Clinical Significance of Persistently Normal ALT in Chronic Hepatitis B Patients

Levels of the liver enzyme alanine aminotransferase (ALT) are often measured as an indicator of liver health. However, elevated ALT is a sign of liver inflammation, and may not be a good reflection of fibrosis progression.

As reported in the December 200 Journal of Hepatology, researchers aimed to determine whether normal ALT is associated with liver injury in a cohort of chronic hepatitis B patients undergoing liver biopsy.

In this retrospective review, 192 participants were divided into 3 groups:

• Persistently normal ALT (n = 59);

• ALT 1 to 1.5 times the upper limit of normal (x ULN) (n = 26);

• ALT > 1.5 x ULN (n = 107).

Results

• Increasing age, higher ALT, higher grade of inflammation on biopsy, and HBeAg positive status were predictors of liver fibrosis.

• 18% of patients with persistently normal ALT had at least moderate fibrosis (stage F2 or higher) and 34% had grade 2 or 3 inflammation.

• Overall, 37% of patients with persistently normal ALT had significant fibrosis or liver inflammation.

• Subgroup analysis showed that the majority of patients with fibrosis belonged to the high normal ALT group.

• Only a minority who were young and immune tolerant had significant findings on biopsy.

Conclusion

In conclusion, the authors wrote, “There is significant fibrosis and inflammation in 37% of patients with persistently normal ALT and a liver biopsy should be considered in patients older than 40 with high normal ALT.”

01/04/08

References
M Lai, BJ Hyatt, I Nasser, and others. The clinical significance of persistently normal ALT in chronic hepatitis B infection. Journal of Hepatology 47(6): 760-767. December 2007.