The work aimed to compare two methods of determining aminotransferases with and without adding pyridoxal phosphate (PLP). It was found that the data did not follow the normal distribution (p>0.05); that the difference between means was statistically significant (p<0.0001) and that the relationship was positive linear (r>0.967, p<0.0001). The agreement was 95% for aspartate aminotransferase (AST) and 93-94% for alanine aminotransferase (ALT). The variation of ALT activity with PLP was: 11.13 IU/L (95%CI: 7.99-14.28), 6.44 IU/L (95%CI: 4.35-8.52) and 8.76 IU/L (95%CI: 6.85- 10.67) and the variation of AST was: 10.86 IU/L (95%CI: 4.63-17.08), 8.08 IU/L (95%CI: 5.06-11.10) and 9.36 IU/L (95%CI: 6.12-12.61) for men, women and both sexes, respectively. In conclusion, it was shown that PLP overestimated the activity of both enzymes.
