Case Prelude: A 7-month-old infant is brought to the clinic with chronic diarrhea, failure to gain weight, and swelling of the lower limbs. The parents report that the baby has greasy stools and appears weak despite adequate feeding. Laboratory investigations reveal hypoalbuminemia, hypoproteinemia, and normal pancreatic enzyme levels. A duodenal biopsy shows absent enteropeptidase activity.What is the primary mechanism responsible for this infant’s symptoms?
