Relationship between hepatitis B virus DNA in blood and serological markers of hepatitis B infection

Detection of hepatitis B virus in seropositive and seronegative patients with chronic liver disease using DNA amplification by PCR

BACKGROUND

The aim of this study was to detect DNA of hepatitis B virus (HBV) for reliable diagnosis of HBV infection in sera by means of a validated polymerase chain reaction (PCR) using a 5' oligonucleotide (primer) previously described and a 3' primer designed by our investigation group.

METHODS

Sera samples collected from patients with chronic liver disease (CLD) related to HBV infection and negative to hepatitis C virus (HCV) infection were analyzed. Patients were both positive and negative to HBV by serum markers detected by ELISA immunoassay. A 146-base pair (bp) fragment was amplified from highly conserved precore-core region. This procedure enabled us to search for DNA HBV-positive cases.

RESULTS

Viral replicative state in negative hepatitis B e antigen (HBeAg) (15.7%) cases was verified by PCR technique. This detected infection by HBV in 100% of immunoassay-positive samples. Additionally, sequences of expected size in patients bearing atypical markers in their sera (7.1%) and those with negative serology (4.8%) for HBV markers were detected.

CONCLUSIONS

In this study we have improved a PCR technique successfully applied in hepatitis B prevalence studies in northeastern Mexico. Prevalence of hepatitis B in this region of Mexico is intermediate compared to countries of the northern hemisphere where prevalence is lower, and to countries of Southeast Asia and the Mediterranean region where it is highly endemic.

Coinfection with hepatitis B and C or B, C and delta viruses results in severe chronic liver disease and responds poorly to interferon-alpha treatment

Chronic coinfection with the hepatitis B (HBV) and hepatitis delta (HDV) viruses is known to cause severe liver disease, but the importance of coinfection with hepatitis C virus (HCV) and HBV has not been well documented. In the present study, the clinical and pathological severity of liver disease among patients with hepatitis resulting from multiple viruses was examined and an open trial of the efficacy of interferon-alpha 2b (IFN-alpha) treatment was conducted. Nineteen patients with chronic HBV and HCV infection and 17 with HBV, HCV and HDV infection were studied; 12 in each group underwent liver biopsy. For each coinfected patient, two patients infected with HCV alone were selected as controls, and these were matched for age and risk factor and were estimated to have been infected for a similar duration. Coinfection with HBV and HCV or HBV, HCV and HDV was associated with more severe liver disease than HCV alone (P < 0.01); total Scheuer score, portal and lobular inflammation and fibrosis were all worse in coinfected subjects. Eight patients with chronic HBV and HCV were treated with recombinant IFN-alpha 2b [3 million units (MU), thrice weekly for 6 months]. Liver function tests normalized in two patients and one lost hepatitis B surface antigen (HBsAg). Seven patients with hepatitis B, C and delta coinfection were treated with the same regimen and only one normalized serum alanine aminotransferase (ALT) during (and after) treatment. It is concluded that coinfection with multiple hepatitis viruses is associated with histologically more severe liver disease than HCV alone.(ABSTRACT TRUNCATED AT 250 WORDS)

Histopathological prediction of hepatitis B recurrence in liver allografts

The aim of this study was to review the clinical, serological and histopathological features of 20 patients who underwent orthotopic liver transplantation for hepatitis B virus (HBV) related liver disease in an attempt to identify factors which predict recurrence of HBV infection, pattern of disease and disease severity. Hepatitis B recurrence occurred in 11 patients (55%). Positive immunoperoxidase staining for HBsAg and HBcAg of the hepatectomy specimen were shown to have a sensitivity (82% and 64% respectively) and specificity (55% and 66%) in predicting recurrence. This was comparable to serological markers such as HBV DNA (36% sensitivity and 89% specificity). The staining for HBcAg in some cases was weak, focal and had a reticular pattern. Therefore, examination of multiple blocks with a high magnification was necessary to detect HBcAg staining. Negative staining of multiple sections for HBsAg and HBcAg were shown to have a good correlation with clearing of HBV infection (5 out of 6 patients). If recurrence occurred, the range of histological and clinical patterns of HBV recurrence was varied, with severe disease occurring in 5 patients. Neither pre-transplant serology nor hepatectomy immunoperoxidase staining characteristics were shown to be of value in predicting the pattern or the severity of disease once HBV recurrence had occurred. This study indicates that lack of staining for HBV antigens on multiple sections of the native liver may predict a subgroup of HBsAg positive transplant patients who will not suffer from recurrent disease. Once disease did occur however, markers for severity of recurrence were not identified.

