Anti-hepatitis B antibody levels In immunized medical students: are they at risk?

Abstract INTRODUCTION Medical students have an occupational risk for hepatitis B (HB). This study sought to determine anti-HBs and anti-HBc IgG levels in vaccinated students, check their seroconversion, and correlate this with vaccination. METHODS One hundred and forty-three students' blood samples and their vaccination schedules were analyzed. RESULTS: 65.7% were positive for anti-HBs; however, anti-HBs was absent in 34.3%. Only two samples were positive for anti-HBc IgG. CONCLUSIONS More than 30% of students did not have minimum protective levels. Comparing HBV vaccination and anti-HBs reactivity, the majority of reactive individuals received their last dose within the past 16 years.

Definition, Diagnosis, and Prevalence of Occult Hepatitis B Virus Infection / 대한소화기학회지

Occult HBV infection is characterized by the absence of serum HBsAg with persistence of low level of intrahepatic HBV DNA. Several suggested mechanisms for the origin of occult HBV infection include strong suppression of viral replication and gene expression, mutation in the regulatory regions of HBV genome, formation of immunoglobulin-bound HBsAg, viral interference, and blockage of HBsAg secretion from infected hepatocytes. Standardized assays are not yet available, and sensitive HBV DNA amplification assay is necessary for the diagnosis of cryptic infection. Detection rate of HBV DNA is highest in IgG anti-HBc positive population. However, neither anti-HBc nor anti-HBs can be detected in a significant proportion of infected persons. Occult HBV infection occurs in a number of clinical settings and is highly prevalent in HCV-infected patients as well as in patients with cryptogenic chronic liver disease including hepatocellular carcinoma.

Occult Hepatitis B Virus Infection: Transmission and Reactivation / 대한소화기학회지

Occult HBV infection (OBI) is defined as presence of HBV DNA in the liver tissue in patients with serologically undetectable HBsAg. There are differences in virologic and serological profiles of OBI. Majority of OBI are positive for anti-HBs and/or anti-HBc and minor portion are negative for all HBV markers. However, there are no HBV mutations in the surface and its regulatory regions. HBV infection persists by the presence of covalently closed circular DNA (cccDNA) within the infected hepatocytes, which serves as a reservoir for future infection. OBI increases the risk of HBV transmission through transfusion, hemodialysis, and organ transplantation. Therefore effective measures should be employed to screen OBI. Antiviral therapy is needed in HBsAg-negative transplant patients who are anti-HBc positive to prevent the recurrence of HBV infection. Since HBV replication is strongly suppressed by immune surveillance system in OBI patients, immunosuppression results in massive HBV replication. This leads to acute hepatitis and sometimes mortality when immune surveillance is recovered after stopping immunosuppressive drugs/anticancer chemotherapy. Therefore, narrow surveillance is required to recognize the viral reactivation and start antiviral agents during immunosuppressive therapy/anticancer chemotherapy in patients with OBI.

Prevalence of Occult Hepatitis B Virus Infection in Hemodialysis Patients / 대한소화기학회지

BACKGROUND/AIMS: The prevalence of occult HBV infection depends on the prevalence of HBV infection in the general population. Hemodialysis patients are at increased risk for HBV infection. The aim of this study was to determine the prevalence of occult HBV infection in hemodialysis patients. METHODS: Total of 98 patients undergoing hemodialysis in CHA Bundang Medical Center (Seongnam, Korea) were included. Liver function tests and analysis of HBsAg, anti-HBs, anti-HBc and anti-HCV were performed. HBV DNA testing was conducted by using two specific quantitative methods. RESULTS: HBsAg was detected in 4 of 98 patients (4.1%), and they were excluded. Among 94 patients with HBsAg negative and anti-HCV negative, one (1.1%) patient with the TaqMan PCR test and 3 (3.2%) patients with the COBAS Amplicor HBV test were positive for HBV DNA. One patient was positive in both methods. Two patients were positive for both anti-HBs and anti-HBc and one patient was negative for both anti-HBs and anti-HBc. CONCLUSIONS: The present study showed the prevalence of occult HBV infection in HBsAg negative and anti-HCV negative patients on hemodialysis at our center was 3.2%. Because there is possibility of HBV transmission in HBsAg negative patients on hemodialysis, more attention should be given to prevent HBV transmission.

