Chronic atrophic gastritis

by Jason Wasserman MD PhD FRCPC
December 11, 2024

This article is designed to help you understand your pathology report for chronic atrophic gastritis of the stomach. Each section explains an important aspect of the diagnosis and what it means for you.

What is chronic atrophic gastritis?

Chronic atrophic gastritis is a medical condition where inflammation causes the lining of the stomach to become thin and damaged over time. This thinning primarily affects the glands that produce stomach acid and digestive enzymes, reducing stomach function. This condition is significant because it can interfere with food digestion and nutrient absorption and may increase the risk of stomach cancer.

What are the symptoms of chronic atrophic gastritis?

The symptoms of chronic atrophic gastritis can vary but often include:

• Indigestion or discomfort in the upper abdomen.
• Nausea and occasional vomiting.
• A feeling of fullness after eating only a small amount of food.
• Loss of appetite.
• Weight loss.
• Fatigue.

What causes chronic atrophic gastritis?

Several factors can cause chronic atrophic gastritis:

• Autoimmune reactions: The body’s immune system mistakenly attacks the stomach lining, leading to the loss of acid-producing cells.
• Chronic bacterial infection: Long-term infection with bacteria such as Helicobacter pylori (H. pylori) can cause inflammation and eventually lead to the thinning of the stomach lining.
• Prolonged use of certain medications: Regular use of medications that reduce stomach acid, like proton pump inhibitors, or anti-inflammatory drugs, such as aspirin, can contribute to the development of atrophic gastritis.
• Environmental factors: Excessive alcohol consumption, smoking, and chronic stress are also potential contributors.

How is this diagnosis made?

The diagnosis of chronic atrophic gastritis is typically made through a combination of clinical evaluation, laboratory tests, and diagnostic procedures:

• Medical history and physical examination: The doctor will ask about symptoms, dietary habits, medication use, and any family history of gastrointestinal diseases. A physical exam can help identify abdominal tenderness or other signs suggesting stomach issues.
• Blood tests: These can check for anemia, which is common due to malabsorption of vitamin B12 in chronic atrophic gastritis. Blood tests can also detect antibodies that might indicate an autoimmune cause or infection markers for Helicobacter pylori.
• Stool test: This is a noninvasive test for Helicobacter pylori infection or to check for the presence of blood in the stool, which can occur with gastritis.
• Upper gastrointestinal endoscopy: This is the most definitive test for diagnosing chronic atrophic gastritis. During an endoscopy, a flexible tube with a camera (endoscope) is passed down the throat into the stomach. This allows the doctor to visually inspect the stomach lining and take small tissue samples (biopsies).
• Biopsy and histological examination: The tissue samples taken during endoscopy are examined under a microscope to look for the specific microscopic features of chronic atrophic gastritis, such as atrophy, inflammation, ECL cell hyperplasia, and foveolar metaplasia (see below for more information).

What are the microscopic features of atrophic gastritis?

Under the microscope, atrophic gastritis displays several distinct features:

• Atrophy: Thinning of the stomach lining, with a significant reduction in the number and size of the glands.
• Inflammation: The presence of inflammatory cells in the stomach lining can further damage the tissue.
• ECL (enterochromaffin-cell like) hyperplasia: ECL cell hyperplasia is a noncancerous increase in the number of ECL cells, which are typically involved in regulating acid production by releasing hormones.
• Pseudopyloric metaplasia: Transformation of the normal glandular cells into those resembling the pyloric glands found in the deeper parts of the stomach. This type of metaplasia often occurs as a response to chronic injury.
• Intestinal metaplasia: Replacement of the normal gastric cells with intestinal-type cells featuring characteristics typical of the intestine, such as the presence of goblet cells. Intestinal metaplasia is significant because it can increase the risk of developing stomach cancer.

Dysplasia

Dysplasia is a term used to describe abnormal changes in the cells lining the stomach. These changes can occur in the setting of chronic atrophic gastritis. Dysplasia is considered a precancerous condition, meaning that it can sometimes develop into stomach cancer if left untreated.

Chronic atrophic gastritis creates an environment that increases the risk of dysplasia. In particular, chronic inflammation can damage the DNA in the cells lining the inside surface of the stomach and cause them to grow abnormally. Dysplasia often develops in areas of the stomach where the normal lining has been replaced by intestinal-type cells, a condition called intestinal metaplasia.

Dysplasia is important because it can indicate an increased risk of developing stomach cancer. Detecting dysplasia early allows doctors to monitor the condition closely and, in some cases, treat it before it progresses to cancer. Pathologists classify dysplasia into two grades based on how abnormal the cells appear under the microscope.

Chronic atrophic gastritis with low grade dysplasia

In low grade dysplasia, the cells look mildly abnormal, but they still resemble normal stomach cells to some extent. The risk of progression to cancer is lower in atrophic gastritis with grade dysplasia, but careful monitoring with regular follow-up is important to ensure the changes do not worsen over time.

Chronic atrophic gastritis with high grade dysplasia

In high grade dysplasia, the cells look much more abnormal, with significant changes in their size, shape, and organization. Atrophic gastritis with high grade dysplasia is more likely to progress to cancer if left untreated. Doctors often recommend removing or treating areas of high grade dysplasia to prevent cancer from developing.