F2 and Hyperbilirubinemia: If the infant has conjugated hyperbilirubinemia, we must evaluate common blood cell counts and the levels of AST, ALT, alkaline phosphatase, GGT, albumin, blood ammonia, prothrombin time, and activated partial thromboplastin time, and perform tests for toxoplasma, herpes simplex virus, rubella, cytomegalovirus, and abdominal sonography.