Acute Pancreatitis

Definition | Aetiology | Pathophysiology | Risk Factors | Signs and Symptoms | Investigations | Management | Referral

Definition

Acute pancreatitis is a sudden inflammatory condition of the pancreas, characterised by autodigestion of pancreatic tissue due to premature activation of digestive enzymes, leading to local and systemic complications.

Aetiology

The most common causes include:

  • Gallstones (40-70% of cases): obstruction of the pancreatic duct leads to enzyme activation.
  • Alcohol consumption (25-35% of cases): causes direct toxicity to pancreatic acinar cells.
  • Hypertriglyceridaemia: levels >10 mmol/L can trigger pancreatitis.
  • Medications: such as azathioprine, diuretics, and corticosteroids.
  • Pancreatic trauma: post-surgical or post-ERCP (endoscopic retrograde cholangiopancreatography).
  • Autoimmune pancreatitis: associated with IgG4-related disease.
  • Idiopathic causes: in 10-15% of cases.

Pathophysiology

  • Premature activation of trypsinogen within pancreatic acinar cells leads to autodigestion.
  • Inflammatory cytokines and enzymes cause pancreatic tissue damage, necrosis, and vascular leakage.
  • Severe cases lead to multi-organ dysfunction due to systemic inflammatory response syndrome (SIRS).

Risk factors

  • Gallstone disease.
  • Excessive alcohol consumption.
  • Obesity and metabolic syndrome.
  • High triglycerides (>10 mmol/L).
  • Recent ERCP procedure.
  • Autoimmune conditions (IgG4-related disease).

Signs and symptoms

Symptoms:

  • Severe, epigastric abdominal pain (radiating to the back).
  • Nausea and vomiting.
  • Anorexia.
  • Fever and malaise.

Signs:

  • Epigastric tenderness with guarding.
  • Hypotension and tachycardia (if severe).
  • Reduced or absent bowel sounds (paralytic ileus).
  • Grey-Turner’s sign: flank bruising (suggests retroperitoneal haemorrhage).
  • Cullen’s sign: periumbilical bruising (indicates severe pancreatitis).

Investigations

  • Blood tests:
    • Serum amylase or lipase (>3 times upper limit confirms diagnosis).
    • CRP >150 mg/L at 48 hours indicates severe pancreatitis.
    • Liver function tests (raised ALP, ALT >150 IU/L suggests gallstone cause).
    • Serum calcium (may be low due to fat necrosis).
    • Triglycerides (if suspected hypertriglyceridaemia-induced pancreatitis).
  • Imaging:
    • Abdominal ultrasound(first line): identifies gallstones or biliary dilatation.
    • CT abdomen (gold standard): used in severe cases to assess necrosis and complications.
    • MRCP: if bile duct obstruction is suspected.
  • Glasgow-Imrie score: used to assess severity.

Management

1. Initial Resuscitation:

  • ABCDE approach: monitor airway, breathing, circulation.
  • IV fluids: aggressive fluid resuscitation with crystalloid solutions.
  • Pain relief: IV paracetamol and opioids if needed.
  • Nil by mouth initially.

2. Specific Management Based on Cause:

  • Gallstone pancreatitis: early cholecystectomy once stable.
  • Alcohol-induced pancreatitis: alcohol cessation support and thiamine supplementation.
  • Hypertriglyceridaemia: insulin therapy and lipid-lowering agents.

3. Management of Complications:

  • Pancreatic necrosis: CT-guided drainage or surgical debridement if infected.
  • Pseudocyst formation: may require endoscopic drainage.
  • Multi-organ failure: intensive care admission if needed.

Referral

  • Urgent gastroenterology referral: if severe pancreatitis or complications arise.
  • Surgical referral: for gallstone pancreatitis requiring cholecystectomy.
  • ICU referral: if multi-organ failure develops.
GastroenterologymypanotesAcute Pancreatitis