Revising the upper limit of normal for levels of serum alanine aminotransferase in a Middle Eastern population with normal liver histology

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.To evaluate the ALT concentrations in a healthy Middle Eastern population with biopsy-proven normal liver tissue.ALT values were calculated from 175 consecutive Saudi potential living liver donors who underwent a liver biopsy as part of a stepwise pretransplant workup.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 (p0.0001). Moreover, when we analyzed donors according to the Prati criteria, 63 (36.0 %) of the individuals were classified into this subgroup. The mean ALT concentration was 12.9 U/l ± 4.5 in women and 19.7 U/l ± 6.9 in men, and these values were significantly lower than those obtained from subjects who did not fit the Prati criteria (19.4 U/l ± 1.8, p = 0.04 for women and 29.0 U/l ± 12.1, p =0.0001 for men). Thus, we calculated healthy ALT values of 33 IU/l for men and 22 IU/l for women.The ULN for ALT levels in Middle Eastern populations should be lowered, including separate values for males and females. Furthermore, metabolic parameters were shown to have a significant effect on ALT levels.