GPT and obesity due to melanocortin 4 receptor deficiency: The fluctuations of aminotransferases alter their usefulness in diagnosing fatty liver disease since it was proven that children with obesity associated with NAFLD or non-alcoholic steatohepatitis (NASH) might have normal levels of aspartate aminotransferase (AST) or alanine aminotransferase (ALT) over time [14].