Hepatitis B virus infection among institutionalized mentally ill patients in Brazil

Occult hepatitis B virus infection in patients with chronic liver disease of different etiology in a Brazilian referral center: comparison of two different hepatitis B virus deoxyribonucleic acid amplification protocols: a cross-sectional study

BACKGROUND

Occult hepatitis B virus infection (OBI) is defined as the presence of hepatitis B virus (HBV) deoxyribonucleic acid (DNA) in the liver of individuals with undetectable hepatitis B virus surface antigen (HBsAg) in the serum. The actual prevalence of OBI and its clinical relevance are not yet fully understood.

OBJECTIVE

To evaluate the prevalence of HBV DNA in liver biopsies of HBsAg-negative patients with chronic liver disease of different etiologies in a referral center in Brazil and compare two different HBV DNA amplification protocols to detect HBV.

DESIGN AND SETTING

This cross-sectional observational study was conducted at the Liver Outpatient Clinic, Hospital das Clínicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil, between January 2016 and December 2019.

METHODS

HBV DNA was investigated in 104 liver biopsy samples from individuals with chronic liver disease of different etiologies, in whom HBsAg was undetectable in serum by nested-polymerase chain reaction (nested-PCR), using two different protocols.

RESULTS

OBI, diagnosed by detecting HBV DNA using both protocols, was detected in 6.7% of the 104 individuals investigated. Both protocols showed a good reliability.

CONCLUSION

In addition to the differences in the prevalence of HBV infection in different regions, variations in the polymerase chain reaction technique used for HBV DNA amplification may be responsible for the large variations in the prevalence of OBI identified in different studies. There is a need for better standardization of the diagnostic methods used to diagnose this entity.

Occult Hepatitis B virus (HBV) infection and challenges for hepatitis elimination: A literature review

Occult hepatitis B infection (OBI) is characterized by the detection of hepatitis B virus (HBV) DNA in serum or liver but negativity for hepatitis B surface antigen. OBI, which is thought to be maintained by host, immunological, viral and/or epigenetic factors, is one of the most challenging clinical features in the study of viral hepatitis. Currently, there is no validated detection test for OBI. It is believed that OBI is widely distributed throughout the world, with a higher prevalence in populations at high-risk HBV, but the detailed worldwide prevalence patterns are unknown. We conducted a survey of recently published studies on OBI rates across all continents. High prevalence rates of OBI are observed in some specific groups, including patients with hepatitis C virus, human immunodeficiency virus co-infection or hepatocellular carcinoma. In 2016, the World Health Organization adopted strategies to eliminate viral hepatitis by 2030, but the difficulties in detecting and treating OBI currently challenge this goal. Subjects with OBI can transmit HBV, and episodes of reactivation can occur. Further studies to understanding the mechanisms that drive the development of OBI are needed and can contribute to efforts at eliminating viral hepatitis.

[Hepatitis B Virus (Hepadnaviridae: Orthohepadnavirus: Hepatitis B virus) among Hospitalized Mentally Disabled Patients is not transmitted by their nurses or family members]

BACKGROUND

Prevalence of hepatitis B virus (HBV) infection has been reported to be higher in the institutionalized mentally disabled patients than that of the general population previously reported in Iran. This study aims to investigate HBV infection among nurses and families of the hospitalized mentally disabled patients.

MATERIAL AND METHODS

This study was conducted on 110 nurses and family members of the mentally disabled patients who were hospitalized in five residential care centers of Tehran. The presence of hepatitis B surface antigen (HBsAg) and hepatitis B core antibody (HBcAb) was examined using the enzyme-linked immunosorbent assay (ELISA). Afterwards, HBV DNA was extracted, and then propagated via a nested polymerase chain reaction (PCR) and specific primers. Finally, a phylogenetic tree was constructed using the neighbor-joining method to compare virus genomes in the nurses' serum with other isolated HBVs worldwide.

RESULTS

Out of 102 studied nurses, three (3%) were positive for HBsAg (100% female). Also, no patient was positive for the HBV genome, while eight (7.3%) nurses were positive for HBcAb including two (25%) males and six (75%) females. Genome sequencing of one DNA positive sample showed that the isolated virus from this patient contained sub genotype D1 and subtype ayw2. The results of none of the family members were positive for HBsAg, HBcAb, or HBV DNA.

CONCLUSION

This study showed a higher prevalence of HBsAg among nurses (3%) compared to the Iranian general population (1.7-2.1%). The virus isolated from the nurses belonged to subgenotype D1 and subtype ayw2 in accordance with previous Iranian reports. Also, there was no drug-resistant or vaccine-escape mutations in the obtained viral genome. Moreover, low immune pressure on the virus in the asymptomatic chronic HBV patients might be responsible for low nucleotide divergence among the derived HBV genome.