IR spectrometry determination of chemical composition of bilestone
The composition of gallstones can vary greatly, ranging from almost pure cholesterol to pigments and calcium salts. Infrared (IR) spectroscopy provides accurate identification of the composition of the stone, which plays an important role in selecting the optimal treatment, including surgical intervention if necessary.
Main types of stones according to the results of IR analysis:
Cholesterol stones (cholesterol ≥ 70%)
- The most common type (up to 80% of cases)
- Associated with obesity, diabetes, fatty diet
Pigment stones
- Black: formed in liver cirrhosis, hemolytic conditions
- Brown: may form as a result of infections of the bile ducts (e.g., E. coli, Klebsiella)
Mixed stones
- Complex formations containing cholesterol, calcium, and bilirubin – often in patients with chronic cholecystitis
Calcium compounds (carbonates, etc.)
- Rare formations that may be a sign of metabolic disorders
Why is the composition of the stone important?
- Helps identify the cause of formation (infectious, metabolic)
- Assesses the need for surgical intervention
- Guides preventive therapy – e.g., ursodeoxycholic acid for cholesterol stones
Material for testing
- The analysis is performed on stones removed during cholecystectomy or endoscopic retrograde cholangiopancreatography (ERCP).