Pancreatic endocrine function in cystic fibrosis.

Area of Science:

• Endocrinology
• Gastroenterology
• Genetics

Background:

• Cystic Fibrosis (CF) is a genetic disorder affecting multiple organs.
• Pancreatic dysfunction, including exocrine insufficiency, is common in CF.
• The impact of CF on pancreatic endocrine cell function requires further characterization.

Purpose of the Study:

• To characterize pancreatic endocrine secretion in CF patients.
• To examine interrelationships between alpha, beta, and pancreatic polypeptide cell function alterations in CF.
• To compare endocrine function in CF patients with and without exocrine insufficiency.

Main Methods:

• Studied 19 CF patients with exocrine insufficiency (EXO) and 10 without (NEXO), plus 10 controls.
• Assessed first-phase C-peptide response to glucose and arginine.
• Measured alpha cell function via glucagon response to hypoglycemia.
• Evaluated pancreatic polypeptide response to hypoglycemia.

Main Results:

• CF patients with exocrine insufficiency exhibited significantly impaired first-phase C-peptide response to glucose.
• Alpha cell function (glucagon response) was diminished in EXO patients but not NEXO patients.
• Peak pancreatic polypeptide response to hypoglycemia clearly distinguished CF patients with exocrine insufficiency from those without.

Conclusions:

• CF patients with exocrine disease demonstrate reduced alpha, beta, and pancreatic polypeptide cell function compared to those without.
• These findings suggest exocrine disease may directly cause endocrine dysfunction in CF.
• Alternatively, a shared pathogenic process could independently impair both exocrine and endocrine functions in CF.