Brief answer.....explained below
Detailed answer....
Hello,
Thanks for the query.
High levels of bilirubin in blood can be caused by various reasons which need to be investigated for proper treatment.
Causes include....
Physiological jaundice as it happens in newborns
Inherited problems like Gilbert's syndrome
Infections like cholecystitis ( infection of gall bladder) 
Presence of stones in gall bladder or common bile duct
Other diseases like cirrhosis,various types of hepatitis,etc
I think it serves the purpose for you,however you are most welcome to revert to me for any further query.
Best of luck
Thanks

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