Epidemiology of occult hepatitis B infection among thalassemic, hemophilia, and hemodialysis patients

Prevalence of hepatitis B infection in the Gambian population: A narrative review of recent developments

Hepatitis B is a "silent epidemic", fifty to a hundred (50-100) times more infectious than HIV, a potentially life-threatening liver infection caused by the hepatitis B virus (HBV). HBV can cause acute and chronic infection and subsequently results in a high risk of death from cirrhosis and liver cancer. Despite the availability of a safe and effective vaccine, HBV continues to be a global burden including in The Gambia. This study reviewed the recent trends in the epidemiological characteristics of HBV in the Gambia. The researchers conducted an online literature search for primary studies on HBV prevalence published in the past two decades from Jan 1992 to Feb 2022 inclusive on Google Scholar, PubMed, and Scopus. All retrieved studies were assessed for eligibility according to specific inclusion/exclusion criteria, data completeness, and methodological coherence. We found that HBV infection prevalence is above 8% in The Gambia. Moreover, HBV is the most common cause of hepatocellular carcinoma (HCC) in Gambia. Liver cirrhosis and HCC have the highest mortality contribution among hepatitis patients, with occult HBV carriers as major culprits. Also, vaccination coverage has declined from 91% to 88% according to reports from current literature. To achieve the WHO goal of eliminating HBV by 2030, policies targeting infection transmission control among risk groups, community awareness programs, research, price reduction of drugs, mass vaccinations, and diagnostics should be urgently instituted.

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.

Hepatitis B infection among β-thalassemia major patients in Bushehr province of southern Iran

This study was performed to determine the prevalence, genotype distribution and risk factors of hepatitis B virus (HBV) infection among β-thalassemia patients. ELISA was used to detect HBsAg and HBcAb. Molecular evaluation of HBV infection was performed by nested PCR, targeting S, X and pre-C regions of the genome, and sequencing. Of 126 thalassemia patients, 4 cases (3.17%) were positive for HBsAg, 23 cases (18.25%) were positive for HBcAb, and 6 cases (4.76%) had HBV viremia with genotype D, sub-genotype D3 and subtype ayw2. HBV prevalence among thalassemia patients was not statistically associated with gender distribution, place of residency, marital status and frequency of blood transfusion. HBsAg seroprevalence was significantly higher in Afghan immigrants and patients with ALT levels of 41-80 IU/L. The prevalence of HBV viremia was significantly higher among thalassemia patients aged >20 years compared to the patients aged <20 years. Moreover, 1.59% of thalassemia patients had seropositive occult HBV infection, which was positive for HBV-DNA and HBcAb but negative for HBsAg. Considering the relatively high prevalence of occult HBV infection among thalassemia patients, there is a possibility of their contamination through donated blood. Therefore, screening of donated blood based on detection of HBsAg cannot abolish HBV transmission through blood transfusion.

Occult hepatitis B in kidney transplants recipients and donors from Western Mexico

BACKGROUND

Occult hepatitis B virus infection (OBI) is defined as the presence of hepatitis B virus (HBV) DNA in serum and/or liver from HBsAg-negative subjects. Our aim was to determine OBI frequency in serum and genomic DNA in patients undergoing renal transplant and their cognate donors in a selected population from Western Mexico.

METHODS

Blood samples were obtained from 94 donors and their cognate recipients (188 participants) before kidney transplantation. Identification of HBV DNA was carried-out by nested (S-region) and semi-nested (Pol-region) PCR in both genomic and serum DNA samples from 188 participants at pre-surgical stage and from a subset of 73 recipients at three-month follow-up.

RESULTS

HBV-DNA was not detected in either genomic or serum DNA samples from recipients or donors prior to transplantation. After three-months of follow-up, 2 out of 73 (2.7%, 95% CI: 0.9-11.9%) recipients were positive to HBV-DNA (Pol-region) in genomic DNA samples using a high sensitivity Taq DNA polymerase.

CONCLUSIONS

OBI incidence in recipients of kidney transplant may be higher than previously recognized. Detection of HBV-DNA was higher in genomic DNA than in serum samples using a high sensitivity Taq DNA polymerase. To the best of our knowledge, this is the first report regarding this specific topic in Mexicans.

Hepatitis B virus Genotypes in West Azarbayjan Province, Northwest Iran

BACKGROUND:

Infections caused by Hepatitis B are one of the world health’s most serious problems. According to assessments, nearly 500,000 to 1.2 million people die each year due to chronic hepatitis, cirrhosis of the liver and hepatocellular carcinoma. Hepatitis B is one of the diseases which can be transferred through blood and its products. Clinical importance of genotypes of hepatitis B virus and their relations with mutations are well known.

