Prevalence of occult hepatitis B virus infection in hemodialysis patients in Isfahan, Iran

M133S mutation possibly involve in the ER stress and mitophagy pathway in maintenance hemodialysis patients with occult hepatitis B infection

Occult hepatitis B virus infection (OBI) is characterized by the presence of HBV DNA in the absence of detectable HBsAg. OBI is an important risk factor for cirrhosis and hepatocellular carcinoma, but its pathogenesis has not been fully elucidated. Mutations in the HBV preS/S genes can lead to impaired secretion of either HBsAg or S-protein resulting in the accumulation of defective viruses or S protein in cells. In our previous work, the M133S mutation was present in the HBV S gene of maintenance hemodialysis (MHD) patients with OBI. In this study, we investigated the potential role of amino acid substitutions in S proteins in S protein production and secretion through the construction of mutant S gene plasmids, structural prediction, transcriptome sequencing analysis, and in vitro functional studies. Protein structure prediction showed that the S protein M133S mutant exhibited hydrophilic modifications, with greater aggregation and accumulation of the entire structure within the membrane phospholipid bilayer. Differential gene enrichment analysis of transcriptome sequencing data showed that differentially expressed genes were mainly concentrated in protein processing in the endoplasmic reticulum (ER). The expression of heat shock family proteins and ER chaperone molecules was significantly increased in the wild-type and mutant groups, whereas the expression of mitochondria-associated proteins was decreased. Immunofluorescence staining and protein blotting showed that the endoplasmic reticulum-associated protein PDI, the autophagy marker LC3, and the lysosome-associated protein LAMP2 co-localized with the S proteins in the wild-type and mutant strains, and their expression was increased. The mitochondria-associated TOMM20 protein was also co-expressed with the S protein, but expression was significantly reduced in the mutant. The M133S mutation in the S gene is expressed as a defective and misfolded protein that accumulates in the endoplasmic reticulum causing secretion-impaired endoplasmic reticulum stress, which in turn triggers mitochondrial autophagy and recruits lysosomes to fuse with the autophagosome, leading to mitochondrial clearance. This study preliminarily demonstrated that the mutation of M133S in the S gene can cause OBI and is associated with disease progression, providing a theoretical basis for the diagnosis and treatment of OBI.

Rate of occult hepatitis B virus infection among individuals with tuberculosis in northeastern Iran: A molecular epidemiological study

One third of the world population has a history of exposure to the hepatitis B virus (HBV), and two billion people are infected with latent tuberculosis (TB). Occult hepatitis B infection (OBI) is defined as the presence of replicative-competent HBV DNA in the liver with detectable or undetectable HBV DNA in the serum of individuals testing negative for the HBV surface antigen (HBsAg). Screening with HBV DNA could identify OBI and significantly reduce carriers and complications of chronic hepatitis B (CHB). This study aims to assess HBV serological markers and OBI molecular diagnosis among people with TB in Mashhad, northeastern Iran. We have performed HBV serological markers (HBsAg, HBc antibodies (Ab) and HBs Ab) in 175 participants. Fourteen HBsAg⁺ sera were excluded for further analysis. The presence of HBV DNA (C, S, and X gene regions) was assessed by the qualitative real-time PCR (qPCR) method. Frequencies of HBsAg, HBc, and HBs Ab were 8% (14/175), 36.6% (64/175), and 49.1% (86/175), respectively. Among these 42.9% (69/161) were negative for all HBV serological markers. The S, C, and X gene regions were positive in 10.3% (16/156), 15.4% (24/156), and 22.4% (35/156) of participants, respectively. The total OBI frequency was estimated at 33.3% (52/156) when based on detecting one HBV genomic region. Twenty-two and 30 participants had a seronegative and seropositive OBI, respectively. Thorough screening of high-risk groups with reliable and sensitive molecular methods could lead to OBI identification and decrease CHB long-term complications. Mass immunization remains critical in preventing, reducing, and potentially eliminating HBV complications.

High Prevalence of Occult Hepatitis B Virus Infection among Iranian Hemodialysis Patients

Considering the potential risks associated with occult hepatitis B virus (HBV) infection, this study was designed to investigate the magnitude and genotypic pattern of occult HBV infection among hemodialysis patients. All patients on regular hemodialysis attending the dialysis centers located in southern Iran and 277 nonhemodialysis controls were invited to participate in this study. Serum samples were tested for detection of hepatitis B core antibody (HBcAb) and hepatitis B surface antigen (HBsAg) by competitive enzyme immunoassay and sandwich ELISA, respectively. The molecular evaluation of HBV infection was conducted by two nested polymerase chain reaction (PCR) assays, targeting S, X, and precore regions of HBV genome, and sequencing by Sanger dideoxy sequencing technology. Moreover, HBV viremic samples were tested for hepatitis C virus (HCV) coinfection by HCV Ab ELISA and seminested reverse transcriptase PCR. Of 279 hemodialysis patients, five (1.8%) were positive for HBsAg, 66 (23.7%) were positive for HBcAb, and 32 (11.5%) had HBV viremia with HBV genotype D, sub-genotype D3 and subtype ayw2. Moreover, 90.6% of the hemodialysis patients with HBV viremia had occult HBV infection. Hemodialysis patients (11.5%) had significantly higher prevalence of HBV viremia than nonhemodialysis controls (1.08%; P = 0.0001). The prevalence of HBV viremia among hemodialysis patients was not statistically associated with duration of hemodialysis, age and gender distribution. In contrast, HBV viremia was significantly associated with place of residency and ethnicity, with residents of Dashtestan and Arab having had significantly higher prevalence of HBV viremia compared with the residents of other cities and Fars patients. Notably, 27.6% and 6.9% of hemodialysis patients infected with occult HBV infection were also positive for anti-HCV antibodies and HCV viremia, respectively. High prevalence of occult HBV infection was detected in hemodialysis patients, whereas 62% of patients with occult HBV infection were negative for HBcAb. Therefore, screening of all hemodialysis patients by sensitive molecular tests, regardless of the pattern of HBV serological markers, is recommended to increase the diagnosis rate of HBV infection.