Pre-core mutation associated with lack of hepatitis B e antigenaemia in Moroccan asymptomatic carriers of the virus

Recently, ongoing chronic liver disease with persistent viraemia has been described in hepatitis B virus (HBV) carriers despite the presence of anti-HBe. This has been attributed to infection with pre-C-region-mutated HBV variants. To investigate the possible existence and the prevalence of HBV variants in Morocco and the correlation between HBV DNA detection by polymerase chain reaction and pre-S1 antigenaemia, we tested twenty blood donors, HBsAg chronic carriers for more than one year. The diagnosis of such HBeAg-negative HBV variants was determined by a previously described rapid detection method using selective oligonucleotide hybridization. Probes M0, M1 and M2 correspond, respectively, to a non-mutated distal pre-C sequence, a one-point-mutated sequence with a TAG stop codon at pre-C codon 28 and a two-point-mutated sequence with codon 28 TAG and codon 29 GAC. All the 5 HBeAg-positive samples hybridized with the M0 wild-type probe only. Among the anti-HBe-positive samples, one hybridized with the M0 probe only, whereas another hybridized with none of the oligoprobes. The 13 remaining HBeAg-negative cases hybridized with the M1, M2 or combined M0, M1 and M2 probes. Seven of the 13 HBeAg-negative samples hybridized with more than one probe. DNA sequencing confirmed mixed distal pre-C sequence changes in samples hybridizing with more than one probe. These data demonstrate the existence, in patients, of HBV variants containing an inactive pre-C region and hence the incapacity to synthesize pre-C-region-derived HBeAg.

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)

Relevance of hepatitis B DNA detection in patient's serum

Detection of HBV-DNA showed a satisfactory sensitivity (6 pg/ml) and high specificity: 15 patients with hepatitis A, 6 with CMV, 7 with EBV infection, 81 with hepatitis NANB as well as 174 persons with isolated HBc antibodies and 9 hepatitis B vaccinees gave negative results. However, out of 118 persons with a history of hepatitis B (HBs and HBc antibodies positive), one repeatedly had a positive result. We followed 58 patients with chronic hepatitis B, 25 healthy antigen carries, and 16 HBV-infected dialysis patients over an extended period with multiple blood sampling. Most of those patients showed changes of detectability of HBV-DNA. Typically, periods with positive DNA tests were followed by intervals with negative tests which could last for up to a few years. 75% of dialysis patients were positive in all sera available, while 48% of healthy antigen carriers were consistently negative. Additionally, 9 patients with a history of recent hepatitis B and a positive HBs antibody test as well as 4 patients with simultaneous infection by A and B were tested for HBV-DNA. In none of these two groups, a variation from the pattern usually found in hepatitis B was established. A case of intrauterine infection with hepatitis B virus is reported. Because the blood of the mother was free from HBV-DNA and HBe antigen at delivery and because the hepatitis B immunoglobulin prophylaxis failed in the child who developed HBs antigen very soon after delivery, it has been concluded that the child was infected in utero. The highest values of HBV-DNA determined quantitatively were found in dialysis patients which explains the high risk of acquiring hepatitis B in the dialysis unit. The results from earlier studies on the prognostic relevance of HBV-DNA and the risk of medical personnel as a source of infection with hepatitis B are discussed briefly.

Potential infectivity of blood from HBsAg asymptomatic carriers due to the presence of HBV-DNA and comparison with other markers of HBV infection

Serum samples from 356 HBsAg positive asymptomatic carriers, which were titrated by reverse passive hemagglutination, were analysed for the presence of HBV-DNA, HBsAg and IgM anti-HBc. The samples were divided in three classes, according to the titers of HBsAg and IgM anti-HBc and the distribution of HBV-DNA and HBsAg among these classes was studied. In the high titer class of HBsAg, 65% of samples have one or both markers against only 19% in the low titer class. From the total of 356 samples, 121 gave positive results for IgM anti-HBc (33.9%). From these, 38.9% of HBV-DNA and 47.9% of HBeAg were observed, whereas in samples with absence of IgM anti-HBc, 18.3% and 16.6% were respectively found. A higher frequency of agreement between all these markers was found in the class of high titers of HBsAg; however, HBV-DNA was detected in the low titer class of HBsAg and little or no IgM anti-HBc, showing potential blood infectivity even in HBsAg positive borderline samples.

