Significance of isolated anti-HBc seropositivity by ELISA: implications and the role of radioimmunoassay.

Hepatitis B virus (HBV) surface antigen (HBsAg) and antibody to HBsAg (anti-HBs) are excellent markers for HBV infection and its immunity. The significance of isolated antibody to HBV core antigen (anti-HBc) seropositivity is not certain. To elucidate this, sera from 638 Chinese adult subjects, aged 18-52 years, seronegative for both HBsAg and anti-HBs, were tested for anti-HBc. Fifty-one (8%) were found to have an isolated anti-HBc seropositivity by ELISA, and all were negative for IgM-anti-HBc. The anti-HBc persisted in all subjects who attended follow-up for hepatitis B vaccination (n = 48) for a period of 8 months. These 48 subjects received 3 doses of hepatitis B vaccine (HB-VAX, 10 micrograms or 20 micrograms) at 0, 1, and 6 months: 72.9% developed a primary anti-HBs response (suggestive of a false-positive anti-HBc seropositivity), 4.2% developed an anamnestic or secondary anti-HBs response, and 22.9% did not develop an anti-HBs response. Increasing the cutoff point of the ELISA or reconfirmation with radioimmunoassay (RIA) reduced only a minor half of the false positives. This low specificity of anti-HBc ELISA/RIA, together with the high rate of anti-HBs response to hepatitis B vaccine, indicates that subjects with isolated anti-HBc seropositivity should be included in vaccination programs.     

HBV and HCV infection in Japanese dental care workers

Protective measures against occupational exposure to the hepatitis B virus (HBV) and hepatitis C virus (HCV) must be taken in order to prevent infection in dental care workers. To determine the best way to protect these workers, our study examined viral hepatitis infection in dental care workers in regions with a high prevalence of HCV infections in Japan. In total, 141 dental care workers (including dentists, dental hygienists and dental assistants) were enrolled. After a questionnaire to elicit demographic information was administered by an oral surgeon, hepatitis B surface antigen (HBsAg), antibody to HBs (anti-HBs), antibody to hepatitis B core antigen (anti-HBc) and antibody to HCV (anti-HCV) were measured. When necessary, HBeAg, anti-HBe, levels of HBV DNA, anti-HBc IgM and HCV RNA in serum were measured. Of the dental care workers included, 68 (48.2%) had been immunized with a HBV vaccine. Only 9 wore a new pair of gloves for each new patient being treated, 36 changed to a new pair only after the old gloves were torn and 24 did not wear any gloves at all. No one was positive for HBsAg or anti-HCV, though 73 (51.8%) and 17 (12.1%) workers were respectively positive for anti-HBs and anti-HBc. The positive rate of anti-HBc varied directly with worker age and experience. Of the 68 workers immunized with HBV vaccine, 51 (75%) were positive for anti-HBs. Of the 63 workers who were not so immunized, 17 (27%) were positive for anti-HBs and 15 of these were also positive for anti-HBc. Immunized workers were more protected against HBV infection than non-immunized workers, indicating that HBV vaccine was a useful measure for protection against the infection. The anti-HBc positive rate was significantly higher among dental care workers than general blood donors, suggesting that frequency of exposure to HBV was greater in dental care workers. HBV vaccination should be made compulsory for all dental care workers who handle sharp instruments.     

Diagnostic value of anti-HBc IgM in high HBV prevalence areas

The diagnostic value of an anti-mu-capture immunoassay for the detection of IgM antibody against hepatitis B core antigen (anti-HBc) was evaluated. Strongly positive results were obtained from the acute phase sera of the 25 acute hepatitis B patients who were hepatitis B surface antigen (HBsAg) positive and of the 18 confirmed acute hepatitis B patients who had already cleared HBsAg when symptoms developed. Negative results were obtained in 5 hepatitis A patients, 20 non-A, non-B acute hepatitis patients serologically susceptible to HBV, 22 patients with chronic hepatitis B liver disease, 15 asymptomatic HBsAg carriers, and 10 healthy patients immune from past HBV infection. Fourteen of the acute hepatitis patients remained HBsAg positive for a follow-up period of at least 6 months, and 12 of these were found consistently anti-HBc IgM negative. These were considered as chronic HBsAg carriers with a superimposed form of acute liver injury. These data show that this assay can differentiate between acute from chronic (HBsAg positive) and recent from old (HBsAg negative) hepatitis B virus infection. Thus, it should be very useful in the complex diagnostic situations encountered commonly in areas with high prevalence of HBV infections.     