Prevalence of occult hepatitis B virus infection among patients receiving haemodialysis in Sana'a city

BACKGROUND

Occult hepatitis B virus infection (OBI) is a challenging entity. Due to the increase in invasive procedures, blood transfusions, and difficulties in diagnosing OBI, patients are more likely to acquire OBI. This cross-sectional study was conducted to assess the prevalence of OBI by hepatitis B virus (HBV)-DNA detection, the prevalence of HBV infection by total hepatitis B core antibody (HBcAb) detection, and the potential risk factors for HBV infection in patients receiving haemodialysis regularly.

METHODS

This study included 80 patients receiving haemodialysis regularly, without acute or chronic HBV infection. They were selected from the dialysis units in Sana'a city, Yemen from June 2016 to June 2017. Patients who were positive for hepatitis B surface antigen and hepatitis B surface antibody were excluded from this study. Blood samples were taken prior to each haemodialysis session, and serological markers of HBV were included. HBcAb was measured by enzyme-linked immunosorbent assay, and HBV-DNA was measured by polymerase chain reaction.

RESULTS

HBV-DNA was detected in four patients (5%) and HBcAb was detected in 38 patients (47.5%). There was a significant association between HBV-DNA and HBcAb in patients receiving haemodialysis regularly.

CONCLUSIONS

Patients who test positive for HBcAb should undergo additional HBV-DNA testing to allow accurate HBV screening and prevent infection of other patients.

Occult Hepatitis B Infection among Hemodialysis in Tabriz, Northwest of Iran: Prevalence and Mutations within the S Region

Regardless of the extensive screening for the detection of hepatitis B surface antigen (HBsAg), hemodialysis (HD) patients are still severely at the risk of occult hepatitis B virus infection (OBI), especially in developing countries. OBI is defined as the presence of HBV DNA with undetectable HBsAg in the liver and/or Serum. This study aims to determine the prevalence of OBI in HD patients in Tabriz Province, northwest of Iran, and inquire about the mutations in the detected HBsAg. In this cross-sectional descriptive study, ELISA method assessed serum and plasma samples of 118 HBsAg-negative patients undergoing HD treatment for HBV serological markers (HBsAg and Anti-HBc). Specific primers by nested polymerase chain reaction have been utilized to examine HBV DNA; also, direct sequencing of surface genes was carried out to characterize the viral genotypes and S gene mutations. Finally, followed by real-time PCR, the quantity of viral load in OBI-positive patients was determined. A total of 118 HD patients were included (63.6% were male and 36.4% female), with an overall mean age of 60.8 ± 12.8 years old. The prevalence of antihepatitis B core antibody (Anti-HBc) in the study population was 26.3% (31/118). Five patients (4.2%) were positive for HBV DNA and labeled OBI-positive; their plasma HBV-DNA load was less than 100 IU/ml. Following the phylogenetic analysis, the samples with OBI roughly belonged to genotype D, subtype ayw2 and only two had mutations within the S ’gene’s major hydrophilic region (MHR), including T123I, C124F, and P127T. This study reports the prevalence of OBI in the HBsAg-negative HD patients being at a rate of 4.2%, which can be a clinically vital consideration in this region. HBV serologic screening approaches need to be renewed to cover nucleic acid testing in the setting of hemodialysis and all the other high-risk groups associated with it (i.e., blood and organ donors).

