Gastrointestinal System / Nutrition

Heartburn and acid regurgitation, often worse when supine or after meals. First step is lifestyle modification plus an empiric trial of a proton pump inhibitor (PPI); endoscopy is reserved for alarm features.

Dysphagia, odynophagia, unintentional weight loss, GI bleeding (hematemesis/melena), iron-deficiency anemia, persistent vomiting, or onset of new symptoms at age >60. These warrant EGD to exclude malignancy or complicated disease.

Metaplastic replacement of the normal squamous esophageal epithelium with columnar (intestinal-type) epithelium due to chronic GERD. It is a premalignant lesion that increases the risk of esophageal adenocarcinoma and requires endoscopic surveillance.

Progressive dysphagia to both solids AND liquids, regurgitation of undigested food, and chest pain. Barium swallow shows a 'bird-beak' tapering of the distal esophagus; esophageal manometry is confirmatory, showing incomplete LES relaxation and absent peristalsis.

Degeneration of inhibitory ganglion cells (myenteric/Auerbach plexus) in the distal esophagus and LES, leading to failure of LES relaxation and loss of peristalsis.

Portal hypertension (most often from cirrhosis) causes dilation of esophageal submucosal veins. Acute bleeding is managed with IV octreotide (splanchnic vasoconstriction), antibiotics (ceftriaxone prophylaxis), and urgent endoscopic band ligation, plus resuscitation.