Question
Why would a four-month-old baby’s alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels be elevated?
Answer
It is not necessarily a sign of liver disease. Newborns, due to the breakdown of a large number of red blood cells and the incomplete development of the liver enzyme system, may experience physiological jaundice. Typically, alanine aminotransferase levels are about double those of adults shortly after birth and gradually decrease to adult levels between 5 months and 1 year. Therefore, an elevated aspartate aminotransferase level is not necessarily indicative of liver disease.