 A combination of liver function tests as well as other physical exam findings is essential to arrive at a diagnosis.Some bone and heart disorders can lead to an increase in ALP and the aminotransferases, so the first step in differentiating these from liver problems is to compare the levels of GGT, which will only be elevated in liver-specific conditions.The second step is distinguishing from biliary (cholestatic) or liver causes of jaundice and altered laboratory results.