GALL STONES : Introduction

EPIDEMIOLOGY

• Prevalence 10%

• F>M (2:1)

• Incidence increases with age

“ Female, fat, fertile, fifty, fare”- kind of true.

1. Cholesterol supersaturation.

• Cholesterol normally dissolved in lecithin-bile acid.

• If the concentration of cholesterol increases, no more can dissolve ie supersaturated.

• Supersaturation occur in:

* High oestrogen states= Obesity, pregnancy, Pill.

*Decreased bile acid pool = terminal ileum disease/resection.

Therefore, enterohepatic circulation disrupted.

2. Stasis.

• Fasting: no food stimulus for GB emptying.

• TPN: As above

• Truncal vagotomy: No neural stimulus to GB

3. Increased Bilirubin secretion in bile or deconjugation.

• Bilirubin is kept soluble in bile by conjugation with glucuronide.

• Pigment stones occur when:

1. Increased breakdown of RBC: Haemolytic anaemias, Spherocytosis, SCD.

2. Failure of conjugation: Hepatocyte insufficiency to form glucuronide or XS glucuronidase. Increased bacteria as cause or effect?

Category: Surgery Notes