Gastroesophageal reflux disease (GERD), gastro-oesophageal reflux disease (GORD), gastric reflux disease, or acid reflux disease is a chronic symptom of mucosal damage caused by stomach acid coming up from the stomach into the esophagus.
GERD is usually caused by changes in the barrier between the stomach and the esophagus, including abnormal relaxation of the lower esophageal sphincter, which normally holds the top of the stomach closed; impaired expulsion of gastric reflux from the esophagus, or a hiatal hernia. These changes may be permanent or temporary (“transient”).
GERD has been found to be prevalent in children with cystic fibrosis (CF) and may further worsen lung damage via reflex bronchospasm or pulmonary aspiration. Chest physiotherapy may result in increased episodes of GERD as demonstrated in children. Lung transplantation may worsen pre-existing GERD.