The esophagus, stomach and intestines are lined with a mucus membrane. The mucus membrane acts as a barrier against stomach acid and pepsin. Gastritis is the condition that occurs when that lining becomes inflamed.


Gastritis can be classified according to how severe it is. It may be classified by the part of the gastrointestinal (GI) tract involved. It may be acute or chronic, based on the type of cell involved.


Acute Erosive Gastritis

Common causes include use of certain drugs (such as aspirin), alcohol and acute stress. Less common causes include radiation, viral infections, blood vessel injury and trauma.

Lesions that do not penetrate into the deeper layers of the stomach are often accompanied by some degree of bleeding.

The onset of the condition likely involves a breakdown of normal body defense systems in a severely ill patient.

Typically, the patient is too ill to complain of stomach symptoms. If symptoms are present, they are usually mild and vague. The first obvious sign may be blood seen when the patient blows his or her nose. This usually happens within 2 to 5 days of the start of the illness.

Once heavy bleeding occurs, the death rate is about 60%. Having many blood transfusions may further reduce the chance of making the bleeding stop. Identifying at-risk patients and preventing bleeding are essential. However, continued bleeding is common.


Chronic Erosive Gastritis

Ulcers are present in this condition. Causes may be drugs (especially aspirin), Crohn's disease or viral infections.

Symptoms may include nausea, vomiting, and stomach discomfort. Patients may not show any signs of the condition.

Treatment includes the use of antacids and certain other drugs. Patients are advised to avoid foods that may make the condition worse. It is common for the condition to go away and come back again.


Nonerosive Gastritis

A bacteria causes almost all cases of the disorder. Infection usually leads to inflammation. That leaves the lining open to damage by acid. In some patients, infection involves the entire stomach. This may cause development of ulcers and precancer cells.

Poor sanitary conditions, poor hygiene, and crowded living conditions may be causes of the infection.

The bacteria causing the infection may be found in the stool, saliva, and dental plaque. This may be how the condition travels from person to person.

Nonerosive gastritis is diagnosed by doing a biopsy. Other tests may also be done to check for infection.

Treatment of chronic cases involves medications to get rid of the infection. Medications that limit the production of acid may also be used.


Postgastrectomy Gastritis

For this condition, the affected area may begin to waste away after stomach tissue is removed.

Some patients may show a deficiency in vitamin B12.


Pernicious Anemia

Pernicious anemia occurs when vitamin B12 cannot be absorbed. In this condition, the wasting away of stomach glands is severe.

This disease may be inherited or it may be caused by problems with the immune system. In some patients, infection may be the cause. Stomach surgery and acid-suppressing drugs may also result in development of the condition.

Pernicious anemia increases the risk of stomach cancer.