Overview of Gallstones
Gallstones (cholelithiasis) are solid deposits that form in the gallbladder, primarily made of cholesterol or bilirubin. They are often asymptomatic, but can cause a variety of clinical symptoms, including biliary colic, cholecystitis, or cholangitis, when they obstruct the biliary ducts.
Types of Gallstones
- Cholesterol Stones: These are the most common type, formed when there is an imbalance between cholesterol and bile acids. They are associated with risk factors such as obesity, rapid weight loss, and hyperlipidemia.
- Pigment Stones: These are composed of bilirubin and calcium salts, commonly seen in hemolytic diseases like sickle cell anaemia or cirrhosis.
- Mixed Stones: Contain both cholesterol and calcium salts, often found in patients with chronic gallbladder disease.
Biliary Colic: Pathophysiology
- Biliary colic occurs when a gallstone temporarily obstructs the cystic duct, leading to increased pressure within the gallbladder. This causes episodic right upper quadrant (RUQ) pain, typically following a fatty meal.
- The pain usually lasts 30 minutes to a few hours and resolves as the stone moves or falls back into the gallbladder.
Clinical Features of Biliary Colic
- Classic Presentation: Sudden onset of severe, steady pain in the right upper quadrant or epigastrium, often radiating to the back or right shoulder.
- Timing: The pain often occurs after meals, particularly after consuming fatty foods, and typically lasts 1-4 hours.
- Associated Symptoms: Nausea, vomiting, bloating, and dyspepsia. Fever or jaundice suggests complications like cholecystitis or cholangitis.
- No Inflammatory Signs: In contrast to acute cholecystitis, biliary colic does not present with fever or leukocytosis, and physical examination may be relatively unremarkable aside from tenderness in the RUQ.
Diagnosis of Gallstones and Biliary Colic
- Ultrasound: The gold standard for diagnosing gallstones. It can detect gallstones, sludge, and gallbladder wall thickening. In biliary colic, the ultrasound typically shows gallstones but no signs of inflammation (normal gallbladder wall thickness, no pericholecystic fluid).
- Liver Function Tests (LFTs): Usually normal in uncomplicated biliary colic. Elevated LFTs suggest common bile duct (CBD) involvement or cholestasis.
- Magnetic Resonance Cholangiopancreatography (MRCP): Used when choledocholithiasis (CBD stones) is suspected but not visualized on ultrasound.
- Endoscopic Retrograde Cholangiopancreatography (ERCP): Diagnostic and therapeutic for choledocholithiasis or biliary obstruction. ERCP allows for stone extraction but carries risks like pancreatitis.
Management of Gallstones and Biliary Colic
- Asymptomatic Gallstones: Most patients with gallstones are asymptomatic, and no treatment is required unless the patient is at risk for complications (e.g., immunosuppressed patients).
- Symptomatic Gallstones (Biliary Colic)
- Initial Management: Pain relief with NSAIDs (e.g., ibuprofen or diclofenac) or opioids in more severe cases. Antiemetics (e.g., metoclopramide) can help with nausea.
- Definitive Treatment: Elective cholecystectomy (surgical removal of the gallbladder) is recommended to prevent recurrent episodes and complications such as cholecystitis. Laparoscopic cholecystectomy is the preferred approach.
- Non-surgical Options: In patients who are poor surgical candidates, ursodeoxycholic acid may be used to dissolve cholesterol stones, though this is rarely used due to limited effectiveness and slow response.
Complicated Gallstone Disease
- Acute Cholecystitis: Involves infection and inflammation of the gallbladder, presenting with fever, elevated WBC, and positive Murphy’s sign. Managed with antibiotics and early cholecystectomy.
- Choledocholithiasis: Stones in the common bile duct may cause obstructive jaundice, cholangitis, or pancreatitis. Managed with ERCP for stone removal, followed by cholecystectomy.
- Gallstone Pancreatitis: Occurs when gallstones block the pancreatic duct, leading to inflammation of the pancreas. Managed with supportive care, ERCP, and cholecystectomy once stable.
Prevention
- Encourage weight loss in obese patients, but avoid rapid weight loss as this increases the risk of gallstone formation.
- Avoid high-fat diets, as they may trigger biliary colic in patients with gallstones.
- Ursodeoxycholic acid may be considered in high-risk patients (e.g., those undergoing rapid weight loss) to prevent cholesterol stone formation.
Complications of Untreated Gallstones
- Acute Cholecystitis: Infection of the gallbladder requiring emergency treatment.
- Choledocholithiasis and Cholangitis: Stones in the common bile duct may lead to biliary obstruction, jaundice, and ascending infection (cholangitis).
- Gallstone Pancreatitis: A life-threatening condition if gallstones obstruct the pancreatic duct, causing inflammation of the pancreas.
Conclusion
Gallstones and biliary colic are common causes of upper abdominal pain. Symptomatic patients typically require elective cholecystectomy to prevent recurrent episodes and complications. Early recognition of complications such as acute cholecystitis, cholangitis, and pancreatitis is crucial for prompt intervention.