Revising the Upper Limit of Normal for Levels of Serum Alanine Aminotransferase in a Middle Eastern Population with Normal Liver Histology

Background Recently, the upper limits of normal (ULN) for alanine-aminotransferase (ALT) has been recommended to be lowered to ≤30 U/l in men and ≤19 U/l in women. Aim To evaluate the ALT concentrations in a healthy Middle Eastern population with biopsy-proven normal liver tissue. Methods ALT values were calculated from 175 consecutive Saudi potential living liver donors who underwent a liver biopsy as part of a stepwise pretransplant workup. Results The mean age of the 110 potential donors with normal liver histology was 27 ± 6.2 years for men and 38.6 ± 7.1 years for women. The mean body mass index (BMI) levels were 23.0 ± 3.5 kg/m 2 for men and 24.7 ± 3.25 kg/m 2 for women, and the ALT levels were higher in male patients (22.6 ± 9 vs. 16.4 U/l ± 8, p value = 0.003). Multivariate linear regression showed that BMI and sex were independent variables that were positively associated with the levels of ALT ( p