Background: Chronic hepatitis B virus infection (HBV) may reactivate during the course of the disease and is called spontaneous relapse. The purpose of this study was to evaluate the incidence of relapse of hepatitis in subjects with inactive HBV carriers.
Methods: This follow-up study was performed on 785 patients with inactive HBV carriers that were followed-up at six month intervals. The presence of serum HBsAg and anti-HBe, without HBeAg, HBV DNA levels <2000 IU/ml with normal alanine aminotransferase (ALT) levels was defined as inactive carriers. Patients who developed ALT ≥80 IU/L with HBV DNA levels ≥2000 IU/ml were considered as spontaneous relapse.
Results: Seven hundred- eighty five cases (441 males, 344 females) of chronic HBV infected individuals were followed-up. The mean age at the entrance of the study was 30.5±11.8 years. The mean follow-up duration was 5.9±5 years. Relapse was seen in 35 (4.5%) cases,  in 27 out of 441 (6.1%) males and in 8 out of 344 (2.3%) females and in 4.2% subjects ≥ 30 years versus in 4.7% cases of under 30 years (p>0.05). The development of relapse in males was higher than females (hazard ratio 2.53, 95% CI 1.2-5.6, p=0.021), but age ≥30 or < 30 years did not have effect (hazard ratio1.21, 95% CI 0.62-2.36, p=0.58).
Conclusions: The results show that spontaneous relapse of hepatitis may develop during the course of chronic HBV infection. We suggest that all patients with chronic hepatitis B, regardless of their age, be examined for the possibility of relapse.