Prevalence of Anti-HBc Antibodies among HBsAg Negative Individuals and Its Association with Occult Hepatitis B

Introduction  Hepatitis B virus (HBV) infection is an endemic in many Asian countries, and among the major routes of transmission, transfusion is the one that should be prevented. Occult HBV infection (OBI) is defined as the presence of HBV DNA in the absence of detectable HBsAg, with or without anti-HBV antibodies. The aim of this study was to detect the prevalence of anti-HBc total antibodies among the HB surface antigen (HBsAg) negative individuals by way of enzyme-linked immunosorbent assay (ELISA), and detect the presence of HBV DNA among the anti-HBc seropositives by polymerase chain reaction (PCR). Anti-HBs among the HBV DNA positives were also found out by enzyme-linked fluorescent assay (ELFA). Materials and Methods  A total of 910 serum samples was subjected to initial screening for HBsAg by MERILISA HBsAg ELISA kits. The anti-HB core (HBc) total antibody titer was evaluated using MONOLISA ELISA (Biorad) kits. If found negative, the samples were discarded. If found positive, the samples underwent HBV DNA testing by nested PCR. Antibody to hepatitis B surface antigen (anti-HBs) was calculated among the DNA positives by ELFA. Results  A total of 133 samples were positive for anti-HBC total antibody, resulting in an overall prevalence of 14.6%. Overall prevalence of HBV DNA among the anti-HBc seropositives was 2.2%. Conclusion  Among the three HBV DNA positive patients, two belonged to the preoperative screening group, which is an alarming situation. Screening of blood for HBsAg has reduced the incidence of posttransfusion hepatitis, but HBV still remains the major source of transfusion transmitted infection in India.

Prevalence of overt and occult hepatitis B virus infections among 135 haemodialysis patients attending a haemodialysis centre at Al-Nasiriyah city, Iraq

Background and Objectives:

The prevalence of Hepatitis B virus (HBV) infection among haemodialysis (HD) patients has been well documented. In addition to overt infection, occult Hepatitis B infection exists in which a patient who is diagnosed seronegative for Hepatitis B surface antigen (HBsAg) shows positive HBV-DNA on using more accurate molecular methods. This study aims to determine the prevalence of overt and occult HBV infection among the HD patients who had attended Al-Nasiriyah dialysis centre during a two-month period.

Materials and Methods:

Serological qualitative detection of HBsAg by rapid test (strips), enzyme immunoassay (EIA, HBsAg) and molecular (real-time polymerase chain reaction (real-time PCR)) was conducted for quantitative detection of HBV in HD patients’ serum.

Results:

The prevalence of overt HBV infection among HD patients was 3.7%. The viral load of HBV positive patients was ranging from 5.85 × 10¹ to 2.16 × 10⁶ copies/ml of serum with median (7.4 × 10⁵ copies/ml). Occult Hepatitis B was not detected in any of the seronegative HD patients (0%). Overt infection was found more in males (80%) than females (20%) (P<0.05). Similarly, infection was found to be higher among patients who had blood transfusions (80%) than those who had not (20%) with statistical significant p<0.05. Although not statistically significant, the mean duration of HD was higher among HBV positive HD patients (17.6) than HBV negative HD patients (14.3). A dual infection of HBV and HCV was not detected in this study.

Conclusion:

Nosocomial transmissions at HD centres and blood transfusion are important risk factors. Besides serological screening, real-time PCR offers a safeguard against the spread of overt and occult HBV infection and determines the viral load of the positive patients.

The prevalence of occult hepatitis B infection among the blood donors in a tertiary care hospital, Puducherry

Occult hepatitis B infection (OBI) is a cause of concern while screening the blood donors to prevent transfusion-related transmission of infection. This study was conducted to assess the prevalence of OBI using total anti-HBc by ELISA and DNA detection by real time polymerase chain reaction (PCR). The samples included were negative for HBs Ag by ELISA. Out of 1102 samples tested, 156 were positive for total anti-hepatitis B core antigen and 52/156 by real-time PCR. Overall, the prevalence was found to be 4.71% (52/1102). The results indicate that nucleic acid-based testing should be an essential part of screening procedure to prevent missing of OBI.

Systematic review and meta-analysis of HIV, HBV and HCV infection prevalence in Sudan

Viral hepatitis constitutes a global health problem; previous studies have affirmed a considerable morbidity and mortality from both acute infections and chronic complications. On the other hand, Human Immunodeficiency Virus (HIV) infection is also of known burden. Determining prevalence measures of these viruses is crucial for establishing appropriate country specific strategies regarding prevention, diagnosis, and containment. This systematic review was aimed to provide pooled seroprevalence estimates of the three viruses in Sudan. Structured review of the literature was conducted to obtain relevant studies published in both national and international databases. After assessment of quality and bias in all proposed studies, 57 prevalence studies were included. Meta-analysis was conducted for all studies and subgroup analysis was also approached. The total sample size of participants in included studies providing HIV antibodies prevalence was 15,479. Based on information retrieved from these studies, HIV prevalence ranged from 0 to 18.3% among different study populations. However, pooled prevalence estimate for HIV antibodies was 1%. Kassala, Eastern Sudan was the most endemic State (4.18%). The HBV reported seroprevalence rates ranged from 5.1 up to 26.81% among different populations and the overall pooled prevalence was 12.07%. For HCV antibodies; 2.74% was determined to be the pooled prevalence. Khartoum State was the most endemic State of both HBV and HCV with seroprevalence of 12.69% and 6.78%, respectively.Based on data reviewed and synthesized; there is no evidence for an HIV endemic in the general population of Sudan. However, both HBV and HCV seroprevalence rates are indicating otherwise. Reducing the overall burden of HIV, HBV and HCV infections will require new measures and national strategies and the recognition of the infections as one of the country's priority issues.