The Pathophysiology of Malabsorption

Physiological digestion and absorption of nutrients within the gastrointestinal tract requires a complex interaction between motor, secretory, digestive, and absorptive functions that is vulnerable to a multitude of potential disturbances which may lead to global or specific malabsorption syndromes. Potential pathomechanisms that are illustrated in this article include insufficient mechanical breakdown of harder food components due to chewing problems and/or decreased antral contractility, critical reduction of time for absorption in patients with markedly enhanced upper gastrointestinal transit (e.g. dumping syndrome), impaired digestion and absorption of nutrient components caused by reduced gastric acid secretion, pancreatic exocrine insufficiency or reduced biliary secretion, defects of the enteral mucosa with enzyme deficiencies (e.g. disaccharidases) or lack of specific carrier mechanisms (e.g. hexose or aminoacid transporters), and critical quantitative loss of intestinal mucosa in patients with short bowel syndrome.