Patients with HBeAg-positive chronic hepatitis B usually present in the third or fourth decade of life. Men outnumber women, 1415 liver damage ranges from mild (24 to 42%) to moderate or severe chronic hepatitis (44 to 63%) or active cirrhosis (10 to 24%) 1617181920. Chronic hepatitis B tends to be milder in children. Nevertheless, severe liver disease including cirrhosis may occur in a small proportion of patients during childhood 2122. A key event in the natural history of HBeAg positive chronic hepatitis is HBeAg seroconversion. Several studies have shown that seroconversion with marked reduction of HBV replication is associated with biochemical and histologic remission of inflammatory activity in the majority of patients 232425. Regression of fibrosis occurs gradually months to years after HBeAg seroconversion.26 In longitudinal studies the observed probability of clearing HBeAg was about 50% and 70% within 5 and 10 years of diagnosis, respectively 23272829. Most studies have found that the mean annual rate of spontaneous HBeAg seroconversion ranges from 8 to 15% in children or adults with elevated ALT 3423242529303131. Among Asian, most of whom have normal ALT, spontaneous HBeAg seroconversion occurs at a very low rate, less than 2% during the first 3 years of age and 4 to 5% in children older than 3 years 32. Several determinants for HBeAg seroconversion have been reported, including gender, age, ALT level, and more recently HBV genotypes. Older carriers and females are more likely to clear HBeAg 33.

Frequent acute exacerbation of hepatitis, reflecting immune-mediated lysis of HBV-infected hepatocytes with ALT elevations to more than 10 times ULN and more than twice the baseline value and with HBV DNA levels rising before and falling during the flare, precede seroconversion of HBeAg to anti-HBe. These exacerbations usually last 2 to 4 months 34. In some cases these spontaneous flares of hepatitis are not followed by subsequent HBeAg seroconversion and can be viewed as an abortive attempt at seroconversion. These flares of hepatitis are usually asymptomatic and frequently unrecognized, but some are accompanied by symptoms of acute hepatitis and rarely, primarily in patients with cirrhosis or advanced fibrosis, may lead to hepatic decompensation and even death due to massive necrosis 34.

The diagnosis of HBeAg-negative chronic hepatitis B is based on the presence of HBsAg for more than 6 months, undetectable HBeAg, presence of anti-HBe, detectable serum HBV DNA exceeding 10⁵ to 10⁶ copies/mL, increased ALT levels, and hepatic necroinflammation on histology. Other causes of liver disease, such as superinfection with other hepatitis viruses, alcohol abuse, hepatotoxic drug use, and autoimmune or metabolic liver disease, should be excluded 34. The atypical serological profile is related to the predominance of HBV variants, which are unable to express HBeAg. The most frequent variant has a G-to-A change at nucleotide 1896 (G1896A), which creates a stop codon in the precore region of the HBV genome and completely abolishes the production of HBeAg 35. Other variants include changes in the start codon of the precore region or a two-nucleotide substitution (A1762T, G1764A) in the core promoter region, which reduces precore messenger RNA synthesis and HBeAg production 36.

Patient with HBeAg negative are older than patients with HBeAg-positive chronic hepatitis (median 40, range 36–45 years). Males predominate and data indicate that liver disease is more active and advanced, minimal or mild chronic hepatitis is infrequent, and severe necroinflammation is seen in more than 50% patients at diagnosis 373839. In reports from Mediterranean area, 29 to 38% had cirrhosis at presentation. The older age and the high rate of advanced liver damage at presentation suggest that HBeAg-negative chronic hepatitis represents a late phase in the natural history of chronic HBV infection rather than de novo infection with HBV variants that do not produce HBeAg. To further support this concept, a recent long-term study reported that HBeAg-negative chronic hepatitis accumulated over time after HBeAg seroconversion with a cumulative incidence of approximately 25% after 16 years of follow-up 40. Thus, the increasing prevalence of HBeAg-negative. Fluctuation in level of viremia and ALT are more common and sustained response is rare. Delayed spontaneous HBsAg clearance has been estimated to occur at a low rate of 0.5% per year 40.

Inactive carriers forms the largest group in chronic HBV infected patients. Around 300 million people are inactive carriers The inactive HBsAg carrier state is diagnosed by absence of HBeAg and presence of anti-HBe, undetectable or low levels of HBV DNA in PCR-based assays, repeatedly normal ALT levels, and minimal or no necroinflammation, slight fibrosis, or even normal histology on biopsy 34. Inactive cirrhosis may be present in patients who had active liver disease during the replicative phase of infection. The prognosis of the inactive HBsAg carrier state is usually benign. Long-term follow- up (up to 18 years) of these carriers has indicated that the vast majority show sustained biochemical remission and very low risk of cirrhosis or hepatocellular carcinoma (HCC) 404142. Rarely, patients, even noncirrhotics, may develop liver cancer during the inactive HBsAg carrier state 40414243. In addition, approximately 20 to 30% of persons in the inactive HBsAg carrier state may undergo spontaneous reactivation of hepatitis B during follow-up 29333440. Multiple episodes of reactivation or sustained reactivation can cause progressive hepatic damage and even hepatic decompensation. HBV reactivation is usually asymptomatic but on occasion can mimic acute viral hepatitis 44. Acute flares of hepatitis should be differentiated from superinfection with other hepatotropic viruses. As many as 20 to 30% of these acute exacerbations may be caused by superinfection with HDV, HCV, or hepatitis A virus and can be associated with an increased risk of fulminant hepatic failure 44. Some carriers eventually become HBsAg negative and develop anti-HBs. The incidence of delayed HBsAg clearance has been estimated to be 1 to 2% per year in Western countries, where HBV infection is usually acquired in adulthood, but a lower rate from 0.05 to 0.8% per year in endemic areas, where HBV infection is mostly acquired perinatally or in early childhood. Clearance of HBsAg has been reported to be higher in women than in men and in older than younger carriers. Prognosis is improved by loss of HBsAg as liver disease is usually inactive and nonprogressive, but HBsAg clearance does not completely prevent occurrence of decompensation or HCC in patients who have already developed cirrhosis 4546.

HBV infection is termed as chronic if it continues to be HBsAg +ve for ≥6 months. Chronic HBV infection is a dynamic process with a wide spectrum of spectrum of affliction. On one hand patients are asymptomatic with no clinical evidence of liver diseases, while on other being end-stage cirrhosis and hepatocellular carcinoma. For many decades the patients were considered to have a benign, non progression infection and were designated as hepatitis B "carriers". Probably the word 'carrier' was mistakenly chosen for hepatitis B as in true sense, a carrier is an individual who (i) harbors a specific infectious agent (ii) has no discernible clinical disease and (iii) serves as a potential source of infection. For this infection the second and third points should be looked at carefully. One the basis of Asian collaborative survey the term 'carrier' was replaced by the term 'chronic hepatitis B virus infection' 4748. Later on for this infection the term 'Inactive HBsAg carrier' was adopted 49.