Seroepidemiological studies on hepatitis B and D viruses infection among five ethnic groups in southern Taiwan

In order to compare the prevalence of hepatitis B virus (HBV) and hepatitis D virus (HDV) infection among five ethnic groups in Pingtung County of southern Taiwan, a total of 240 serum samples were collected from September to October, 1985, from the following five ethnic groups: Taiwanese, Hakka, Mainland Chinese, aboriginal Paiwanese, and aboriginal Rukaiese. Ages of subjects ranged from 5 to 69 years. All sera were tested for hepatitis B surface antigen (HBsAg), surface antibody (anti-HBs), and core antibody (anti-HBc) by radioimmunoassay (RIA). Hepatitis B e antigen (HBeAg) and antibody to hepatitis D antigen (anti-HDV) were also tested for those with HBsAg-positive sera. Results showed that 44.1% of all sera examined were negative for HBsAG but positive for both anti-HBs and anti-HBc; additionally, 24.6% were negative for both HBsAg and anti-HBs but positive for anti-HBc. Only 134 serum samples showed negative results for HBV markers, indicating an HBV infection rate of 88.8%. The anti-HDV positive rate was estimated to be 2.7% among HBsAg-positive subjects. The HBsAg-positive rates among Rukaiese, Paiwanese, Hakka, Taiwanese, and Mainland Chinese were 25.8, 22.5, 16.7, 12.9, and 10.0%, respectively; while the prevalence rates of HBV infection among the above five groups were 94.2, 94.6, 85.4, 87.5, and 82.5%, respectively. Differences in the HBsAg-positive rate and HBV infection rate among these ethnic groups were statistically significant. We conclude that people living in Pingtung County are more frequently infected with HBV when compared with inhabitants in northern Taiwan.     

Acute hepatitis B viral infection in a patient with anti-HBs.

We report a patient with antibody to hepatitis B surface antigen (anti-HBs) but no antibodies to other hepatitis B virus components, who developed acute symptomatic type B hepatitis. The possible explanations for this unusual serological pattern are 1) the antibody-positive status, which developed against only a subdeterminant of hepatitis B surface antigen (HBsAg), arose naturally or as the result of cross-reaction with a variety of antigens; and 2) seroconversion to anti-HBs occurred in response to surface antigen of a mutant strain of hepatitis B virus (HBV). This anti-HBs positivity, in the absence of antibody to hepatitis B core antigen, does not provide natural immunization against HBV infection, and so is not protective. Individuals who are positive to anti-HBs antibody alone which is not elicited by HBV vaccine, should be vaccinated against possible HBV infection.     

基因重组干扰素治疗急性乙型肝炎疗效观察

目的　以基因重组干扰素治疗急性乙型肝炎病人,观察其减少急性乙肝转慢率的效果。方法　用基因重组α干扰素（３００ 万Ｕ,肌内注射,隔日１ 次,１２ 周为一个疗程） 治疗１９ 名急性乙肝病人,对治疗后未产生抗ＨＢｓ 者,加用乙肝疫苗（３０ μｇ,肌内注射,每周注射１ 次,连用３ 周）;对照组为病情相似的１５ 例病人,服用一般保肝药物。结果　治疗组１８ 例（９５－０％ ,１８１９）ＨＢｓＡｇ 阴转,但均未产生抗ＨＢｓ,再用乙肝疫苗后,１７ 例（９４－０％ ,１７１９） 产生抗ＨＢｓ。２４～２４０ 周随访期间,１８ 例ＨＢｓＡｇ 阴转者无复发;１ 例ＨＢｓＡｇ 未阴转者,至随访结束时仍为阳性。对照组８ 例（５３－０ ％ ,８１５）ＨＢｓＡｇ 阴转,同时,８７－５ ％（７８）的病例产生抗ＨＢｓ,另７ 例ＨＢｓＡｇ 未阴转者,在２４ ～２４０ 周的随访期间,仅１ 例ＨＢｓＡｇ阴转,余６ 例ＨＢｓＡｇ 持续阳性。结论　对于急性乙型肝炎发病８ 周后ＨＢｓＡｇ 仍未阴转者,采用干扰素合用乙肝疫苗,对防止转慢及ＨＢｓＡｇ 阴转后抗ＨＢｓ 的产生可能有一定作用     

