Gallstone Pancreatitis: Causes, Symptoms, Treatment & Prevention

What is gallstone pancreatitis?

Gallstone pancreatitis is inflammation of the pancreas caused by a gallstone that has migrated into the common bile duct and impacted at the ampulla of Vater – the common opening where the bile duct and pancreatic duct empty into the duodenum. The obstruction causes pancreatic enzymes to back up, digesting the pancreas itself. This is a potentially fatal condition, with mild cases resolving in days but severe cases leading to multi‑organ failure, infected necrosis, and death. Gallstones are the most common cause of acute pancreatitis, accounting for 30‑50% of all cases.

Causes – how gallstones trigger pancreatitis

The mechanism is a “stone at the ampulla”. Small gallstones (<5mm) are most dangerous because they can pass through the cystic duct into the common bile duct and lodge at the ampulla. The stone obstructs both the bile duct and the pancreatic duct, leading to:

• Backflow of bile into the pancreatic duct (biliary reflux).
• Activation of pancreatic enzymes within the pancreas (autodigestion).
• Release of inflammatory mediators, causing pancreatic oedema, necrosis, and systemic inflammation.

Risk factors: small gallstones, multiple stones, female sex, age >60, and a dilated common bile duct.

Symptoms – severe epigastric pain radiating to back, nausea, vomiting

The classic presentation of acute pancreatitis includes:

• Severe epigastric (upper middle) pain: Constant, boring, radiating straight through to the back. Often described as “band‑like” or “through and through”.
• Nausea and vomiting – persistent, not relieved by vomiting.
• Abdominal distension and tenderness.
• Fever and tachycardia.
• Jaundice (if associated common bile duct stone).
• Shock (hypotension, confusion) in severe cases.

Diagnosis – lipase/amylase, CT, ultrasound

Diagnosis requires two of the following three criteria (Atlanta classification):

• Typical abdominal pain (epigastric radiating to back).
• Serum lipase or amylase >3 times the upper normal limit. Lipase is more specific and remains elevated longer.
• Imaging findings (CT, MRI, ultrasound) consistent with acute pancreatitis.

Imaging:

• Abdominal ultrasound: Detects gallstones and CBD dilation. Cannot directly visualise the pancreas well due to overlying bowel gas.
• Contrast‑enhanced CT (CECT): Gold standard for assessing severity, necrosis, and complications. Performed after 48‑72 hours (not immediately unless diagnostic doubt).
• MRCP (magnetic resonance cholangiopancreatography): For suspected CBD stones or when CT is equivocal.

Severity scoring (Ranson, Glasgow, CT severity index)

Assessing severity helps guide treatment and predict prognosis:

• Ranson’s criteria (at admission and 48 hours): 11 parameters. Score ≥3 predicts severe pancreatitis.
• Glasgow (Imrie) score: 8 parameters, simpler. Score ≥3 indicates severe.
• CT severity index (CTSI): Combines degree of pancreatic inflammation and necrosis. CTSI ≥7 predicts high morbidity and mortality.

Treatment – IV fluids, pain relief, ERCP, cholecystectomy

Treatment is multidisciplinary and depends on severity:

• Aggressive intravenous fluid resuscitation: Crystalloids (Ringer’s lactate) at 200‑300 mL/hour. Critical to prevent hypovolaemic shock.
• Pain management: Opioids (morphine, hydromorphone) – safe in pancreatitis (myths about sphincter spasm are unfounded).
• Nutrition: Early enteral feeding (nasogastric or nasojejunal) if oral intake not tolerated. Parenteral nutrition only if enteral fails.
• ERCP (endoscopic retrograde cholangiopancreatography):
  • Indicated for: Gallstone pancreatitis with evidence of common bile duct obstruction (jaundice, cholangitis, or dilated CBD).
  • Timing: Urgent ERCP (within 24‑48 hours) for severe pancreatitis or cholangitis. For mild pancreatitis without obstruction, ERCP can be delayed until after recovery.
  • Procedure: Sphincterotomy and stone extraction from the bile duct.
• Cholecystectomy:
  • Mild pancreatitis: Perform during the same hospital admission (within 2‑4 days) after symptoms resolve.
  • Severe pancreatitis (necrotising): Delay cholecystectomy for 4‑6 weeks after discharge, once peripancreatic inflammation subsides.
• Intensive care: For organ failure, vasopressors, or renal replacement therapy.

Complications – necrotising pancreatitis, pseudocyst, organ failure

Severe gallstone pancreatitis can lead to:

• Acute necrotising pancreatitis (10‑20%): Pancreatic parenchymal necrosis. Infected necrosis requires drainage (endoscopic or surgical necrosectomy).
• Pancreatic pseudocyst: Fluid collection that persists for >4 weeks. May cause pain, gastric obstruction, or infection.
• Acute respiratory distress syndrome (ARDS).
• Acute kidney injury.
• Multi‑organ failure (MOF).
• Recurrent pancreatitis (if cholecystectomy is not performed).

Interactive FAQ – Gallstone pancreatitis

Disclaimer: This information is for educational purposes. If you have severe epigastric pain radiating to the back, seek immediate medical attention at Vivekananda Hospital.