Chronic Pancreatitis

Detailed Overview

Unlike acute pancreatitis, chronic pancreatitis results in permanent structural damage. The destruction of acinar cells leads to exocrine insufficiency (malabsorption, steatorrhea), while the destruction of Islets of Langerhans causes endocrine insufficiency (pancreatogenic diabetes or Type 3c diabetes). The hallmark symptom is intractable, debilitating abdominal pain.

Epidemiology & Demographics

Prevalence is 50 per 100,000. Most commonly diagnosed in men aged 30-40. High association with heavy alcohol use.

Etiological Mechanism

Alcohol abuse is the most common cause (TIGAR-O classification: Toxic-metabolic, Idiopathic, Genetic, Autoimmune, Recurrent and Severe Acute, Obstructive).

Primary Causes

Chronic heavy alcohol consumption (60-70% of cases). Genetic mutations (PRSS1, SPINK1, CFTR).

• Heavy Alcohol Use: Consuming >4-5 drinks/day for >5 years.
• Smoking: Acts synergistically with alcohol to accelerate pancreatic fibrosis.

Repeated episodes of acute inflammation or chronic toxic exposure cause acinar cell injury. This activates pancreatic stellate cells, transforming them into myofibroblast-like cells that deposit excessive collagen and extracellular matrix. Pancreatic juice becomes rich in protein and low in bicarbonate, leading to the precipitation of protein plugs in the ducts. These plugs calcify, causing ductal obstruction, upstream ductal dilation, and increased tissue pressure, which causes severe ischemic and perineural pain.

Characteristic Clinical Presentation

• Epigastric Pain: Severe, boring mid-epigastric pain radiating to the back, worse postprandially (eating stimulates pancreatic secretion).
• Steatorrhea: Voluminous, foul-smelling, oily stools that float, occurring when >90% of exocrine function is lost.
• Weight Loss: Due to fear of eating (sitophobia) and severe malabsorption.

Physical Examination Signs

• Malnutrition
• Epigastric Tenderness

• Pancreatogenic Diabetes (Type 3c): Loss of both insulin and glucagon, leading to brittle diabetes with a high risk of severe hypoglycemia.
• Pancreatic Pseudocyst: Fluid collection of pancreatic enzymes leading to infection, bleeding, or bowel obstruction.

Diagnostic Criteria & Guidelines

Diagnosed via imaging showing characteristic pancreatic calcifications, ductal dilation, and parenchymal atrophy, combined with clinical signs of pancreatic insufficiency.

Differential Diagnosis

• Pancreatic Adenocarcinoma (must rule out, especially if weight loss and new-onset diabetes occur together)
• Peptic Ulcer Disease
• Mesenteric Ischemia

Laboratory Tests & Biomarkers

• Fecal Elastase-1: Significantly decreased (<200 mcg/g stool) confirms severe exocrine insufficiency. Highly sensitive and specific.
• HbA1c: Elevated (>6.5%) indicating new-onset diabetes.
• Serum Amylase/Lipase: Often NORMAL in chronic pancreatitis because the gland is burned out and unable to produce enzymes.

Imaging Modalities & Findings

• MRCP (Magnetic Resonance Cholangiopancreatography):
• CT Abdomen:

• Early
  Recurrent pain attacks with preserved exocrine/endocrine function.
• Burnout (Late)
  Pain may paradoxically decrease as the gland is completely destroyed, but severe steatorrhea and brittle diabetes predominate.

Second-Line & Adjunctive Therapy

Endoscopic stenting of ductal strictures or lithotripsy for ductal stones. Opiates (e.g., Tramadol 50 mg QDS) if pain is refractory, though risk of addiction is high.

Surgical & Procedural Management

Lateral pancreaticojejunostomy (Puestow procedure) to decompress a dilated main pancreatic duct (>5 mm). Total pancreatectomy with islet auto-transplantation (TPIAT) for severe intractable pain.

Recommended Lifestyle Changes

• Absolute cessation of alcohol and smoking.
• Consume small, frequent, low-fat meals to minimize pancreatic stimulation.

Patient Counseling & Advice

Counsel on strict adherence to PERT (must take enzymes WITH the first bite of food, not after). Warn about the symptoms of hypoglycemia due to loss of glucagon.

Follow-Up & Monitoring Schedule

Annual fasting glucose/HbA1c to screen for diabetes. DEXA scan every 2 years due to Vitamin D malabsorption risk.

Preventive Strategies

Limit alcohol intake and stop smoking.

Significantly reduced quality of life due to chronic pain. High risk of mortality from cardiovascular events, infections, and malnutrition. 4% lifetime risk of developing pancreatic cancer.