of various shapes, deeper staining, disordered arrangement, and pseudostratified appearance, may also be present or absent.

(3) When conditions permit, the following auxiliary examinations can also be performed. ① Gastric juice analysis: Measures basal gastric acid secretion, maximum gastric acid secretion, and pH value. Superficial gastritis usually shows normal or slightly low values, while chronic atrophic gastritis, especially if the main lesion is in the gastric body, often exhibits significantly reduced gastric acid secretion, and may even show no gastric acid at all, because the parietal cells responsible for secreting gastric acid are mainly distributed in the gastric body. ② Serum gastrin measurement: Normal range is 30–140 pg/ml. Type A atrophic gastritis often shows elevated levels, while Type B may remain within the normal range or decrease. ③ Serum parietal cell antibody measurement: Type A atrophic gastritis often tests positive, while Type B tests negative. ④ Helicobacter pylori (HP) testing: Collect gastric mucosa for urease test, direct smear, or bacterial culture. ⑤ Gastrointestinal X-ray barium meal examination usually shows no abnormalities. In atrophic gastritis, the gastric body mucosa may appear thinned or even disappeared, and the gastric fundus may be smooth with no mucosal patterns.