Occult hepatitis B virus infection in patients with leprosy

Leprosy patients may present with immune system impairment and have a higher hepatitis B virus (HBV) seroprevalence, justifying the investigation of occult HBV infection in these individuals. The aim of this study was to verify the frequency and the clinical factors associated with occult HBV infection in leprosy patients. Between 2015 and 2016, leprosy patients from a reference center in Brazil were interviewed to assess clinical data. Blood samples were collected for the screening of HBV serological markers using enzyme-linked immunosorbent assay. Patients with negative hepatitis B surface antigen (HBsAg) that had positive anti-HBc and/or anti-HBs were selected for HBV DNA detection using real-time polymerase chain reaction. SPSS was used for data analysis. Among 114 selected patients, six were identified with occult infection (5.3%) and five of them with multibacillary leprosy. Three patients with occult infection had a history of a type 2 reaction (P = 0.072; OR, 4.97; 95% CI, 0.87-28.52). Only two patients with occult infection had isolated anti-HBc, while three had isolated anti-HBs, including those with the highest HBV DNA titers. In conclusion, in leprosy patients with negative HBsAg and positive anti-HBc and/or anti-HBs, occult HBV infection occurs in 5.3% and can be found even in patients with isolated anti-HBs.     

Do CCR5 (CCR5Δ32) and TLR3 (RS5743313) gene polymorphisms prevent chronic hepatitis B infection?

Hepatitis B virus (HBV) is still a significant health problem in human. HBV severity or sensitivity of patients may be based on the individual genetic factors significantly. The aim of this study is to investigate the association of CCR5 (CCR5Δ32), TLR3 (rs5743313) functional gene polymorphisms, interferon-gamma (IFN-ɣ) level in HBV infection, which are thought to play an important role in innate and acquired immunity in patients who have undergone HBV seroconversion and those who have chronic hepatitis B disease and receive treatment. One hundred patients who are became naturally immune against HBV infection (HBsAg negative, anti-HBc IgG, and anti-HBs IgG positive), and 100 patients with chronic hepatitis B infection (>6 months HBsAg positive) who are receiving oral antiviral therapy were compared for CCR5Δ32, TLR3 (rs5743313) genotypes and serum IFN-ɣ level. It was found that CCR5Δ32 polymorphism (Wt/Δ32 and Δ32/Δ32) was significantly higher in the chronic hepatitis B group (p = 0.048) but not for TLR3 gene polymorphism. However, serum IFN-ɣ level was significantly higher in the HBV seroconversion group (75 ± 89 ng/ml) than in the chronic hepatitis B group (4.35 ± 17.27 ng/ml) (p < 0.001). In conclusion, a higher CCR5Δ32 allele frequency in patients with chronic hepatitis B might be considered as a marker of progression to chronic hepatitis.     

Chronic liver disease in transfusion-dependent thalassaemia: hepatitis B virus marker studies.

The systematic screening of 253 children with transfusion-dependent homozygous beta-thalassaemia revealed a high incidence of hepatitis B virus markers. The highest frequencies of hepatitis B surface antigen (HBsAg) and antibody to hepatitis B core antigen (anti-HBc) were found in the group of patients with the smallest number of transfusions, while the highest frequency of antibody to hepatitis B surface antigen (anti-HBs) was detected in the patients who had had the largest number of transfusions. Follow-up of these patients showed (a) a high incidence of acute hepatitis B, which was mainly subclinical; (b) normal hepatitis B surface antigen clearance and normal antibody to hepatitis B surface development; and (c) a high frequency of increased transaminase values for over six months. In all the subjects with persistently high transaminase, histological examination revealed chronic persistent hepatitis or chronic active hepatitis. Apart from two cases of chronic active hepatitis with no B virus markers, and two cases of chronic persistent hepatitis with HBsAg and anti-HBc in the serum, all these subjects were anti-HBs positive but HGsAg and anti-HBc negative.     

