All of these conditions can block the biliary pathway. Gall stones form in the gall bladder where bile is stored, and they can block the release of the bile which contains bilirubin. The gall bladder is a small sac that releases bile into the intestines to aid in digestion. Fibrosis results in the formation of fibrous tissue and carcinomas can be manifested as tumors, both of which are physical obstructions to conjugated bilirubin as it is traveling to the intestine.