AIM:

Since epidemiological data resulting from determining genotypes and sub-genotypes of hepatitis B can help a lot in defining a vaccination plan, antiretroviral therapy, detection and prevention of diseases, genotypes of this virus in hepatitis B patients were evaluated in West Azarbaijan province.

MATERIALS AND METHODS:

In this cross-sectional study, serum samples of 100 hepatitis B patients (70 male/30 female) were taken randomly from Urmia University of Medical Sciences (UMSU) referrals, Urmia, Iran; and were tested positive for the presence of surface antigens of hepatitis B virus (HBsAg) using ELISA method. In the first method, after extracting the DNA of the virus, sequencing of S genes was carried out using Sanger method, and the sequences were aligned and edited using Bioedit software. In the next step, phylogenic analysis of the sequences was done in comparison with the reference sequences which were extracted from a gene bank, utilising Neighbour-joining assay method with CLUSTRAL W software. To ensure genotyping accuracy, the samples were tested once more, using Nested PCR method.

RESULTS:

The results were consistent with the sequence method and the dominant genotype in patients suffering hepatitis was type D. In other words, Iranian’s HBV genotypic types are homogeneous and in close coordination with each other.

CONCLUSIONS:

The results reveal that D genotype is the main genotype of HBV in West Azarbayjan province, northwest Iran. Presence of this genotype was in conformity conformed withto the low rate of acute liver diseases caused by hepatitis B chronic infection, cirrhosis of the liver and hepatocellular carcinoma.

Occult hepatitis B virus infection in Greek patients with congenital bleeding disorders

Occult Hepatitis B Infection (OBI) is a form of chronic HBV infection characterized by low level HBV DNA, without detectable HBV surface antigen (HBsAg). OBI is frequently associated with the presence of anti-HBc and in some cases also with anti-HBs. Patients, who formerly received non-inactivated factor concentrates, can potentially be considered at high risk for OBI, especially since these patients usually are HIV or HCV co-infected. This study aimed to assess the prevalence of occult HBV infection in Greek patients with hereditary bleeding disorders. The study sample comprised of 114 patients from a single haemophilia center. All patients were screened for HBV serum markers and individually tested for HBV DNA using a qualitative PCR. Presence of HBV DNA was further confirmed by quantification of viral load with an ultrasensitive in-house real time PCR. 88 and 21 patients with haemophilia A and B, respectively, 4 patients with von Willebrand Disease and 1 patient with severe factor VII deficiency were screened for the presence of OBI. Anti-HBc were detected in 53 (46.5%) subjects; 18 of them were anti-HBs(-) and 35 anti-HBs(+). Anti-HBe were present in 26 subjects. Two out of 114 patients were HBsAg(+). Of the remaining 112 HBsAg(-) patients tested, two (1.8%) were found HBsAg(-), HBV DNA(+), anti-HBc(+) and anti-HBs(-) and were identified as potential OBI cases. Both cases exhibited very low DNA levels; 38.2IU/mL in patient A and 14.2IU/mL in patient B. Both patients were HBeAg(-), but patient A had HBe antibodies. Patient B was also HIV/HCV co-infected. In conclusion, two cases of OBI with low HBV viraemia were identified among patients with congenital bleeding disorders. Although the incidence in our sample is moderately low (1.8%), close monitoring of these infections is of great clinical significance, especially in patients with co-infections and concomitant immunosuppression.

Screening and evaluation of chronic and occult Hepatitis B in chemo - radiotherapy patients with cancer

BACKGROUND

Hepatitis B virus infection (HBV) and its complications is one of the most serious problems of the health system in many parts of the world. In the present study, we will assess chronic and occult HBV and isolated anti-Hepatitis B core antigen whose screening and evaluation is not routine in different populations.

MATERIALS AND METHODS

This descriptive analytical study was conducted on 213 patients undergoing chemotherapy - radiotherapy referred to the hematology - oncology clinics of Isfahan, Iran in 2012. In order to determine the serum levels of hepatitis B surface antigen (HbSAg), Hepatitis B Antigen and Antibody (HBCAb), aspartate aminotransferase (AST), alanine transaminase (ALT) and Alkaline phosphatase (ALK.P), venous blood samples were obtained. If the HBCAb sample was positive, another sample of the serum was sent to the laboratory to perform polymerase chain reaction and to determine viral load.

