RESUMEN
<p><b>OBJECTIVE</b>To investigate the dynamic quantitative changes in expression of hepatitis B virus (HBV) surface antigen (HBsAg) that occurs during the natural recovery course and the short-term antivirus treatment period of patients suffering from flares in chronic hepatitis B (CHB).</p><p><b>METHODS</b>CHB patients presenting for treatment of flare-ups were randomly assigned to receive treatment with Entecavir antiviral (group A, n = 39) or to naturally resolve the acute condition (group B, n = 22). All patients MELD scores were calculated and HBsAg levels and HBV DNA loads were measured upon admission (baseline), at worst-condition stage, and end of treatment/flare-up (discharge). Pairwise comparisons of intergroup differences were made to evaluate the change in the three disease parameters over time in response to the management approach.</p><p><b>RESULTS</b>The levels of HBsAg were not significantly different between the two groups at baseline, worst-condition stage and discharge (group A: (3.68+/-0.45), (3.84+/-0.19) and (3.69+/-0.58) log10 cut-off index (COI) respectively; group B: (3.59+/-0.54), (3.47+/-0.76) and (3.43+/-0.68) log10 COI respectively; all P more than 0.05). However, the HBV DNA loads were significantly lower in group A than in group B at the worst-condition stage and at discharge (all P less than 0.05). In group A, the MELD scores were significantly higher at baseline and at worst-condition stage than at discharge (all P = 0.000), but the difference between baseline and worst-condition stage was not significant. Also in group A, the HBV DNA load showed a gradually decreasing trend over time (baseline more than worst-condition stage more than discharge, all P less than 0.05). No significant differences were observed over time in the HBsAg levels of group A. In group B, the MELD scores were significantly higher at baseline and at worst-condition stage than at discharge (all P = 0.000), but the difference between baseline and worst-condition stage was not significant (P = 0.619). Also in group B, the HBV DNA loads were significantly higher at baseline and worst-condition stage than at discharge (P = 0.000 and P = 0.003 respectively), but the difference between baseline and worst-condition stage was not significant. Finally, no significant differences were observed over time in the HBsAg levels of group B.</p><p><b>CONCLUSION</b>Natural recovery from an acute flare-up of CHB is not accompanied by a change in HBsAg levels. In addition, short-term antiviral treatment to resolve the flare-up has no influence on HBsAg level.</p>