Pancreatitis, Chronic

Source: Bolesta S, Montgomery PA. Pancreatitis. In: DiPiro JT, Talbert RL, Yee GC, Matzke GR, Wells BG, Posey LM, eds. Pharmacotherapy: A Pathophysiologic Approach. 8th ed. http://accesspharmacy.com/content.aspx?aid=7979530. Accessed July 22, 2012.

• Progressive disease characterized by long-standing pancreatic inflammation that eventually leads to loss of pancreatic exocrine and endocrine function.

• 70–80% of cases due to chronic alcohol consumption.
• 20% of cases idiopathic.
• 10% of cases due to rare causes, for example:
  • Autoimmune
  • Hereditary
  • Tropical pancreatitis

• Long-standing pancreatic inflammation leads to destruction of pancreatic tissue with fibrin deposition with loss of exocrine and endocrine function.
• Abdominal pain may be caused by increased pancreatic parenchymal pressure from obstruction, inflammation, and necrosis.
• Malabsorption of protein and fat occurs when capacity for enzyme secretion reduced by 90%.
• Complications may include pancreatic pseudocyst, abscess, and ascites or common bile duct obstruction leading to cholangitis or secondary biliary cirrhosis.

• Occurs in 6 per 100,000 population, with peak incidence between ages 35 and 54.
• About 85% of cases occur in men.
• Prevalence varies widely basedon geographic location.

• Avoidance of known risk factors.

• Increased or excessive alcohol consumption
• Cigarette smoking
• High fat and protein diet
• Hypertriglyceridemia
• Hereditary or familial pancreatitis
• Possible gene mutations
• Pancreatic duct obstruction
• Chronic kidney disease
• Medications
• Toxins

Signs and Symptoms

• Deep, penetrating epigastric or abdominal pain that may radiate to the back.
• Pain often occurs with meals and at night, and may be associated with nausea and vomiting.
• Steatorrhea, azotorrhea, diarrhea, bloating, and weight loss may occur.
• Pancreatic diabetes a late manifestation associated with pancreatic calcification.
• Jaundice occurs in ~10% of patients.

Means of Confirmation and Diagnosis

• Clinical presentation and imaging or pancreatic function studies.

Laboratory Tests

• Serum amylase and lipase usually normal or only slightly elevated but may be increased in acute exacerbations.
• Total bilirubin, alkaline phosphatase, and hepatic transaminases may be elevated with ductal obstruction.
• Serum albumin and calcium may be low with malnutrition.
• Pancreatic function tests include:
  • Serum trypsinogen (<20 ng/mL abnormal)
  • Fecal elastase (<200 mcg/g of stool abnormal)
  • 72-hour fecal fat estimation (>7 g/day abnormal)
  • Secretin stimulation (evaluates duodenal bicarbonate secretion)
  • 13C-mixed triglyceride breath test

Imaging

• Abdominal ultrasound
• Computed tomography (CT)
• Magnetic resonance cholangiopancreatography (MRCP)

Diagnostic Procedures

• Endoscopic ultrasonography (EUS)
• Endoscopic retrograde cholangiopancreatography (ERCP)
• Histology generally not recommended.

Differential Diagnosis

• Cholelithiasis
• Diabetes mellitus
• Malabsorption from other causes
• Intractable duodenal ulcer
• Pancreatic cancer
• Irritable bowel syndrome

• Relieve abdominal pain.
• Treat complications of malabsorption and glucose intolerance.
• Improve quality of life.

• Abstinence from alcohol and smoking cessation
• Smaller, more frequent meals and reduced dietary fat intake to reduce steatorrhea
• Consider whole protein or peptide-based oral nutritional supplements for patients who do not consume adequate dietary calories.
• Consider invasive procedures and surgery for uncontrolled pain and complications.

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