RESULTS

The mean age of the patients was 47.7 ± 9 years, with an age range of 27 -73 years; 98 (46%) and 115 (54%) cases were male and female, respectively, with mean age of 51.9 ± 8.3 and 44.1 ± 8.1 years, and there was no significant difference (P < 0.001). The mean level of liver enzymes including AST, ALT and ALK.P were 34.2 ± 36.02, 38.9 ± 47.1 and 252.1 ± 234.7, respectively. Two cases were HbSAg positive (0.9%) and six cases were HBCAb positive (2.8%) and HbSAg negative. Three cases had a high viral load at the rate of starting treatment among positive anti-HBC patients.

CONCLUSION

Because occult hepatitis is investigated less commonly in routine studies, it seems that screening and evaluating its prevalence is useful in the management of patients.

Molecular Characterization of Pre-Core/Core and S Region of Hepatitis B Virus in Hemodialysis Patients With Occult Hepatitis B Infection

BACKGROUND

Occult hepatitis B infection (OBI) is a major public health problem worldwide, which harbors potential risk of hepatitis B virus (HBV) transmission through blood transfusion and transplantation. OBI is characterized by the presence of HBV-DNA in the blood or liver tissue without detectable hepatitis B surface antigen (HBsAg) in the serum. An important cause of OBI is the occurrence of mutations in the HBV genome, especially in the S region.

OBJECTIVES

The study aims to analyze mutations in S and pre-core/core regions of HBV-DNA in hemodialysis patients.

PATIENTS AND METHODS

Sera of 216 hemodialysis patients were tested for HBsAg and hepatitis B core antibody (HBcAb) by ELISA. Sera of patients that tested negative for HBsAg were evaluated by PCR for the detection of HBV-DNA in the S and pre-core/core regions. In total, six PCR products were sequenced, aligned, and compared with the HBV reference sequence. Amino acid deletion and nucleotide substitution were considered mutations in S and pre-core/core regions of HBV-DNA.

RESULTS

Among 216 patients, 203 (93.98%) and 175 (81.01%) sera samples tested negative for HBsAg and HBcAb, respectively. Among all HBsAg-negative samples, six (2.9%) tested positive for HBV-DNA, including four (1.97%) for S and two (0.98%) for pre-core regions. All four (1.97%) samples that tested positive for the S region belonged to HBV-subtype awy. The amino acid sequence of all four samples showed the YMDD motif in position 204 (rtM204). There were three amino acid substitutions in the S region (T127P, P153L, and F170S) and one substitution in the RT region (Y135S). Moreover, two (0.98%) pre-core/core positive patients had an unexpected stop codon in position 1896.

CONCLUSIONS

This study indicates that 2.9% of hemodialysis patients had OBI, which is considered as a major public health problem worldwide. Moreover, we observed three mutations in S region, including T127P, P153L, and F170S, which caused OBI. This study is first to report a mutation analysis of HBV in hemodialysis patients in southwestern Iran. These results indicate that current screening tests based on HBsAg detection are not reliable for detection of HBV infection in dialysis patients.

The prevalence of hepatitis C virus infection and its related risk factors among the rural population of fars province, southern iran

BACKGROUND

Hepatitis C virus (HCV) infection is a major blood-borne infection with silent epidemic, major global public health problem and diverse prevalence worldwide.

OBJECTIVES

This study aimed to evaluate the prevalence of HCV infection and related risk factors in the general population of two villages, Farmashkan and Akbarabad, of the Kavar City in Fars Province, Iran.

PATIENTS AND METHODS

A 34-month cross-sectional study was performed on all people of the villages aged ≥ 7 years from July 2007 to April 2010. Demographic information and history of HCV-related risk factors were extracted from their medical records. For each participant, the serum anti-HCV IgG was assessed by the commercial enzyme-linked immunosorbent assay (ELISA) kits.

RESULTS

A total of 6095 participants (36.4% male and 65.6% female) with the mean age of 92 (7-95) and mean ± SD of 34.6 ± 17.3 years were included in this study. Fifteen persons (0.24%) were detected as HCV-positive and the highest prevalence was seen in age ≤ 12 years old (1%). A significant association was only detected between blood transfusion and HCV infection; therefore, those persons with history of blood transfusion had 15-fold higher risk for HCV seropositivity (odds ratio 15.54, 95% CI = 4.89-49.41).

CONCLUSIONS

Our reported rate of HCV seropositivity is similar to the previous Iranian reports. However, future evaluations should be focused on the Polymerase Chain Reaction method for the detection of HCV and determining and evaluating of other related risk factors. Moreover, more attention should be paid to blood donors as a reservoir population of HCV.

