⚠️ Diseases & Disorders Associated with Bile Acid Imbalance
🔹 1. Cholestatic Liver Diseases
Conditions where bile flow is impaired, leading to accumulation of bile acids in the liver and blood.
🦠 Examples:
- Primary Biliary Cholangitis (PBC)
- Primary Sclerosing Cholangitis (PSC)
- Biliary Atresia (in infants)
- Drug-induced cholestasis
🔄 Consequences:
- Hepatocellular injury (bile acids are cytotoxic in excess)
- Fat malabsorption
- Pruritus (itching due to bile acid buildup)
🔹 2. Gallstone Disease (Cholelithiasis)
Caused by supersaturation of bile with cholesterol due to:
- Imbalanced bile acid–cholesterol ratio
- Decreased bile salt secretion
⚠️ Risk factors:
- Female, Fat, Forty, Fertile, Family history
- High estrogen levels
- Obesity
🔹 3. Bile Acid Diarrhea (BAD)
Occurs when excess bile acids reach the colon, stimulating secretion and motility.
🌀 Types:
- Primary BAD – idiopathic
- Secondary BAD – after ileal resection, Crohn’s disease, radiation enteritis
💡 Symptoms:
- Chronic watery diarrhea, urgency
🔹 4. Fat-Soluble Vitamin Deficiency
Bile acids are essential for absorption of vitamins A, D, E, and K.
🧬 Causes:
- Cholestasis
- Liver dysfunction
- Bile duct obstruction
🧯 Symptoms:
- Night blindness (vit A), bleeding (vit K), bone weakness (vit D), neuropathy (vit E)
🔹 5. Neonatal Cholestasis & Inherited Disorders
🧬 Genetic Diseases:
- Progressive Familial Intrahepatic Cholestasis (PFIC)
- Bile acid synthesis disorders (e.g., CYP7A1, CYP27A1 mutations)
🔹 6. Metabolic Disorders
- Altered bile acid signaling through FXR and TGR5 receptors is linked to:
- Type 2 Diabetes
- Non-Alcoholic Fatty Liver Disease (NAFLD)
- Obesity
- Dyslipidemia
✅ Summary Table
| Category | Disease Examples | Effect of Bile Acid |
| Cholestasis | PBC, PSC, Biliary atresia | Accumulation → liver damage, itching |
| Gallstones | Cholelithiasis | Reduced solubility of cholesterol |
| Malabsorption | Fat-soluble vitamin deficiencies | Inadequate emulsification of fats |
| Colon irritation | Bile acid diarrhea | Excess bile acids in colon |
| Genetic disorders | PFIC, bile acid synthesis defects | Impaired bile acid formation or transport |
| Metabolic diseases | NAFLD, diabetes, obesity | Altered bile acid signaling |