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What is Pigment stone is composed of? and explain in detail?
Ans. (a) Ca bilirubinate(Ref: Robbins 9th/pg 877)Two main types of gallstones:Cholesterol stones (most common type in West) containing crystalline cholesterol monohydrate.Pigment stones composed mainly of calcium bilirubinate; contain <20% cholesterol and are classified into "black" & "brown" types, the latter forming secondary to chronic biliary infection.