Diagnostic Workup Diagnostic tests		Initial laboratory tests include: Liver enzymes - ALT, AST, alkaline phophatase - GGTP not routinely indicated serum glucose, urine for reducing substances recheck/redo neonatal screen for galactosemia, hypothyroidism CBC, prothrombin time, albumin alpha-1-antitrypsin level blood, urine cultures TORCH titers, urine for CMV serum amino acids, ferritin, urine organic acids chest Xray for vertebral arch anomalies, situs inversus Ultrasound of the liver and biliary tree is definitely recommended in the workup of cholestasis. While most helpful in diagnosing choledochal cyst, it can also be useful in the diagnosis of biliary atresia. Nuclear medicine scintiscans of the liver and spleen are NOT routinely recommended by NASPGHAN. Experience in young infants is too limited to comment on ERCP or MRI of the biliary tract. Percutaneous liver biopsy remains the diagnostic procedure of choice in the workup of the infant with cholestasis. If interpreted by an experienced pathologist, it has a sensitivity and specificity more than 90% for biliary atresia. However, remember that many of these diseases evolve over time; equivocal early results may necessitate a repeat biopsy in 2-4 weeks. Also remember that when a specific disease has been found (e.g. bacterial sepsis) but the cholestasis does not resolve with treatment of the disease, further workup is indicated. Repeat liver biopsy is also warranted in any patient with an atypical course - prolonged cholestasis (> 3-4 months), recurrence of cholestasis after apparent resolution or onset of new symptoms (e.g. hypoglycemia or seizures). Return to top of page