How to manage diarrhea in a patient with chronic pancreatitis?

Management of Diarrhea in Chronic Pancreatitis

Pancreatic enzyme replacement therapy (PERT) is the first-line treatment for diarrhea in patients with chronic pancreatitis, addressing the underlying pancreatic exocrine insufficiency causing malabsorption and steatorrhea. 1

Understanding the Cause

Diarrhea in chronic pancreatitis primarily results from pancreatic exocrine insufficiency (PEI), which leads to maldigestion and malabsorption, particularly of fats. This occurs because:

• Progressive destruction of pancreatic acinar tissue reduces enzyme secretion necessary for digestion
• Approximately 90% of pancreatic acinar tissue must be destroyed before symptoms of malabsorption become evident 2
• Small intestinal bacterial overgrowth (SIBO) commonly complicates PEI, occurring in up to 34% of patients 3

Diagnostic Approach

1. Confirm pancreatic exocrine insufficiency:

   • Fecal elastase testing is the preferred non-invasive test (normal values: 200-500 μg/g) 2
   • Values <100 μg/g indicate severe insufficiency 2
   • Serum enzyme quantification is not valuable for diagnosis 2

2. Rule out other causes of diarrhea:

   • Colonoscopy with biopsies to exclude microscopic colitis 2
   • Consider testing for bile acid diarrhea with SeHCAT or serum 7α-hydroxy-4-cholesten-3-one 2
   • Evaluate for SIBO, especially in patients with prior gastroduodenal surgery 3

Treatment Algorithm

1. Pancreatic Enzyme Replacement Therapy (PERT)

• Formulation: Use pH-sensitive, enteric-coated microspheres (1.0-1.2mm diameter) 1

• Initial dosing:

  • 500-1,000 lipase units/kg/meal for adults with chronic pancreatitis 4
  • Take PERT during meals and snacks 4
  • For snacks, administer approximately half the prescribed dose for a meal 4

• Titration:

  • If symptoms persist, increase dose gradually
  • Maximum dose: 2,500 lipase units/kg/meal, 10,000 lipase units/kg/day, or 4,000 lipase units/g fat ingested/day 4
  • Higher doses may be administered if documented effective by improvement in symptoms 4

2. Acid Suppression Therapy

• Add proton pump inhibitors or H2 blockers to prevent enzyme denaturation in acidic environment 1
• This improves the efficacy of PERT by maintaining optimal pH for enzyme activity

3. Treat Small Intestinal Bacterial Overgrowth

• Consider empirical antibiotic therapy if SIBO is suspected 2
• Rifaximin 400 mg three times daily for seven consecutive days each month has been shown to normalize hydrogen breath tests and reduce symptoms in patients with chronic pancreatitis and SIBO 3

4. Dietary Recommendations

• Maintain normal fat diet (30% of total energy intake) with PERT rather than restricting fat 1
• Consume frequent small meals to improve digestion 1
• Ensure protein intake of 1.0-1.5 g/kg body weight 1
• Consider medium-chain triglycerides (MCT) if steatorrhea persists despite optimal PERT 1

Monitoring and Follow-up

• Assess clinical response to PERT by:
  • Reduction in steatorrhea
  • Weight gain
  • Improvement in symptoms 1
• Titrate PERT dose based on clinical response

Common Pitfalls to Avoid

• Undertreatment: Up to 70% of chronic pancreatitis patients with PEI are undertreated 1
• Improper timing: PERT must be taken with meals and snacks to be effective 4
• Inadequate dosing: Failure to titrate dose based on clinical response 1
• Failure to recognize SIBO: Consider this complication when symptoms persist despite adequate PERT 3
• Inappropriate use of empirical PERT: Diagnosis of PEI should be confirmed before starting therapy 2

For Refractory Cases

For patients with severe malabsorption not responding to oral PERT, consider:

• Enteral nutrition via nasojejunal route
• Long-term jejunostomy access for those requiring enteral nutrition for more than 30 days 1