Seroepidemiology of hepatitis A, B, and D viruses and human T-lymphocyte tropic viruses in Japanese drug abusers

To evaluate the prevalence of hepatitis virus markers and human T-cell lymphotropic virus infections among drug abusers in Japan, serum samples were collected from 91 male drug abusers at the Shinshu University Hospital and the rehabilitation facility in Matsumoto and from 519 healthy male blood donors as controls. Sera were tested for antibody to hepatitis A virus (anti-HAV), hepatitis B surface antigen (HBsAg), antibody to HBsAg (anti-HBs), antibody to hepatitis B core antigen (anti-HBc), immunoglobulin M anti-HBc (IgM anti-HBc), antibody to hepatitis D virus (anti-HDV), antibody to HTLV type 1 (anti-HTLV 1), and antibody to human immunodeficiency virus (anti-HIV). The prevalence of anti-HAV was 13.2% in drug abusers and 10.8% in controls (not significant). The prevalences of HBsAg, anti-HBs, anti-HBc and exposure rate to hepatitis B virus (HBV) were 4.4%, 24.2%, 31.9%, and 35.2%, respectively, in drug abusers and 0.8%, 6.7%, 9.6%, and 9.6% in controls. The exposure rate to HBV was significantly different (P less than 0.001). IgM anti-HBc and anti-HDV were not detected in any sera. Anti-HTLV I was detected in three drug abusers (3.3%) and in one (0.2%) of the controls (P less than 0.01). All sera were negative for anti-HIV in all subjects. Infection with HBV and HTLV I is more common among drug abusers than in the general population of blood donors in Japan.     

Occult hepatitis B virus infection in Korean patients with isolated anti-HBc

Serological detection of isolated anti-hepatitis B core antibody (anti-HBc) can occur in various scenarios, but the most clinically relevant situation is occult hepatitis B virus (HBV) infection (OBI). The purpose of this study was to evaluate the prevalence and clinical relevance of isolated anti-HBc and of OBI with isolated anti-HBc from an unselected hospital population. A total of 14,253 patients referred for hepatitis B surface antigen (HBsAg)/anti-HBs testing were classified into either the Health Promotion Center (HPC) group or the patient group. For patients who were negative for both HBsAg and anti-HBs, an anti-HBc test was additionally performed. An HBV DNA real-time PCR test was performed on isolated anti-HBc patients, and their demographic and clinical data were reviewed. The measured prevalence of isolated anti-HBc and OBI in isolated anti-HBc patients was 5.9 % and 4.7 %, respectively. Prevalence was higher in males, elderly people, and the patient group than in females, the younger, and the HPC group, respectively. In most cases, the levels of HBV DNA load were very low (less than 200 IU/mL), and most cases of OBI presented without liver disease or history of HBV infection. The prevalence of isolated anti-HBc and OBI are affected by the methods of detection, subject population, and constituent factors such as sex and age. Although detection of HBV DNA does not always indicate infectivity, highly sensitive standardized HBV DNA tests are needed in clinical settings to exclude the possibility of OBI, especially in the advanced age group.     

Detection and significance of anti-HBc in the blood bank; preliminary results of a controlled prospective study

It has been suggested that post-transfusion hepatitis B (PTHB) may occur after transfusion with blood negative for hepatitis B surface antigen (HBsAg) but positive for antibody against hepatitis B core antigen (anti-HBc). We are currently conducting a controlled prospective study of recipients of such blood to investigate this possibility.Blood donors were routinely screened for HBsAg by radioimmunoassay (RIA) and those found negative were tested for anti-HBc by RIA. The HBsAg negative, anti-HBc positive donors were then tested for antibody directed against HBsAg by RIA, antibody directed against hepatitis B ‘e’ antigen by enzyme-immunoassay and for the liver enzymes SGOT and SGPT.Todate, follow-up has been completed in the recipients of 141 anti-HBc positive blood donors and in a control group of the recipients of 141 anti-HBc negative blood donors. All the recipients were bled repeatedly with intervals of 4–5 weeks up to 7 months post-transfusion. Currently, no clear-cut sero con version was observed in recipients of either group for any of the antibody markers of HBV infection. While none of the 141 recipients of anti-HBc negative blood became positive for HBsAg, recipients of anti-HBc positive blood acquired HBsAg and developed clinically manifest post-transfusion hepatitis B.     

