This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pediatrics
[{'content': 'In neonatal cholestasis, if the serum gamaglutamyl–transpeptidase (gamma GTP) is more than 600 IU/L the most likely diagnosis is – \nSelect and explain. \nA. Neonatal hepatitis, B. Choledochal cyst, C. Sclerosing cholangitis, D. Biliary atresia', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Neonatal cholestasis\n\nNeonatal cholestasis is defined as prolonged elevation of serum levels of conjugated bilirubin beyond the first 14 days of life.\nNeonatal cholestasis can be divided into extrahepatic and intrahepatic disease and clinical features of any form of cholestasis are more or less similar.\nNeonatal hepatitis is the prototype of intrahepatic cholestasis\nBiliary atresia is the prototype of extrahepatic biliary atresia\n\nEnzymes that reflect cholestasis: There are three enzymes that are usually elevated in cholestasis\n\nAlkaline phosphatase → Found in or near bile canalicular membrane of hepatocytes\n5\' nucleotidase\nGamma glutainyl transpeptidase → Located in the endoplasmic reticulum and in bile duct epithelial cells.\n\n\nBecause GGT is more diffusely localized in the liver, its elevation in serum is less specific than are the elevation of Alkaline phosphatase & 5\' nucleotidase.\nNevertheless, the following distinction is worthwhile.\n\n"GGT levels are commonly elevated to values more than 10 times normal in biliary atresia while in hepatic causes it is raised to about three times normal."\nNormal values for GGT is about 5-40 IU/L and thus a value of 600 IU/L in the patient in question reflects an elevation of more than ten times the normal value. The patient is thus likely suffering from `biliary atresia\'.', 'role': 'assistant'}]