About this Video

• Video Title: Gallstones (cholelithiasis)
• Channel: Osmosis from Elsevier
• Speakers: Narrator
• Duration: 00:08:13

Introduction

This video explains the formation of gallstones (cholelithiasis). It details the composition of bile, the role of the gallbladder, and how imbalances in bile components (cholesterol, bilirubin, etc.) lead to the precipitation of solids that form gallstones. Different types of gallstones (cholesterol, pigmented) and their associated risk factors are also discussed.

Key Takeaways

• Gallbladder Function: The gallbladder stores and concentrates bile, releasing it into the small intestine to aid in fat digestion.
• Bile Composition: Bile is primarily composed of bile salts/acids, cholesterol, phospholipids, and bilirubin. These components interact to keep cholesterol soluble.
• Cholesterol Gallstones: These are the most common type, forming when bile becomes supersaturated with cholesterol or when there's insufficient bile salts/acids and phospholipids to keep cholesterol soluble. Gallbladder stasis can also contribute. They are usually radiolucent (invisible on X-ray) unless they contain enough calcium carbonate.
• Pigmented Gallstones: These are formed from bilirubin, often due to excess unconjugated bilirubin. They are usually radiopaque (visible on X-ray) due to calcium content. Brown pigmented stones often indicate infection.
• Risk Factors: Risk factors for gallstones include female gender, estrogen use, obesity, and rapid weight loss.