A study of hepatitis B virus reactivation associated with rituximab therapy in real-world clinical practice: a single-center experience

BACKGROUND/AIMS: The widespread use of cytotoxic chemotherapy and immunosuppressants has resulted in reactivation of hepatitis B virus (HBV) recently becoming an issue. Although rituximab (an anti-CD20 monoclonal antibody) has revolutionized the treatment of lymphoma, recent reports have suggested that rituximab therapy increases the risk of viral-mediated complications, and particularly HBV reactivation. This study analyzed real clinical practice data for rituximab-related HBV reactivation. METHODS: Between January 2005 and December 2011, 169 patients received treatment with rituximab. Screening status of the HBV infection and frequency of preemptive therapy were determined in these patients, and the clinical features of HBV reactivation were analyzed. RESULTS: Seventy-nine of the 169 patients with chronic or past HBV infection were selected for evaluation of HBV reactivation. Of the 90 patients who were excluded, 22 (13.0%) were not assessed for HBsAg and anti-HBc, and 14 (8.3%) were not assessed for anti-HBc due to seronegativity for HBsAg. The selected patients were divided into those with chronic HBV infection (n=12) and those with past HBV infection (n=67); six patients (7.6%) experienced HBV reactivation. Eight patients received preemptive therapy, but three patients (37.5%) underwent HBV reactivation. Although HBsAg seropositivity was an independent risk factor for HBV reactivation (P=0.038), of the six patients with HBV reactivation, two (33.3%) had past HBV infection and three (50%) died of liver failure. CONCLUSIONS: The findings of this study demonstrate that adherence to guidelines for screening and preemptive therapy for HBV reactivation was negligent among the included cohort. Attention should be paid to HBV reactivation in patients with past as well as chronic HBV infection during and after rituximab therapy.

Antibody levels in children after 10 years of vaccination against hepatitis B: a brazilian community-based study / Níveis de anticorpos em crianças 10 anos após a vacinação contra hepatite B: um estudo brasileiro de base comunitária

INTRODUCTION: It is known that the hepatitis B (HB) vaccine is effective, but it is alarming that sudden drops of antibody levels may coincide with the onset of adolescence. METHODS: Antibody levels against HB vaccine surface antigen (anti-HBs) and HB vaccine core antigen (anti-HBc) were measured on the blood samples of children with a mean age of 11.4 years. RESULTS: About 54.8% had protective levels of anti-HBs. Of those who were anti-HBc-positive (4.4%), an average of 218.4 anti-HBs mIU/mL was found. CONCLUSIONS: Immunological protection was found in the majority of children. However, more studies are needed to elucidate the heritability of nonresponders and establish strategies against such events.

INTRODUÇÃO: Sabe-se que a vacina contra a hepatite B é eficaz, mas é preocupante que quedas bruscas nos níveis de anticorpos possam coincidir com o início da adolescência. MÉTODOS: Níveis de anticorpos anti-HBs e anti-HBc foram medidos nas amostras de sangue de crianças com idade média de 11,4 anos. RESULTADOS: Cerca de 54,8% apresentaram níveis protetores de anti-HBs. Dos que apresentaram anti-HBc positivo (4,4%), uma média de anti-HBs de 218,4mUI/mL foi encontrada. CONCLUSÕES: Proteção imunológica foi encontrada na maioria das crianças. No entanto, mais estudos são necessários para elucidar a herança de não-respondedores e estabelecer estratégias contra tais acontecimentos.

Significance of anti-HBc screening of blood donors & its association with occult hepatitis B virus infection: Implications for blood transfusion.

Background & objective: Expansions of blood donor screening and improved laboratory detection of viral markers have remarkably reduced the risk for infection with transfusion-transmitted viruses. This study was aimed to evaluate the presence of anti-HBc and to determine the presence or absence of HBV DNA in the serum samples from HBsAg negative, anti-HBc positive blood donors in a tertiary care hospital blood bank from Delhi. Methods: A total of 2175 HBsAg negative, first time volunteer blood donors were included in the study from blood bank, Lok Nayak Hospital, New Delhi. The blood specimens from all these subjects were evaluated for anti-HBV-core antigen (anti-HBc) serology, anti-HBV-surface antigen (anti-HBs) titres and HBeAg. The presence of HBV DNA was evaluated by testing, through polymerase chain reaction (PCR) techniques. Results: Of the 2175 HBsAg negative voluntary blood donors, 413 (19.8%) were tested to be positive for anti-HBc alone. Of these, 153 (group-I) were anti-HBs negative whereas group-II comprises a total of 260 anti-HBs positive cases i.e. 89 out of 413 had anti-HBs titres of 10-99 IU/l and the remaining 171 had anti-HBs titres of 100-500 IU/l. HBV DNA was detected in 7.5 per cent anti-HBc positive samples irrespective of anti-HBs status. Interpretation & conclusions: Our results showed that 18.9 per cent of our donor population was anti-HBc reactive, and hence inclusion of anti-HBc testing will lead to a high discard rate. The presence of HBV DNA in fairly high percentage of anti-HBc positive samples highlighted the need for a stringent and better screening system to prevent occult HBV infection.

