Menetrier disease is a rare disorder characterised by massive overgrowth of mucous cells (foveola) in the mucous membrane lining the stomach, leading to large gastric folds. It manifests itself in epigastric pain, nausea, vomiting and peripheral edema (swelling of the lower legs or hands).
image from https://pubs.rsna.org/doi/10.1148/rg.291075216
The cause of the disease is unknown and remains to be a mystery. The mystery aspect is introduced as there is significant confusion and contradiction surrounding this disorder.
The diagnosis and treatment hence is specific and can be tricky to navigate. Frequently, this disease is used to describe any disease with large gastric folds and has been used synonymously with giant hypertrophic gastritis (GHG). However, Menetrier disease is not a true form of gastritis. A diagnosis of Menetrier disease should be reserved for individuals with large gastric folds due to overgrowth of mucous cells. There is minimal or no stomach inflammation in Menetrier disease. Because inflammation is minimal or not present, Menetrier disease is classified as a form of hyperplastic gastropathy and not as a form of gastritis. Some researchers believe that Menetrier disease and GHG may be variants of the same disorder or different parts of one disease spectrum.
Symptoms
The symptoms of Menetrier disease may vary from case to case. Some individuals may not exhibit any symptoms (asymptomatic). The most common symptom is pain in the upper middle region of the stomach (epigastric pain). Less frequent reported symptoms include nausea, vomiting, and diarrhoea. In some cases, weight loss and profound loss of appetite (anorexia) may also occur.
An additional variable finding sometimes associated with Menetrier disease is the loss of protein from the circulation into the gastrointestinal tract (protein-losing gastropathy) such as the loss of the protein albumin (hypoalbuminemia). Protein loss may be severe in some cases. Protein loss may result in fluid accumulation (edema), especially in the legs.
Gastrointestinal bleeding has also been reported in some cases of Menetrier disease usually as a result of erosions or ulcers in the stomach lining. Acid secretion by the stomach is often markedly decreased (hypochlorhydria) or absent. Excess mucous secretion in the stomach may also occur.
Some researchers believe that individuals with Menetrier disease have a greater risk of developing gastric cancer than the general population has. However, other researchers do not believe this to be proven with certainty. In some series, there has been an association between Menetrier disease and ulcerative colitis.
Cause?
The exact cause of Menetrier disease is unknown. There may be multiple causes. In children, some cases of Menetrier disease may be associated with infection with cytomegalovirus (CMV). The bacterium Helicobacter pylori has been implicated in some adults with Menetrier disease. The exact role, if any, that these infections play in the development of Menetrier disease is unknown.
Some researchers believe that the large gastric folds that characterise Menetrier disease may result from increased activation of the epidermal growth factor receptor in the stomach by a protein called transforming growth factor-alpha (TGF).
In extremely rare cases, siblings of affected patients have developed Menetrier disease as children suggesting a genetic link in these cases. Researchers believe that, in these cases, Menetrier disease may be inherited as an autosomal dominant trait. Genetic diseases are determined by two sets of genes, one received from the father and one from the mother. Dominant genetic disorders occur when only a single copy of an abnormal gene is necessary for the appearance of the disease. The abnormal gene can be inherited from either parent or can be the result of a new mutation (gene change) in the affected individual. The risk of passing the abnormal gene from affected parent to offspring is 50% for each pregnancy regardless of the sex of the resulting child.
Menetrier disease affects males slightly more often than females. It most often affects adults in their 50s or older. However, a childhood form of the disorder exists. Because of the confusion in the literature regarding the term Menetrier disease, it is difficult to determine its true frequency in the general population.
Diagnosis
Menetrier disease may be suspected in individuals with large gastric folds. Large gastric folds may be diagnosed by a radiologic study after the patient drinks a barium solution or by an endoscopic exam, a procedure in which a thin, flexible tube (endoscope) is inserted through the mouth and used to examine the interior of the stomach and, if necessary, to obtain tissue samples for microscopic study (biopsy). Histopathologic study of affected stomach tissue obtained by biopsy can support a diagnosis of Menetrier disease. Histopathology is the study of microscopic anatomical changes in diseased tissue.
Treatment?
Menetrier disease has been treated with anticholinergic drugs, acid suppression therapy, and antibiotic therapy directed against H. pylori infection. These therapies have produced inconsistent results. In some cases, a high-protein diet may be recommended to combat protein loss. Albumin transfusions may also be used to replace albumin loss.
Cetuximab (Erbitux) infusions block the epidermal growth factor receptor and have been successful in some patients with Menetrier disease. Cetuximab treatment can improve quality of life, restore gastric acid production and possibly even reduce the thickness of the stomach wall. In a few cases, after cetuximab infusions are discontinued the patient remains well, at least temporarily. Erbitux may cause cardiopulmonary arrest, an acne-like rash and low levels of magnesium, and thus patients must be carefully monitored on this treatment.
Written by: Svasti Tewari
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