Correlation between HBV DNA detection by polymerase chain reaction and Pre-S1 antigenemia in symptomatic and asymptomatic hepatitis B virus infections

The presence of hepatitis B virus (HBV) genome in sera from 73 symptomatic and asymptomatic HBsAg carriers was studied by the polymerase chain reaction (PCR) with primers specific for the S and C regions. Pre-S proteins of the HBV envelope were detected in serum by a specific monoclonal antibody in a double immunoradiometric assay. Out of twenty-five symptomatic patients with chronic active hepatitis (14 with HBeAg and 11 with anti-HBe), all were positive for HBV DNA by PCR, while 14/14 HBeAg and 2/11 (18%) of the anti-HBe patients were positive by dot blot hybridization. All but one anti-HBe patient (96%) carried Pre-S1 proteins. Among the asymptomatic HBsAg carriers, HBV DNA was detected by PCR in 14/14 (100%) HBeAg positive patients and in 25/34 (73%) anti-HBe positive patients. Pre-S1 proteins were found, respectively, in 14/14 (100%) and 11/22 (50%) of the same cases tested in parallel. The 20 healthy blood donors devoid of HBV markers and with normal transaminases tested were found negative for HBV DNA using PCR. Out of 12 patients who recovered from acute hepatitis B, all were found negative by PCR analysis after a mean follow up of 1 year after seroconversion to anti-HBs. When serial samples from 2 patients (one with acute hepatitis B, the other with chronic hepatitis B) were tested for the presence of HBV DNA and of Pre-S1 proteins, both markers showed parallel development.(ABSTRACT TRUNCATED AT 250 WORDS)     

乙肝核心抗体阳性供肝在肝移植中的应用

背景：现已经证实使用anti-HBc(+)供肝会使移植后乙肝复发的风险,但anti-HBc(+)供肝的应用明显缓解了供肝的相对匮乏。 目的：分析应用anti-HBc(+)供肝移植后乙肝复发风险及有效的预防措施。 方法：应用计算机检PubMed数据库中1994-01/2009-12关于anti-HBc(+)供肝文章,在标题和摘要中以“Hepatitis B core antibody; donor;liver transplantation”为检索词进行检索。选择与anti-HBc供肝相关文章。初检得到109篇文献,根据纳入标准选择48篇文章进行综述。 结果与结论：HBsAg(+)患者接受anti-HBc(+)供肝移植术后乙肝复发率为11%,生存率为67%~100%,与HBsAg(+)受者接受anti-HBc(-)供肝相似。HBsAg(-)受者接受anti-HBc(+)供肝总体感染率为19%,其中未感染过乙肝受者移植术后乙肝感染率为48%,感染过乙肝受者后感染率为15%。未感染乙肝与感染过乙肝受者移植后采取有效预防措施后感染率分别为3%,12%。采用HBIG、拉米夫定、联合用药的移植后感染率分别为19%,2.6%,2.8%。提示,采用anti-HBc(+)供肝做为供体是安全的,尤其是用在HBsAg(+)、anti-HBc(+)、anti-HBs(+)受者。而HBsAg(-)受者移植后接受拉米夫定可以有效复发乙肝感染。     

Diagnostic significance of anti-HBcIgM prevalence related to symptoms in Canadian patients acutely or chronically infected with hepatitis B virus