An Experience of the Use of Anti-HBc and Anti-HBs for Blood Donor Screening Tests at a Tertiary Hospital Blood Center in Korea / 대한진단검사의학회지

BACKGROUND: The aim of this study was to report the first experience of using tests of antibody to hepatitis B core antigen (anti-HBc) and antibody to hepatitis B surface antigen (anti-HBs) for the selection of blood donors in a tertiary hospital blood center in Korea. METHODS: From January 2005 to December 2007, the data of all eligible donors according to the Korean Blood Regulation Law were analyzed. Anti-HBc testing was performed in all donors, but anti-HBs was tested only in anti-HBc seropositive donors. Anti-HBs negative but anti-HBc positive donors were regarded as ineligible for blood donation. Cost for donor testing was calculated based on Korean health insurance payment schedule from 2005 to 2007. RESULTS: The seroprevalence of anti-HBc in blood donors was 23.2% (162/699) and increased with increasing age. The proportion of ineligible donors for blood collection was 2.7% (19/699) of total donors and 11.6% (19/162) of anti-HBc seropositive donors. The cost of testing for anti-HBc and anti-HBs was estimated to be about 40% of the total screening cost. CONCLUSIONS: Although additional donor screening tests for anti-HBc and anti-HBs requires increased cost and relatively small number of donors are additionally excluded by these tests, they are considered to be helpful for the safety of blood products, because our blood center has characteristics with small number of donors and relatively high percentage of donors in the age group of thirties and older.

Hepatite crônica B oculta: prevalência e aspectos clínicos em população de elevada endemicidade de infecção pelo vírus da hepatite B na Amazônia Ocidental Brasileira / Occult hepatitis B: prevalence and clinical characteristics in a population with high endemicity of hepatitis B infection in the western Brazilian Amazon region

Recentemente é descrito estado de persistência do vírus da hepatite B denominado hepatite crônica B oculta. Sua prevalência e fisiopatologia são desconhecidas. O objetivo deste estudo foi avaliar a ocorrência dessa entidade clínica em pacientes da Amazônia brasileira. De 51 pacientes anti-HBc total reativos testados pela reação em cadeia da polimerase, 17 por cento foram positivos. Não observamos associação com fatores de risco clássicos de infecção pelo vírus da hepatite B, testes bioquímicos, hematológicos e histopatologia. No entanto, os pacientes ictéricos e reativos para o anti-HIV apresentaram associação com a presença do ADN-vírus da hepatite B. Os resultados demonstram a ocorrência da hepatite crônica B oculta, entre nossos doentes, porém, com taxas de prevalência abaixo do esperado para a região. Acreditamos que, apesar do tamanho da amostra avaliada ser pequeno, sua ocorrência poderia ter sido maior se empregássemos primers para a região S, C e X do genoma do vírus da hepatite B, aumentando a sensibilidade do teste.

A persistent form of the hepatitis B virus called occult chronic hepatitis B has recently been described. Its prevalence and physiopathology are unknown. The aim of this study was to evaluate the occurrence of this clinical entity among patients in the Brazilian Amazon region. Out of 51 anti-HBc total-positive patients who were tested using the polymerase chain reaction, 17 percent were positive. We did not find any associations with classical risk factors for hepatitis B virus infection or with biochemical tests, hematological tests or histological patterns. However, the jaundiced and HIV-positive patients showed a statistical association with the presence of hepatitis B virus-DNA. The results demonstrated that occult hepatitis B occurred among our patients, but at prevalence rates lower than expected for this region. We believe that despite the small sample size, the occurrence might have been found to be greater if we had used primers for the S, C and X regions of the hepatitis B virus genome, thereby increasing the sensitivity of the test.

