Chronic pancreatitis

• Chronic inflammation of the pancreas with fibrosis. It has a relapsing and remitting course and is associated with irreversible impairment of pancreatic function

Causes

• Similar to acute pancreatitis,
  • Long term alcohol abuse – most common
  • Long term obstruction of the pancreatic duct – gallstones or anatomical abnormalities in the pancreatic duct
  • Tropical pancreatitis – poorly understood, occurs in Africa and Asia
  • Familial pancreatitis – autosomal dominant disorders, the same ones that are associated with acute pancreatitis
  • CF – protein plugging of ducts due to decreased bicarbonate secretion
  • 40% are idiopathic

Pathogenesis

• Not well understood. Possibilities are;
  • Protein plugging resulting in ductal obstruction – CF and alcohol. Protein plugs may calcify forming calculi
  • Direct acinar cell damage by toxins and oxidative stress
  • Interstitial fibrosis initiated by acute pancreatitis

Morphology

• Overall the pancreas is hard with focal calcification
• Chronic inflammation
• Fibrous scarring with loss of the acinar tissues but relative sparing of the islets of Langerhans until late on in disease
• Duct strictures with formation of intrapancreatic calculi
• Other ducts may be dilated and contain protein plugs

Clinical features;

• Recurrent bouts of severe abdominal pain – attacks may be precipitated by excessive alcohol, eating or drugs
• Episodes of acute pancreatitis may complicate chronic pancreatitis
• Later complications are due to loss of exocrine and endocrine function;
  • Malabsorption – diarrhoea, due to decreased lipase and proteinase secretion
  • Steatorrhoea
  • Diabetes mellitus
• Long term prognosis is poor with only 50% of patients surviving 20-25 years

Investigations

• Imaging – x-ray, ultrasound, CT, ERCP
• Functional tests;
• Secretin/CCK/stimulation test
• Glucose tolerance test
• Five day stool collection looking for fat excretion
• LFT’s