Characterization of HBeAg-negative chronic hepatitis B in western Brazilian Amazonia

Abstract

The present study was conducted with 55 patients native from western Brazilian Amazonia, who were HBV-DNA positive after seroconversion of HBeAg. It is a descriptive case study, with the patients separated into two groups: with hepatitis and without hepatitis on histological examination. The aim of the present study was to describe the clinical and molecular characteristics of patients who are chronic carriers of HBsAg. The prevalence of hepatitis was 63.64%, with a predominance of males (41.82%) and a mean age of 42.5 years, occurring mostly in natives of the southeast sub-region (32.73%). Time was a variable proportional to the course of the disease and the most frequent symptoms were: dyspepsia, asthenia and loss of libido with the majority of the patients having history of prior contact with HBV or positive family history. Splenomegalia was the most frequent sign (40%). Among the tests, platelet count, serum albumin and prothrombin activity were significant in the diagnosis of hepatitis. Alphafetoprotein was greater in patients with hepatitis, and hepatocellular carcinoma was detected in 3.63% of the patients with hepatic cirrhosis. Three types of HBV genotypes were diagnosed: A, D and F in the samples amplified for gene S. Genotype A (AA) was observed in 54.54% of the cases with hepatitis, in contrast to other studies showing the predominance of genotype F in this region. We observed mutations in 36.36%, with a predominance of the mutations in the core promoter region (31.81%), due to the greater prevalence of genotype A in this study. Key-Words: HBeAg-negative chronic hepatitis B, western Brazilian Amazonia, mutations.Western Brazilian Amazonia is considered a region of high endemicity for hepatitis B virus (HBV), where a large part of the population is infected in perinatal period and during infancy. The prevalence of chronic carriers of HBV surface antigen (HBsAg) in these areas varies between 5% and 15% and approximately 50% to 95% of the population show serologic evidence of past infection with HBV [1,2,3]. Various factors are implicated in the development and outcome of HBV infection, but the progression to chronic hepatitis is proportionally greater in individuals infected by the vertical route or during the perinatal period [4]. Chronic hepatopathies related to HBV are seen in two forms: HBeAg positive and HBeAg negative. The HBeAg-negative chronic forms are represented by two groups of patients: chronic inactive HBsAg carriers and chronic hepatitis B (CHB) patients. The distinction between these two forms is difficult, particularly in patients with biochemical and intermittent virologic activity. It is estimated that in the world there are approximately 350 million inactive HBsAg carriers, and of these, 7% to 30% are infected with mutant forms of HBV, which despite the presence of anti-HBe antibody continue to be HBV-DNA positive [5]. Chronic HBsAg carriers who show HBeAg-negative/antiHBe-positive serologic status and have serum HBV-DNA detectable by PCR and active hepatic disease characterized by ...

Molecular epidemiology of hepatitis B virus among the indigenous population of the Curuçá and Itaquaí Rivers, Javari Valley, State of Amazonas, Brazil

“…The results of this study confirm the high prevalence of HBV-DNA, estimated at 51.1%, in the indigenous communities of the Curuçá and Itaquaí Rivers in the Javari Valley of Amazonas state. This information is in line with other findings in which similar prevalence figures were found 16,17 . Barros-Junior et al 18 reported a lower prevalence in 51 (17.6%) patients of the Brazilian Amazon.…”

“…This goes against some studies that indicate greater prevalence among men 17,19 and other studies that show a higher caseload among women 22 . It is the view of the researchers, however, that men are probably more exposed to sources of infection due to behavioral aspects such as drug use, promiscuity, infrequent prophylactic use, greater frequency of travel outside of the indigenous areas, and decorative body piercings.…”

Molecular characterization of the hepatitis B virus in autochthonous and endogenous populations in the Western Brazilian Amazon

“…Studies on the distribution of HBV genotypes in Brazil and the Amazon also show that in the northern region, genotype A is the most common, followed by genotype D and genotype F 12,[17][18][19] . However, other studies performed in the Brazilian Amazon revealed that genotype F is more prevalent [20][21][22] .…”

“…We believe that this difference could be associated with the type of samples evaluated; while our samples were from a populationbased prevalence study, including asymptomatic individuals, the majority of the studies' published samples were usually derived from patients with established chronic disease or from patients with fulminant hepatitis 21,23 .…”

Correlation between Hepatitis B Virus Genotypes and Clinical Outcomes

“…A significantly higher number of patients infected with genotype A or D were found to be anti-HBe-positive, and among the anti-HBe-positive patients, those infected with genotype D had significantly higher alanine transaminase (ALT) levels (25).…”