The significance of anti-HBc and occult hepatitis B virus infection in the occurrence of hepatocellular carcinoma in patients with HBsAg and anti-HCV negative alcoholic cirrhosis / 대한간학회지

BACKGROUND/AIMS: Alcohol and the hepatitis B virus (HBV) exert synergistic effects in hepatocelluar carcinogenesis. We aimed to elucidate the clinical significance of the antibody to hepatitis B core antigen (anti-HBc) and occult HBV infection on the development of hepatocellular carcinoma (HCC) in patients with alcoholic liver cirrhosis (LC). METHODS: Patients with alcoholic LC alone (n=193) or combined with HCC (n=36), who did not have HBsAg or antibody to hepatitis C virus were enrolled. Clinical data and laboratory data including anti-HBc were investigated at enrollment. The polymerase chain reaction was applied to HBV DNA using sera of patients with HCC or LC after age and sex matching. RESULTS: Patients with HCC were older (60+/-11 years vs. 53+/-10 years, mean+/-SD, P<0.001), more likely to be male (100% vs. 89%, P=0.03), and had a higher positive rate of anti-HBc (91.2% vs. 77.3%, P=0.067), and a higher alcohol intake (739+/-448 kg vs. 603+/-409 kg, P=0.076) than those with LC. Age was the only significant risk factor for HCC revealed by multiple logistic regression analysis (odds ratio, 1.056; P=0.003). The positive rate of anti-HBc and alcohol intake did not differ in age- and sex-matched subjects between the LC (n=32) and HCC (n=31) groups. However, the detection rate of serum HBV DNA was higher in the HCC group (48.4%) than in the LC group (0%, P<0.001). CONCLUSIONS: Anti-HBc positivity is not a risk factor for HCC. However, occult HBV infection may be a risk factor for HCC in patients with alcoholic LC.

Isolated antibody to hepatitis B core antigen in HIV-1 infected patients and a pilot study of vaccination to determine the anamnestic response.

BACKGROUND: Isolated antibody to hepatitis B core antigen (anti-HBc) is frequently found in HIV-infected patients. The present study aimed to determine the prevalence and risk factors of isolated anti-HBc and the anamnestic response to hepatitis B vaccination in this population. MATERIAL AND METHOD: HIV-infected patients who visited Ramathibodi Hospital in May 2006 were included to test hepatitis B serology. Subjects with isolated anti-HBc were given hepatitis B vaccine and tested for anti-HBs. RESULTS: Of 140 patients, 28 (20%) had isolated anti-HBc. From multivariate analysis, IVDU (OR 30.8, p < 0.001) and anti-HCV seropositive (OR 6.7, p = 0.002) were independent risk factors for isolated anti-HBc. Two from 28 (7%) patients who received vaccine had a response to vaccination. CONCLUSION: Prevalence of isolated anti-HBc among Thai HIV-infected patients was 20%. Risk factors of isolated anti-HBc were IVDU and anti-HCV seropositive. Anamnestic response to hepatitis B vaccination was low. Further study with strategies to improve the response of vaccination is needed.

Seropositivity for hepatitis B virus, vaccination coverage, and vaccine response in dentists from Campo Grande, Mato Grosso do Sul, Brazil

This study investigated the seropositivity for hepatitis B virus (HBV), the vaccination index, and the vaccine response index in dentists from Campo Grande, MS. Blood samples from 474 dentists (63.7 percent women and 36.3 percent men), with a mean age of 38.5 ± 10.5 years were analyzed by enzyme-linked immunosorbent assay to detect the serological markers: HBsAg, anti-HBs, and anti-HBc. The HBsAg positive samples were tested for anti-HBc IgM, HBeAg, and anti-HBe. A total of 51 (10.8 percent) dentists showed seropositivity for HBV. Three (0.6 percent) were HBsAg/anti-HBc/anti-HBe positive, 43 (9.1 percent) were anti-HBc/anti-HBs positive, and 5 (1.1 percent) had only anti-HBc. Viral DNA was detected by polymerase chain reaction in 9 (17.6 percent) out of 51 HBV seropositive samples. A vaccination index of 96.6 percent (458/474) was observed, although 73.1 percent (335/458)completed the three-dose schedule. Excluding 46 HBV seropositive individuals from 458 that reported vaccination, 412 were analyzed for vaccine response index. It was observed that 74.5 percent (307/412) were anti-HBs positive; this percentage increased to 79.1 percent when three doses were administered. The results showed a high vaccination index and a good rate of vaccine response; however, the failure in completing the three-dose schedule and the occurrence of HBV infection reinforce the need for more effective prevention strategies.

