Cystic fibrosis-related diabetes occurs due to what mechanism?

• A. Mucus obstruction of pancreatic beta cells
• B. Autoimmune destruction of beta cells
• C. Insulin resistance due to obesity
• D. Nutrient deficiency causing Beta cell failure

Answer: (A)

Cystic fibrosis–related diabetes mainly results from loss of insulin-producing beta cells caused by CF-related pancreatic damage. In CF, thick, sticky secretions block the pancreatic ducts, leading to chronic inflammation and progressive fibrosis of the pancreas. This fibrotic process damages the islets of Langerhans, reducing beta-cell mass and insulin secretion. Because the core issue is insulin deficiency from beta-cell loss rather than an autoimmune attack or obesity-driven insulin resistance, blood glucose rises as insulin becomes scarce. While illness or malnutrition can worsen glucose control, they don’t define the primary mechanism. The described mechanism—mucus obstruction leading to pancreatic tissue destruction and beta-cell loss—best captures why CFRD develops.