A 5-year-old child with cystic fibrosis (CF) is being seen for a follow-up visit. The parents report that the child has difficulty gaining weight despite a high- calorie diet and frequently experiences loose, fatty stools. The healthcare provider prescribes pancreatic enzyme replacement therapy (PERT) to assist with digestion. Which of the following statements best explains why children with CF require digestive enzymes?

A. Pancreatic enzyme replacement therapy (PERT) is not tied to the development of diabetes. While CF-related diabetes can occur due to progressive pancreatic damage, enzyme therapy is required much earlier to address malabsorption caused by blocked pancreatic ducts. Waiting for diabetes to develop would allow continued nutrient deficiencies, poor weight gain, and fat-soluble vitamin deficiencies (A, D, E, K). B. Children with CF do not digest fats more efficiently than carbohydrates. In fact, fat digestion is particularly impaired because pancreatic lipase is insufficient due to duct obstruction. Proteins and carbohydrates are also affected to a lesser extent. PERT provides a mix of lipase, amylase, and protease to compensate for this deficiency and ensure adequate nutrient absorption. C. CF does not cause an overproduction of digestive enzymes. On the contrary, thick mucus blocks pancreatic ducts, preventing enzymes from reaching the intestines. This blockage leads to enzyme deficiency in the gastrointestinal tract, resulting in malabsorption, steatorrhea (fatty stools), abdominal bloating, and poor growth. D. In CF, mutations in the CFTR gene lead to thick, sticky mucus production in multiple organs, including the pancreas. This mucus obstructs the pancreatic ducts, preventing digestive enzymes such as lipase, amylase, and protease from reaching the small intestine. Without these enzymes, fats, proteins, and carbohydrates are incompletely digested, causing nutrient malabsorption, fatty stools, and poor weight gain. PERT replaces the missing enzymes, allowing proper digestion and absorption of nutrients, improving growth, and reducing gastrointestinal symptoms. Regular dosing with meals and snacks is essential to optimize nutrient absorption and support normal growth and development in children with CF.