Bile Pigments Metabolism and Jaundice

Only about three and a half months after its birth, the red cell is doomed and is phagocytized by the cells of the reticuloendothelial system. The mechanism of the complete degradation of all the components of the red cell is not known, but the fate of the heme of hemoglobin has been investigated extensively. Between 90-100% of the heme moiety of hemoglobin is converted to bile pigment [41-43]. 

The degradation of 1 g of hemoglobin yields 30 mg of bilirubin. A normal individual destroys 7.5 g of hemoglobin per day when 1 % of his circulating erythrocytes are replaced. At that rate of erythrocyte turnover, the daily bilirubin production equals 250 mg. The maximum capacity of the reticuloendothelial system to convert hemoglobin to bilirubin is five times that amount. 

All the bilirubin found in serum does not derive from hemoglobin breakdown—10-30% has a different origin, but the exact source is not clear. It has been 

Plummer-Vinson syndrome Gastric achlorhydria Fragility of hair and nails 

After it is produced in the reticuloendothelial system, bilirubin has to be transported in the plasma. The 

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