Prognostic Values of Fluctuations in Serum Levels of Alanine Transaminase in Inactive Carrier State of HBV Infection

BACKGROUND: Current guidelines introduce periodic monitoring of serum alanine transaminase (ALT) as the first-line modality in follow-up patients, with a hepatitis B virus (HBV) inactive carrier state. OBJECTIVES: This study aimed to determine the incidence rate and patterns of ALT fluctuations and prognostic values for the development of chronic HBV e antigen (HBeAg)-negative hepatitis B (CHB), HBV surface antigen (HBsAg) seroclearance, and liver-related complications. PATIENTS AND METHODS: Treatment-naïve patients with a chronic HBV infection, HBeAg(-)/HBeAb(+), normal ALT levels, and HBV DNA < 2000 IU/mL, were followed-up every 6-12 months by assessing serum ALT levels. Serum HBV DNA was measured in cases of elevated ALT levels. RESULTS: A total of 399 patients were followed-up for 8.9 years; ALT > upper limit of normal (ULN, i.e. 40 IU/L) was detected in 103 (25.8%) patients, with an annual incidence rate of 2.9%. ALT elevation was associated with; male gender, age, and higher serum ALT levels at study entry. Among the cases of ALT elevations, 16 (15.5%) patients had ALT levels > 2 × ULN. There were 38 (36.9%) patients who had ALT levels that remained > ULN over six months, and 21 (20.4%) patients experienced at least two episodes of ALT elevations. In 15 (14.6%) patients, elevated ALT levels were associated with increased HBV replication (i.e. HBV DNA > 2 000 IU/mL) and these were considered as CHB. However, elevation of ALT levels, even in the absence of HBV replication, increased the risk for the development of CHB up to 8-fold in prospective follow-ups. HBsAg seroclearance, cirrhosis, and hepatocellular carcinoma were detected in 43 (10.8%), 4 (1%), and 1 (0.25%) patients, respectively. CONCLUSIONS: Fluctuations in serum ALT levels may change the prognosis of a HBV inactive carrier state.