Barrett esophagus, or Barrett metaplasia, describes the phenotypic change of normal esophageal squamous epithelium to a columnar and intestinal-type epithelium. This metaplastic change is important because patients with Barrett esophagus have an increased risk of esophageal adenocarcinoma. The main cause of Barrett metaplasia is gastroesophageal reflux (GER; 109350). The retrograde movement of acid and bile salts from the stomach into the esophagus in this disease causes prolonged injury to the esophageal epithelium and induces chronic esophagitis, which in turn is believed to trigger the pathologic changes (summary by Wong et al., 2005).

Dilatation of the bladder postnatally.

Difficulty in swallowing.

Inflammation of the esophagus.

Blockage or impairment of the normal flow of the contents of the intestine towards the anal canal.

A functional rather than mechanical obstruction of the intestines, associated with manifestations that resemble those caused by an intestinal obstruction, including distension, abdominal pain, nausea, vomiting, constipation or diarrhea, in an individual in whom a mechanical blockage has been excluded.

Protrusion of the rectal mucous membrane through the anus.

Abnormal twisting of a portion of intestine around itself or around a stalk of mesentery tissue.

Decreased strength of the muscle layer of stomach, which leads to a decreased ability to empty the contents of the stomach despite the absence of obstruction.

An abnormality of the intestinal rotation and fixation that normally occurs during the development of the gut. This can lead to volvulus, or twisting of the intestine that causes obstruction and necrosis.

Dilation and elongation of the duodenum with hypertrophy of all layers of the duodenum.

Constipation for longer than three months with fewer than 3 bowel movements per week, straining, lumpy or hard stools, and a sensation of anorectal obstruction or incomplete defecation.

Inflammation of the intestine leading to bacterial invasion causing cellular damage and death which causes necrosis of the colon and intestine.

A condition in which the stomach contents leak backwards from the stomach into the esophagus through the lower esophageal sphincter.

A pathological narrowing of the esophagus that is caused by the development of a ring of scar tissue that constricts the esophageal lumen.

Reduced or inadequate esophageal peristalsis, with resultant slow passage of contents through the esophagus.

The presence of a hernia in which the upper part of the stomach, i.e., mainly the gastric cardia protrudes through the diaphragmatic esophageal hiatus.