A total of 362 sera from 295 Canadian patients were examined for HBsAg, anti-HBs, anti-HBc, anti-HBcIgM, HBeAg, and anti-HBe using commercial immunoassays. Serial samples from 70 acutely infected patients demonstrated that anti-HBcIgM may detect 10% more positives than HBsAg within 4 months after the onset of clinical symptoms, and all except two were negative for anti-HBcIgM after the fourth month. None of 66 asymptomatic (HBeAg rate 18.2%) and two of 14 (14.3%) symptomatic (HBeAg rate 64.3%) carriers of HBsAg were positive for anti-HBcIgM (P = 0.029). Elevated marker responses were measured in two symptomatic carriers for a 20-month period. Anti-HBcIgM was not detected in either 100 asymptomatic patients positive for total anti-HBc, negative for HBsAg and negative for or possessing low levels of anti-HBs, 25 patients with liver disorders not caused by HBV, or 20 healthy milk donors. In diagnostic laboratory practice this anti-HBcIgM test may be useful in the following situations: to supplement HBsAg testing, providing a theoretical 10% increase in positives within 4 months following onset of acute viral hepatitis; to replace testing for anti-HBc and anti-HBs in symptomatic HBsAg-negative patients; to confirm whether a patient is experiencing acute or chronic HBV infection or symptoms superimposed upon asymptomatic HBsAg carriage by another cause, such as nonA-nonB viral hepatitis.     

Hepatitis B virus DNA in unusual serological profiles of hepatitis B surface antigen-positive sera

On the basis of a seroepidemiological survey of hepatitis B virus (HBV) infection conducted on 6208 random serum samples from four provinces of Thailand, we found 19 of 246 (7.7%) hepatitis B surface antigen (HBsAg)-positive samples with unusual serological constellations of HBV infection. Ten samples tested positive for HBsAg, anti-HBc (anti-hepatitis B core antibody), and anti-HBs (anti-hepatitis B surface antibody) markers (group I), 3 specimens were HBsAg and anti-HBs positive without detectable anti-HBc (group II), and the remaining 6 specimens showed only HBsAg (group III). In group I, 7 of 10 HBsAg-positive sera could be confirmed by HBsAg neutralization, yielding positive results for all samples. None of the group II sera were available in sufficient amounts for confirmation. In group III, five of six sera were confirmed by HBsAg neutralization, with four showing a positive reaction. HBV DNA was detected in 7 of 10 (70%) specimens in group I, in 1 of 3 (33.3%) specimens in group II, and in 3 of 6 (50%) specimens in group III. On the basis of HBsAg neutralization, HBV DNA was found in five of seven (71.4%) HBsAg-positive samples in group I and in three of four (75%) HBsAg-positive samples in group III, whereas the one confirmed HBsAg-negative sample in group III also remained negative for HBV DNA. Amino acid sequences were compared with those specifying the "a" determinant of the wild-type virus, particularly focusing on HBV-S protein variations between positions 110 and 160. Among 11 HBV DNA-positive sera, G145A was detected in 2 samples in group I, with the remaining samples identical to the wild-type virus. These unusual serological profiles may be due to the altered immune response of the host or to HBV variants.     

Low-dose vaccination against hepatitis B in children: one-year follow-up

Six hundred forty-three children, negative for markers of hepatitis B virus (HBV) infections, were given three X 2-micrograms doses of Merck, Sharp and Dohme (MSD) plasma derived hepatitis B vaccine (H-B-Vax) at monthly intervals. Twelve months after the first dose of vaccine, antibody to hepatitis B surface antigen (anti-HBs) was detected in 89% of children by radioimmunoassay (RIA) and in 83% by enzyme immunoassay (EIA). Seroconversion rates and anti-HBs titres were significantly greater in 1-4-year-olds than in older children (p less than 0.01). Eighteen children with no anti-HBs or other markers of HBV at this time were given 10 micrograms of vaccine and tested one month later. Seventeen developed anti-HBs, 12 at levels consistent with an anamnestic response. Forty-nine HBV-marker-negative children seroconverted for antibody to hepatitis B core antigen (anti-HBc) in the 8-month period before or the 12-month period following vaccination. Forty-six of these children were positive for anti-HBs, and one has been confirmed as a chronic carrier of hepatitis B surface antigen (HBsAg). Three cases of clinical hepatitis B in children have been seen in the community since the vaccination programme began. Two of these were amongst the estimated 5% of children who were not vaccinated. The third was in a vaccinee and occurred 4 1/2 months after the last dose of vaccine.(ABSTRACT TRUNCATED AT 250 WORDS)     

