In whole study, there were totally 65.2% with G≥2, 52.2% with S≥2, even 9.3% with early cirrhosis. The histopathological alterations of liver were similarly with research of Kumar M et al (10) and Gui HL et al (14). Previous studies had shown CHB patients with PN-ALT had definitively increased risk of long-term cirrhotic complications and HCC (15, 16). Although there was no consensus on treatment for chronic HBV-infected cases with PN-ALT, early interventions were needed in patients before it progressed to cirrhosis or liver cancer. The current international guidelines for the management of HBV recommended regularly monitor indications mostly the same for chronic HBV-infected, mainly based on serum HBV DNA, ALT levels, the severity of the liver diseases by non-invasive testing and so on (2–5). In addition to, Age was another essential factor, it had been agreed upon in current international guidelines. The most remarkable finding of the present study revealed that recommendations for patients younger than 30 years of age.
In HBeAg-positive infection phase generally with higher HBV-DNA levels and younger age than HBeAg-negative. Chen YC et al (17) concluded patients with HBeAg seroconversion before age 30 had excellent prognosis. In that study, patients with HBeAg seroconversion after age 40 were at significantly higher risk for HBeAg negative hepatitis, cirrhosis, and HCC. That seemed to explain why such high prevalence of liver histopathological abnormalities occurred in our study. In our cohort, the average age of HBeAg-positive patients was younger than HBeAg-negative, 34.4 versus 42.4 years, respectively. This indicated that the age of HBeAg serological conversion was about 40 years old, whereas underlying liver histological changes had occurred in this population, about 60% of HBeAg-positive and 70% of HBeAg-negative patients occurred liver damage, respectively.
At present research, there was a negative relationship in HBeAg-positive patients between serum viral levels and hepatic histopathological alterations, which was consistent with Xie Q et al study (18). In their study showed that patients with HBV DNA levels < 4 log10 IU/ml all had significant fibrosis, whereas the prevalence of significant fibrosis decreased to 35.9% in patients with HBV DNA level ≥7 log10 IU/m. Previous studys had shown a positive relationship between HBV DNA levels and liver fibrosis or inflammation among HBeAg-negative patients (19, 20), our study was inconsistent with that. This might be related to the small sample size. Although the HBeAg-negative HBV-infected patients were older, asymptomatically about 30-40 years, the spontaneous recovery was rare and the long-term prognosis was poor with rapid evolution to cirrhosis and HCC, the annual incidence of cirrhosis was 8–10% (21–22). Therefore, it might reveal that antiviral therapy was needed to all HBeAg-negative HBV-infected patients with PN-ALT without regard to serum viral levels.
Persistent viremia increasing the risk of cirrhosis and Hepatic carcinoma cell had been well documented in a number of studies. The maximal suppression of HBV-DNA as early as possible could reduce the risk of disease progression (23, 24). At our research, we investigated the relationships between clinical variables and hepatic pathology in HBeAg-positive patients. We used ROC to identify the optimal cut-off value of HBV-DNA that reflects obvious hepatic inflammation and fibrosis in HBeAg-positive patients, the value was 6.7 log10 IU/ml, it also reflected the lower limit of viral load of the IT phase. Although the sensitivity and specificity are not perfect, they could guide the clinician in deciding whether to initiate antiviral therapy or more closely followed up. Yenilmez E et al (25) thought HBV-DNA levels between 106 and 108 IU/mL more likely to be in chronic infection stage in HBeAg-positive CHB. Chinese Xie Q’s team (18) study also found the optimal serum HBV DNA cut-off value to evaluate low risk of significant fibrosis was ≥ 6.7 log10 IU/ml, patients with serum HBV DNA levels ≥ 8.5 log10 IU/ ml all had no significant fibrosis.
Studies had shown that using such a definite HBV-DNA cut-off value for treatment was inappropriate, needing to combine with age. At present study, the histopathological inflammation and fibrosis not correlated with age in HBeAg-positive cases, which seemed to be at odds with previous research, in those studies, age was associated independently with significant fibrosis in HBeAg-positive patients (10, 26). This might be related to small number of the population in our study. Andreani et al revealed the median age of loss of tolerance was 30.7 years (27). In Asian countries, most of HBV infection was acquired during the perinatally/early childhood period, and the onset of IT at age 30 or older indicated a prolonged status of infection and might predispose to complications. It had been reported that HBeAg-positive patients over age 30 with generally higher HBV-DNA levels were at significantly higher risk of developing HCC (11). Vlachogiannako’s review suggested that HBeAg-positive patients over 30 years old with vial load more than 20,000 IU/mL should be treated without regard to ALT levels or liver histology (28).
Patients were usually young age during IT stage. The recent Turkish study focused on naive, male and young population. The average age was 22.91 years. All cases, 53.5% had significant fibrosis, 34.4% had significant inflammation (25). As in this study, patients with HBV-DNA > 2×108 IU/mL, the most frequent Fibrosis score was 2 (46.1%), HAI was 4 (22.1%). However, the drawback of this study was that it was highly selective among the population. From our decision tree, patients younger than 30 years of age, HBV-DNA ≥ 6.7 log10IU/ml showed insignificant liver’s inflammation in 65% and insignificant fibrosis in 70%. This is at least a 10% improvement over age and ALT alone in identifying liver tissue damage.
According to guidelines, there was controversial to decrease the treatment threshold for ALT level. And in the literature, high risk of liver fibrosis in HBeAg-positive patients with an ALT level > 0.5 ULN (ULN, 58 IU/L) (29). Lai M et al reported that ALT levels between 25-40 U/L was regarded as high normal, in which histopathological abnormalities were more likely to occur (30). It was clear from the literature mentioned above that the decision to initiate antiviral therapy should not be based on a specific ALT threshold. However, lowering the ALT threshold was worthwhile. According to decision tree, patients younger than 30 years of age, who HBV-DNA levels ≥ 6.7 log10 IU/ml showed 67% were insignificant liver inflammation, 75% were insignificant fibrosis with ALT ≤ 25U/L. This suggested that the evaluation of liver tissue changes in chronic HBV-infected patients under 30 years old was mainly based on the virus level, pathological abnormalities could be further defined by adding the ALT level.
There were several limitations in our study, it's a retrospective, single-center study, with small sample size, existing unavoidable selective bias. At the same time, the cross-sectional span was relatively long, almost nearly 20 years. In the past, ALT was the main indicator for antiviral treatment of CHB, the data was complete, and patients lock of other indicators' data, so we did not include more serological indicators.
In conclusion, it usually required to consider age, viral loads and ALT levels comprehensively when evaluating histopathological abnormality of liver. For chronic HBV-infected patients whose age ≤ 30 years old with PN-ALT and HBeAg-positive, patients with HBV-DNA lower than 6.7 log10 IU/ml should perform liver biopsy to assess the severity of the disease. For patients whose HBV-DNA >6.7log10IU/ml, histology could be further assessed in conjunction with ALT, 25U/L seemed the considerable threshold. The majority of chronic HBV-infected patients with PN-ALT with HBeAg-negative had severe liver histopathological damage, timely viral therapy was necessary.