Re-evaluation of the serum alanine aminotransferase upper normal limit in chronic hepatitis C patients.

ABSTRACT

OBJECTIVE: 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. METHODS: 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. RESULTS: 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. CONCLUSION: 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.