Important roles played by TGF-β in hepatitis B infection

Hepatitis B virus (HBV) which includes, fulminant, acute, chronic, asymptomatic, and occult HBV infection is the most prevalent virus that leads to human liver diseases. Chronic, asymptomatic, and occult infection can induce further sever diseases such as hepatocellular carcinoma (HCC) and cirrhosis of the liver. The underlying mechanisms that allow progression of the prolonged forms of the infection and subsequent HCC or cirrhosis of the liver are yet to be clarified. However, many researchers have suggested that immunological and genetic parameters may play important roles in the etiology of hepatitis B. Transforming growth factor beta (TGF-β) is an important cytokine with dual regulatory functions in the immune system and in the responses against viral infections. However, the pathways and mechanisms controlling these are not fully understood. The crucial roles of TGF-β in the development of Th17 and T regulatory lymphocytes, the main cell types involved in autoimmunity and destructive immune related diseases, have been documented and this provides insights into TGF-β function during hepatitis infection and subsequent HCC and cirrhosis of the liver. Recent findings also confirm that TGF-β directly alters hepatocyte function during hepatitis B, hence, the aim of this review is to address the current data regarding the association and status of TGF-β with hepatitis B infection and its related disorders including HCC and cirrhosis of the liver.

Health related quality of life in Iranian hemodialysis patients with viral hepatitis: changing epidemiology

BACKGROUND

There are surprisingly a few studies that evaluate the impact of chronic viral hepatitis, which is common in HD (hemodialysis) patients, on HRQOL (health related quality of life).

OBJECTIVES

We conducted a study to evaluate the impact of chronic viral hepatitis on HRQOL and to compare their HRQOL with non-infected HD patients via a HRQOL questionnaire.

PATIENTS AND METHODS

The Iranian adapted version of the Kidney Disease Quality of Life Short Form (KDQOL-SF) version 1.3 questionnaires were filled out by the HD patients. In all HD patients, serum HBsAg, HBS Abs, and HCV Abs [enzyme-linked immunosorbant assay (ELISA)] were routinely checked every six months. Patients were considered to have chronic HBV infection if HBsAg was positive for more than six months. In all HD patients, third generation assay was used to detect HCV infection. Furthermore, serum HCV-RNA (PCR) was examined in anti-HCV-positive patients for confirmation of HCV infection.

RESULTS

in this cross sectional study 4101 patients from 103 dialysis units in Iran between October 2010 and August 2011 were included. Prevalence of hepatitis B and hepatitis C infection was 2.1% and 1.3% respectively. Almost all KDQOL items for viral hepatitis patients had equivalent or better scores than those without viral hepatitis. In the logistic regression after adjustment for age, sex, educational level, marital status, dialysis vintage, HBs Ag positivity and HCV Ab positivity, only age (P < 0.001) and educational level (P = 0.015) had negative impact on quality of life.

CONCLUSIONS

Our data show that not only general health and physical activity were preserved but also health perception may be better among HD patients with viral hepatitis.

Epidemiological features of hepatitis B and C infection in a high risk population: results of screening programs

AIM

The aim of this study was to report the epidemiological features of HBV & HCV infection in an Iranian high risk population.

BACKGROUND

Hepatitis B and hepatitis C infections are worldwide serious public health problems. Iran has an intermediate prevalence of infection and a screening program was started in 2010 among high risk individuals.

PATIENTS AND METHODS

This cross-sectional study was conducted on 4455 new patients during two past years. Demographic information, age, gender, occupational status, medical history, history of vaccination against HBV, high risk exposure and laboratory findings were collected for each patient. Then distribution of demographic and risk factors was evaluated in each type of hepatitis.

RESULTS

The mean age of patients was 45.6±17.3 years. More than two-thirds of the diagnosed cases were infected with HBV. 74% of patients were carriers of hepatitis virus. 60% of patients had no symptoms at diagnosis. Illicit intravenous drug use was most common high risk exposure in patients under study (n=366, 8.2%). High risk behaviors including illicit intravenous drug use and unprotected sex were relatively higher in patients infected with hepatitis C compared to patients with hepatitis B infection.

CONCLUSION

Findings of this study suggest that illicit intravenous drug use, contact with an infected household member and unprotected sex are the most common high risk exposure in Iranian patients infected with viral hepatitis. Therefore, preventive strategies such as health education, vaccination and screening programs should be directed to these groups. The results also show that a majority of patients have no symptoms at the time of diagnosis, therefore periodic screening tests in high risk groups is required.