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Cystic fibrosis: Overview of gastrointestinal disease

Sabina Sabharwal, MD, MPH
Sarah Jane Schwarzenberg, MD
Section Editors
George B Mallory, MD
Melvin B Heyman, MD, MPH
Deputy Editor
Alison G Hoppin, MD


Cystic fibrosis (CF) generally is thought of as a lung disease since much of the associated morbidity and mortality is related to pulmonary complications. A discussion of the pulmonary manifestations of CF is presented separately. (See "Cystic fibrosis: Clinical manifestations of pulmonary disease" and "Cystic fibrosis: Overview of the treatment of lung disease".)

The underlying pathophysiology of CF is related to abnormal chloride and bicarbonate transport caused by mutations in the CF transmembrane conductance regulator gene (CFTR) located on chromosome 7. The mutations cause the production of abnormally tenacious mucus and secretions in the lungs, gastrointestinal tract, pancreas, and hepatobiliary system. As a result, the lumens of these organs become obstructed leading to the clinical findings associated with this disease process. (See "Cystic fibrosis: Genetics and pathogenesis".)

Gastrointestinal complications have become an increasingly important cause of morbidity in patients with CF, in part because of improved life expectancy. Some of the complications, such as gastroesophageal reflux and constipation, are not unique to the CF population, but they are more common and warrant special considerations in diagnosis and management in the CF population. This topic review provides an overview of the gastrointestinal manifestations of CF. Pancreatic insufficiency, which is one of the most clinically important gastrointestinal issues, and other nutritional issues are addressed separately. (See "Cystic fibrosis: Assessment and management of pancreatic insufficiency" and "Cystic fibrosis: Nutritional issues".)


Gastroesophageal reflux disease (GERD) — Gastroesophageal reflux disease (GERD) appears to be more common in individuals with CF as compared with the general population [1,2]. Symptomatic GERD is reported in 30 to 40 percent of individuals with CF, and "silent" GERD detected by esophageal monitoring has been reported in up to 90 percent of individuals with severe pulmonary disease [3]. However, the magnitude of the association has not been well-defined, since GERD is common in otherwise healthy individuals and because CF is associated with other gastrointestinal disorders that may contribute to or be confused with GERD (table 1). (See "Clinical manifestations and diagnosis of gastroesophageal reflux disease in children and adolescents".)

The principal mechanism causing GERD in children with CF appears to be transient relaxation of the lower esophageal sphincter (LES), which is also the most common mechanism leading to GERD in patients without CF. Several other mechanisms may also contribute to GERD in individuals with CF:

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Literature review current through: Dec 2017. | This topic last updated: Dec 04, 2017.
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