Chronic Pancreatitis

Excerpt

The pancreas is an accessory organ of digestion with dual roles in the endocrine and exocrine systems. This organ plays a crucial role in digesting proteins, carbohydrates, and fats, working alongside bile from the common bile duct. Structurally, the pancreas contains a main pancreatic duct that joins with the common bile duct at the ampulla of Vater, an accessory duct that normally drains into the duodenum at the minor papilla, and smaller branched ducts emerging from the main pancreatic duct. These ducts can become obstructed or genetically malformed. Chronic inflammation can lead to scarring and fibrosis, causing permanent damage that impairs secretory functions.

Chronic pancreatitis is a progressive inflammatory disease affecting both pancreatic functions. Exocrine dysfunction leads to pancreatic insufficiency, steatorrhea, and weight loss, occurring when over 90% of the organ is damaged. In severe cases, pancreatic insufficiency affects up to 85% of patients. Endocrine dysfunction results in pancreatogenic diabetes, also known as type 3c diabetes.

In 2016, international pancreas societies adopted a mechanistic definition of chronic pancreatitis. This definition characterizes end-stage chronic pancreatitis as pancreatic atrophy, fibrosis, pain syndromes, duct distortion and strictures, calcifications, pancreatic exocrine dysfunction, pancreatic endocrine dysfunction, and dysplasia, but also addresses the disease mechanism as a pathological fibroinflammatory syndrome of the pancreas in individuals with genetic, environmental, or other risk factors who develop persistent pathologic responses to parenchymal injury or stress.

Chronic pancreatitis differs from acute pancreatitis, which presents with sudden-onset abdominal pain radiating to the back. Patients with chronic pancreatitis may be asymptomatic for long periods or may experience persistent abdominal pain requiring hospitalization. Histologically, acute pancreatitis is characterized by predominant neutrophilic infiltration, whereas chronic pancreatitis primarily involves mononuclear cell infiltration.