Immunological aspects of HBs antigenemia in patients with hematological malignancies

HBsAg positive sera of 70 patients with lymphoproliferative disorders were tested for hepatitis Be antigen (HBEAg) and antibodies to hepatitis B virus serum immunoglobulins: IgG, IgM and IgA were measured systematically in the whole group before and after acquisition of HBV infection. Sera of 37 patients with neoplastic disorders and of control group were also tested for antibodies to rubella virus (LRV). HBeAg was found in serum of 2 asymptomatic carriers of HBsAg, anti-HBs in serum of 2/70 patients who eliminated HBsAg from their serum within 3 months, anti-HBc were found in serum samples of all transient or persistent HBsAg positive patients. Substantial rise of IgG concentration was determined in the whole infected group irrespective of the clinical course. The percentage of patients without anti-RV was lower in HBsAg positive than in HBsAg negative patients. The differences in reactions to RV between cancer patients and control group were not significant. General impairment of humoral immunity or more specific defects are discussed as factors determining relative or absolute deficiency of anti-HBs and persistence of HBsAg in patients with lymphoproliferative disorders.     

Lamivudine prophylaxis and treatment of hepatitis B Virus-exposed recipients receiving reduced intensity conditioning hematopoietic stem cell transplants with alemtuzumab

Individuals with past exposure to hepatitis B virus (HBV) may reactivate HBV following bone marrow transplantation. Alemtuzumab (CAMPATH)-based reduced intensity conditioning bone marrow transplantation has been associated with a high incidence of viral infections. Lamivudine prophylaxis for HBV should be instituted in this setting. The management of 240 CAMPATH-based reduced intensity conditioning bone marrow transplantation, carried out over an 8-year period at Kings College Hospital, was reviewed. Hepatitis B core total antibody (anti-HBc) testing identified recipients and donors with previous HBV exposure. Fifteen donor-recipient pairs were identified as being at risk of HBV reactivation. Eight recipients of anti-HBc negative donors were HBsAg negative, anti-HBc positive pre-transplantation. Five anti-HBc negative recipients received transplants from HBsAg negative, anti-HBc positive donors. Two HBV carrier recipients had one anti-HBc negative and one positive donor, respectively. Pre-transplant lamivudine prophylaxis was given to 8/10 (80%) anti-HBc positive recipients. Although HBsAg and HBV DNA were detected 4 months after bone marrow transplantation in one patient who did not receive prophylaxis, a good antiviral response was documented on starting lamivudine. The two HBV carrier recipients had stopped lamivudine at 8 and 31 months post-bone marrow transplantation, respectively, and died of liver failure with a sharp rise in HBV DNA levels. The five anti-HBc negative recipients with anti-HBc positive donors remained HBsAg and HBV DNA negative. Although lamivudine prophylaxis prevented HBV reactivation, it is unclear at what stage post-transplantation prophylaxis can be discontinued. Close monitoring of liver function tests (LFTs), HBsAg, and HBV DNA must be undertaken even after stopping antiviral prophylaxis.     

Significance of isolated hepatitis B core antibodies detected by enzyme immunoassay in a high risk population.

Serum samples, which were found positive for anti-HBc and negative for HBsAg and anti-HBs during routine testing with Abbott enzyme immunoassays (EIA), were collected prospectively. The samples were obtained from patients with a high risk of hepatitis B. Further analysis was carried out using radioimmunoassays and tests for additional markers of hepatitis B. 84 of the 203 initially collected samples (41.4%) were found positive for anti-HBs by RIA. Of the 119 samples negative for anti-HBs by RIA, 103 were available for further investigation, and 35 (34.0%) of these were negative for anti-HBc by RIA. This indicates that low sensitivity of the anti-HBs EIA and non-specificity of the anti-HBc EIA may account for about 60% of the cases presenting with isolated anti-HBc at initial testing. Fifty-two samples positive for anti-HBc by RIA, with isolated anti-HBc confirmed after RIA testing for HBsAg and anti-HBs, were examined further: anti-HBe was detected in 16 sera, anti-HDV in one serum and HBV-DNA in 5 sera by PCR. Additional testing of serum samples with isolated anti-HBc is warranted.