ABSTRACT
Initial laboratory investigations of an individual with abnormal liver biochemical results should include a complete blood count with differential and a serum electrolyte panel, including fasting plasma glucose and serum creatinine levels. The liver profile itself should include determination of: serum aspartate (AST, formerly SGOT) and alanine (ALT, formerly SGPT) aminotransferases, total and direct bilirubin, and alkaline phosphatase. Prothrombin time (PT or international normalized ratio [INR]) and albumin are useful to characterize hepatic synthetic function. Other blood tests that are essential in the initial
evaluation of persistently abnormal liver biochemical findings include fasting iron, total iron binding capacity (TIBC), and ferritin to exclude hemochromatosis; ceruloplasmin to screen for Wilson’s disease; 1-antitrypsin phenotype studies to exclude 1-antitrypsin deficiency; antinuclear antibody (ANA), anti-smooth muscle antibody (ASMA), and - globulin level by serum protein electrophoresis to screen for autoimmune hepatitis; antimitochondrial antibody (AMA) to screen for primary biliary cirrhosis; and hepatitis serological evaluations (discussed later). An increasingly frequent diagnosis to which persistently abnormal liver biochemical results are attributed is nonalcoholic steatohepatitis (NASH), also referred to as nonalcoholic fatty liver disease. No specific serum marker currently exists to identify NASH; however, central obesity, hyperlipidemia, and noninsulin-dependent diabetes mellitus are frequently associated with this disorder.
