Re-evaluation of the Serum Alanine Aminotransferase Upper Normal Limit in Chronic Hepatitis C Patients

Abstract

The aim of this study was to re-evaluate the upper limit of normal range (ULN) for serum alanine aminotransferase (ALT) in chronic hepatitis C (CH-C) patients who achieved sustained virological response (SVR) to interferon therapy. Enrolled in this study were 136 consecutive patients, 84 males and 52 females, mean age 52.1+/-14.8 years, with CH-C who received interferon therapy during 1992 to 2008 and achieved SVR. AST and ALT levels (3 serial measurements) were measured every 3 to 4 months over one year after termination of interferon therapy and then the measurements were averaged for each patient. The distribution of AST and ALT showed normal distribution. Overall, AST levels were 19.7+/-3 IU/L and ALT levels were 13.8+/-3.1 IU/L in all patients, AST levels were 19.8+/-3 IU/L and 12.9+/-2.9 IU/L and ALT levels were 14.4+/-3.2 IU/L and 9.9+/-3.5 IU/L in male and female patients, respectively. AST level was the highest in the 6th decade and ALT level was in the 5th decade. In this study on CH-C patients with SVR to interferon therapy, ULN of serum ALT and AST were far lower than the current accepted value. We propose that a suitable ULN of serum AST is <25 IU/L and ALT is <20 IU/L in CH-C patients.