Avaliacão da pré-triagem sorológica para o marcador do vírus da hepatite B (anti-HBc total) em candidatos à doacão de sangue no Estado do Acre, 2002 / Evaluation of the sorologic pre-selection for the hepatitis B virus marker (total anti-HBc) in candidates to blood donation in the state of Acre, 2002

O objetivo da pesquisa foi avaliar a pré-triagem sorológica para hepatite B (anti-HBc total) em candidatos à doacão de sangue, verificando a associacão entre as variáveis sexo, faixa etária, escolaridade e naturalidade. Estudo transversal com dados retrospectivos, tendo como populacão-alvo candidatos à doacão de sangue naturais dos municípios do interior do Acre, que procuraram o Centro de Hematologia e Hemoterapia do Acre, no período de janeiro a dezembro de 2002. Dos 673 candidatos incluídos foi constatado reatividade ao anti-HBc total em 54,8 por cento. Sendo observado maior reatividade ao anti-HBc total entre os candidatos do sexo masculino, faixa etária mais avancada e menor grau de escolaridade (p<0,05). A pré-triagem sorológica para hepatite B em candidatos a doacão de sangue é uma alternativa viável, visto que, reduz o custo e aumenta a seguranca transfusional. A captacão de doadores do sexo feminino, jovens e com grau de escolaridade acima do fundamental sinaliza potenciais doadores de sangue para o HEMOACRE.

Change of Hepatitis B Virus DNA Status in Anti-HBc Positive Liver Graft / 대한간학회지

BACKGROUND/AIMS: Many patients with positive anti-HBc, but negative HBsAg, are known to harbor occult HBV infection, which may transmit the virus through the graft in liver transplantation. We examined the change of HBV DNA within the liver allograft tissue of the donor with positive anti-HBc, but negative HBsAg, before and after the transplantation and assessed its significance. METHODS: Twenty-eight patients with available posttransplant biopsies that received anti-HBc positive liver allografts between April 2000 and November 2003 were enrolled in the study. Intraoperative wedge biopsy of donor liver and needle biopsy of the recipient around the 12th postoperative day were used. HBV DNA within the liver tissue was identified by polymerase chain reaction technique using paraffin-embedded liver tissue. RESULTS: Among 13 patients that showed positive amplification before transplantation, 10 turned negative and 3 remained positive after transplantation. One patient, who was negative, became positive after transplantation. Three patients had recurrent HBV infection, but none had positive PCR before or after transplantation and recurrence was not associated with PCR results. Donors with low anti-HBs titer were more likely to be PCR positive compared to donors with high anti-HBs serology (P<0.05). CONCLUSIONS: Under adequate prophylactic measures, the presence of HBV DNA within the liver tissue does not affect recurrence and most allografts harboring HBV DNA before transplantation will eventually show viral clearance. However, many anti-HBc positive allografts are infected by HBV at subclinical level so vigilant surveillance is essential.

Significance of isolated hepatitis B core antibody in blood donors from Säo Paulo

The clinical significance of isolated anti-HBc is still a challenge. To elucidate the real importance of this finding in our blood donors, an investigation algorithm was tested. One hundred and twelve isolated anti-HBc seropositive blood donors underwent clinical evaluation and retesting of HBV markers. Those who presented repeatedly reactive isolated anti-HBc, received a single dose of hepatitis B recombinant vaccine to verify anti-HBs early response. A HBV-DNA determination by PCR was done for those who did not test positive to anti-HBs after vaccine. The level of anti-HBc was recorded as a ratio of the sample-to-cut-off values (S:C ratio) in 57 candidates at donation. Comparing true and false-positive anti-HBc results, the different S:C ratios of them were statistically significant and when less than 2, implying in a false-positive result probability over 80 percent. A high percent of false-positive results (16.07 percent) was verified after anti-HBc retesting. HBV immunity was characterized in 49.11 percent, either by anti-HBs detection in retesting (15.18 percent), or after a single dose HBV vaccination (33.93 percent). HBV-DNA was negative in all tested donors. In conclusion, this algorithm was useful to clarify the meaning of isolated anti-HBc in most of our blood donors

Prevalence of antibodies to hepatitis B core antigen in blood donors in the Middle West region of Brazil

The prevalence of antibodies to hepatitis B core antigen in 552 prime blood donors was of 9.4 percent. The majority (71.2 percent) has antibodies to hepatitis B surface antigen. The hepatitis B surface antigen was present in 0.7 percent, all of them antibodies to hepatitis B core antigen positive

Response to hepatitis B vaccination in high risk population.

Hepatitis B vaccine is well established as very efficacious, but immune response to the vaccine is highly individual specific. A study involving fifty vaccinees was undertaken at the Hepatitis Laboratory, National Institute of Communicable Disease, Delhi. One ml (20 microgram) of Engerix B vaccine (recombinant yeast derived vaccine) was administered in the standard three dose schedule (0, 1 and 6 months). The sero-conversion of the vaccinees was 24%, 66%, 76% and 78% at 1 month, 6 months, 7 months, and 12 months respectively. There was no seroconversion in 22% of the vaccinees. Sero-conversion was assessed using Macro ELISA test (Ausab, Abbott Labs) for Anti HBs reactivity.