Gastritis is inflammation of the gastric mucosa caused by any of several conditions, including Helicobacter pylori infection, drugs (nonsteroidal anti-inflammatory drugs [NSAIDs], alcohol), stress, autoimmune phenomena (atrophic gastritis), and a number of less common disorders.
(See also Overview of Acid Secretion and Overview of Gastritis.)
Ménétrier Disease
This rare idiopathic disorder affects adults aged 30 to 60 and is more common among men. It manifests as a significant thickening of the gastric folds of the gastric body but not the antrum. Gland atrophy and marked foveolar pit hyperplasia occur, often accompanied by mucous gland metaplasia and increased mucosal thickness with little inflammation. Hypoalbuminemia (the most consistent laboratory abnormality) caused by gastrointestinal protein loss may be present (protein-losing gastropathy). As the disease progresses, the secretion of acid and pepsin decreases, causing hypochlorhydria.
Symptoms of Ménétrier disease are nonspecific and commonly include epigastric pain, nausea, weight loss, edema, and diarrhea.
Diagnosis of Ménétrier disease is made by endoscopy with deep mucosal biopsy or full-thickness laparoscopic gastric biopsy.
Differential diagnosis includes the following:
Lymphoma, in which multiple gastric ulcers may occur
Mucosa-associated lymphoid tissue (MALT) lymphoma, with extensive infiltration of monoclonal B lymphocytes
Gastrinoma (Zollinger-Ellison syndrome) with associated gastric fold hypertrophy
Cronkhite-Canada syndrome, a mucosal polypoid protein-losing syndrome associated with diarrhea
Various treatments have been used, including anticholinergics, antisecretory medications, and corticosteroids, but none have proved fully effective. Partial or complete gastric resection may be necessary in cases of severe hypoalbuminemia.
Eosinophilic Gastritis
Extensive infiltration of the mucosa, submucosa, and muscle layers with eosinophils often occurs in the antrum. It is usually idiopathic but may result from nematode infestation.
Symptoms of eosinophilic gastritis include nausea, vomiting, and early satiety.
Diagnosis of eosinophilic gastritis is by endoscopic biopsy of involved areas.
Corticosteroids can be successful in idiopathic cases; however, if pyloric obstruction develops, surgery may be required.
Mucosa-Associated Lymphoid Tissue (MALT) Lymphoma
This rare condition is characterized by massive lymphoid infiltration of the gastric mucosa, which can grossly resemble Ménétrier disease but is distinguished on histologic examination.
Treatment of Helicobacter pylori infection may be curative in MALT lymphoma localized to the stomach.
Gastritis Caused by Systemic Disorders
Sarcoidosis, tuberculosis, amyloidosis, and other granulomatous diseases can cause gastritis, which is seldom of primary importance.
Gastritis Caused by Physical Agents
Radiation and ingestion of corrosives (especially acidic compounds) can cause gastritis. Exposure to > 6 gray of whole-body radiation (see Acute radiation syndromes) causes marked deep gastritis, usually involving the antrum more than the corpus. Pyloric stenosis and perforation are possible complications of radiation-induced gastritis.
Infectious (Septic) Gastritis
Except for H. pylori infection, bacterial invasion of the stomach is rare and mainly occurs after ischemia, ingestion of corrosives, or exposure to radiation. On x-ray, gas outlines the mucosa. The condition can manifest as an acute surgical abdomen and has a very high mortality rate. Surgery is often necessary.
Debilitated or immunocompromised patients may develop viral or fungal gastritis with cytomegalovirus, candidiasis, histoplasmosis, or mucormycosis; these diagnoses should be considered in patients with exudative gastritis, esophagitis, or duodenitis.