Serial antipyrine clearance studies detect altered hepatic metabolic function during spontaneous and interferon-induced changes in chronic hepatitis B disease activity

The present study was performed to establish whether sequential determinations of antipyrine clearance, using a simplified two-point test, are sensitive and specific indicators of changes in chronic hepatitis B disease activity. Sixteen patients were studied on four or more occasions during 18 to 30 months. Eleven patients were treated with recombinant human alpha-interferon (2.5, 5.0 or 10 X 10(6) per m2, intramuscularly, three times per week, for 24 weeks), and five patients were untreated controls. Among seven patients, (six interferon-treated and one control) who lost hepatitis B e antigen from serum, antipyrine clearance improved by 46% (range: 20 to 160%) from 0.37 +/- 0.14 ml per kg per min (mean +/- S.D.) to 0.54 +/- 0.13 ml per kg per min, p less than 0.005. This change paralleled the loss of symptoms and reduction of serum ALT levels (from 206 +/- 189 IU per liter (mean +/- S.D.) to 38 +/- 12 IU per liter, p less than 0.005). Conversely, antipyrine clearance declined to previous levels when reactivation of chronic hepatitis B with reappearance of HBeAg in serum occurred. Regardless of changes in hepatitis B serology, when serum ALT values fluctuated by more than 20% (presumed to reflect fluctuations in necroinflammatory activity of the liver disease), antipyrine clearance also changed whereas serum albumin and bilirubin concentrations and prothrombin time did not. It is concluded that antipyrine clearance is a more sensitive and specific parameter than conventional indices for assessing hepatic metabolic function during changes in chronic hepatitis B disease activity. Remission in disease with loss of HBeAg from serum is associated with improved hepatic metabolic function as determined by the antipyrine clearance test.

Hepatitis B virus replication in hepatitis B and D coinfection

The clinical course, changes in liver function tests and the behaviour of viral markers over the course of time have been examined in 45 patients with acute hepatitis B and 14 patients with acute hepatitis caused by B and D viruses coinfection. There were no significant differences either in the clinical course or in the liver function tests, in the two groups. The changes in serum viral markers were as follows: HBV-DNA was the first marker to disappear; this was closely followed by HBeAg, and HBsAg was the last marker to become negative, during convalescence. This pattern was not altered by Delta coinfection. When we quantified serum HBV-DNA in both groups of patients, we found that Delta virus infection led to parital inhibition of HBV replication, so that serum HBV-DNA levels were significantly lower in those patients with acute hepatitis B who were simultaneously infected with Delta virus.

Infectivity of medical staff for hepatitis B

Prior to hepatitis B vaccination, 36,000 persons of the medical staff were tested for HBs antigen, HBc antibodies, and HBs antibodies. 210 sera were found positive for HBs antigen and HBc antibodies. Of these sera, 171 were available for testing for hepatitis B virus DNA as a marker of infectivity by spot hybridization. DNA was detected in only 15. One hundred and thirty-nine had HBe antibodies but no detectable HBe antigen, and only two of these were hepatitis B virus DNA positive. 12 had neither HBe antigen nor HBe antibodies and none had hepatitis B virus DNA. Hepatitis B virus DNA was, however, detected in 13 of 20 HBe antigen-positive but HBe antibody-negative sera. Our study confirms epidemiological observations that medical staff hardly plays any role as a source of HBV infection for patients.

Relationship between HBeAg and HBV DNA in patients with acute and persistent hepatitis B infection

The correlation between hepatitis B e antigen (HBeAg) and hepatitis B virus (HBV) DNA was studied in a number of hepatitis B surface antigen (HBsAg)-positive serum samples which had been submitted for routine hepatitis screening. In patients with either acute or persistent HBV infection, a good overall correlation between HBeAg and HBV DNA was noted, although in persistently infected patients with chronic liver disease, 28% of samples with hepatitis B e antibody (anti-HBe) were also positive for HBV DNA. Around 3% of the samples that were positive for HBV DNA were negative for HBeAg and anti-HBe while, conversely, 19% of HBeAg-positive sera were negative for HBV DNA. These results indicate that the presence or absence of HBeAg/anti-HBe may not necessarily reflect that of serum HBV DNA, particularly in persistent infection; this provides further support for the replacement of HBeAg/anti-HBe assays by detection of HBV DNA in the routine assessment of possible infectivity and chronic liver disease in HBsAg-positive patients.