Chronic active gastritis
This article was last reviewed and updated on April 26, 2018.
by Shaheed Hakim, MD FRCPC
Chronic active gastritis is a medical condition where an increased number of cells from the immune system are found in the tissue that lines the inside of the stomach.
These immune cells can damage the tissue and prevent the stomach from working normally.
The most common cause for chronic active gastritis is infection of the stomach by a bacteria called Helicobacter.
The stomach is a hollow organ located in the middle of your abdomen. The stomach is responsible for breaking down and absorbing food so that it can be used by your body.
The inner surface of the stomach is lined by specialized cells called foveolar cells which form a barrier called an epithelium. This barrier protects the stomach from the acid that aids in the digestion of our food.
Anything that causes irritation of the epithelium can lead to short term or long term inflammation of the stomach, a process that pathologists call gastritis. Pathologists call the process of short term inflammation acute or active and the process of long term inflammation chronic.
One very common cause of chronic inflammation of the stomach (chronic gastritis) is a bacteria called Helicobacter. Prolonged infection by Helicobacter damages the epithelium which can lead to ulcers and if left untreated even cancer.
A biopsy is usually performed because the patient has symptoms concerning for Helicobacter gastritis, such as nausea and vomiting. A diagnosis of chronic active gastritis means that your pathologist saw two types of inflammatory cells, plasma cells (evidence of chronic gastritis) and neutrophils (evidence of active gastritis) in addition to the Helicobacter along the surface of the epithelium.
Chronic active gastritis that is not treated can damage the foveolar epithelium. If the damage continues for many years, a new type of epithelium similar to the epithelium normally found in the small intestine slowly replaces the foveolar epithelium.
The change from foveolar epithelium to small intestinal epithelium is an example of metaplasia. This specific type of metaplasia that takes place in the stomach is referred to as intestinal metaplasia.
Dysplasia refers to an abnormal pattern of growth that is initially non-cancerous (benign) but can turn into cancer. Chronic inflammation (chronic gastritis) which leads to intestinal metaplasia, can then lead to dysplasia.
The earliest change is referred to as ‘low-grade’ dysplasia. The cells in low grade dysplasia are abnormal but are still non-cancerous (benign). In some cases, the cells become even more abnormal and progress to ‘high-grade’ dysplasia. These cells look very similar to cancer cells, however, they are still only seen in the epithelium on the inner surface of the stomach.
High grade dysplasia is considered a precursor because some cases will turn into cancer (a malignant tumour) over time. Your pathologist will closely examine the tissue for any evidence of dysplasia and will describe it in your report if it is seen.