Comparison of the second-generation digene hybrid capture assay with the branched-DNA assay for measurement of hepatitis B virus DNA in serum

The optimal hepatitis B virus (HBV) DNA quantitative assay for clinical use remains to be determined. We examined the sensitivity, linearity, and variability of a novel second-generation antibody capture solution hybridization assay, the Digene Hybrid Capture II assay (HCII), and compared it with another widely used solution hybridization assay, the branched-DNA (bDNA) assay (Quantiplex; Chiron Corp.). Our results showed similar and satisfactory assay linearity values, as well as interassay and intra-assay variability values, for both HCII and bDNA assays across different ranges of HBV DNA. Ninety-one percent of 102 serum samples from hepatitis B surface antigen-positive patients showed concordant results with the two assays. The HCII assay was more sensitive than the bDNA assay by 1 dilution, with the lowest reading being 0.9 pg/ml (3.8 pg/ml by bDNA assay). The HBV DNA seropositivity rates for the 102 samples were 58, 67, and 97% by bDNA, HCII, and nested PCR, respectively. While the relationship between results obtained with the bDNA assay and those with the HCII assay was nonlinear, with the bDNA assay yielding values 2.83 +/- 0.92-fold higher than those of the HCII assay, especially at high HBV DNA levels, a linear relationship was observed between the two sets of data after logarithmic conversion. The formula for interassay conversion of results was derived as follows: HBV DNA by HCII (picograms per milliliter) = 3.19 x [HBV DNA by bDNA (megaequivalents per milliliter)](0.866). The HCII assay was technically less complex and required a shorter assay time (4 h) than the bDNA assay (24 h). We conclude that the HCII assay compares favorably with the bDNA assay and offers the additional advantages of increased sensitivity and shorter assay time. The increased sensitivity should be particularly useful in monitoring the efficacy of antiviral therapies and detecting the emergence of drug-resistant HBV mutants.

Seroprevalence of markers for hepatitis B, C and G in male and female prisoners--NSW, 1996

OBJECTIVES

1. Establish the prevalence of markers for hepatitis B (HBV), C (HCV) and G (HGV) in a sample of male and female inmates. 2. Examine exposure to multiple viruses. 3. Compare risk factors for HGV infection with known risk factors for HBV and HCV.

DESIGN

Cross-sectional random sample stratified by sex, age and Aboriginality. Inmates were screened for three hepatitis markers. Participants were 789 inmates (657 male, 132 female) in 27 correctional centres in New South Wales, 1996.

RESULTS

Overall detection of each of the three screening markers was 35% for HBV, 39% for HCV and 10% for HGV. Exposure rates were higher in female prisoners than males. Increased rates of anti-HBc were observed in Aboriginal inmates compared with non-Aboriginals (54% cf. 27%); anti-HCV and HGV-RNA were comparable between the two groups (36% cf. 41% and 9% cf. 10%). Markers were significantly higher in female injecting drug users (IDU), particularly HCV (90% cf. 66%). Thirty-five per cent of inmates were unaware of their HCV status. For HBV, 72% did not self-report past or present exposure despite serological evidence to the contrary. The multivariate analysis identified Aboriginality, long-term injecting and injecting while in prison as risk factors for HBV. HCV risk factors were female sex, non-Aboriginality, institutionalisation and IDU-associated behaviours. For HGV, female sex and previous imprisonment were significant risk factors but IDU was not.

CONCLUSIONS

Blood-borne hepatitis viruses are common in prison inmates, particularly females (HBV, HCV and HGV), Aboriginals (HBV) and IDU (HBV and HCV). Infection can be related to a number of risk factors, which appear similar for HBV and HCV, but distinct from HGV.

A hepatitis B virus variant found in the sera of immunised children induces a conformational change in the HBsAg "a" determinant

The emergence of variants in the outer envelope proteins of hepatitis B virus (HBV) are found among individuals vaccinated against HBV and asymptomatic carriers of the infection. For example, children in The Gambia vaccinated against hepatitis B may show serological evidence of breakthrough infections, particularly if anti-HBs antibodies induced by the vaccine are low in titre. A single-point mutation at nucleotide 421 of the S gene is associated with such breakthrough infections. In the present study, the antigenicity of variant HBV S protein expressed as HBsAg particles in a vaccinia virus expression system has been characterised using a panel of monoclonal antibodies directed against linear and conformational determinations of the S protein. A cellular ELISA procedure using expressed antigen in Vero cells revealed differences in reactivity using four of the six antibodies that had been raised against the adw subtype of HBV and recognise conformational epitopes in the a determinant. In two instances, an enhanced reactivity for the variant antigen was found, confirming that point mutations in the a determinant of the S protein between residues 139 and 147 may result in significant changes in conformation. These findings also demonstrate that there are distinct antigenic differences between the vaccine strains of HBsAg/ adw subtype and the predominant HBsAg subtype circulating in West Africa. The implications of this work are that serodiagnosis of HBV infections may be unreliable in populations where there is a possibility of variant HBV infections emerging in the face of increasing herd immunity to HBV as a result of vaccination, particularly using monoclonal antibody-based diagnostic tests. Such variants may play a role in the maintenance of HBV infections in endemic regions.

[Interferon system status in hemodialysis patients infected with hepatitis B and C viruses]

The production of alpha- and gamma-interferon (IFN) by peripheral blood cells in vitro and the concentration of serum IFN were studied in patients treated by hemodialysis at the Pelgulinna Tallinn Hospital and compared to controls. Out of 108 patients on hemodialysis, 19.4% were infected with hepatitis B (HBV), and antibodies to hepatitis C virus (HCV) were detected in 7.4%. During 3.5 years of observation, cases of hepatitis B and C infection among patients and medical staff were rare. The production of alpha- and gamma-IFN in 23 patients with HBV and/or HCV markers on hemodialysis and in 38 patients without markers was similarly decreased in comparison with the controls and the titers of serum IFN were similarly increased. Lack of reliable difference between IFN status of two groups of patients may be explained by the absence of clinical symptoms of hepatitis, confirmed by laboratory findings.

[The assessment of the course of an infectious process by the membrane status of the peripheral blood lymphocytes]

Lipid peroxidation in lymphocyte membranes is studied in patients with acute viral hepatitis B and B + C and in chronic alcoholics with Flexner's dysentery and with uneventful premorbid history. The intensity of lipid peroxidation in lymphocytes was increased, corresponding to the severity and period of infection. The premorbid background and therapy influenced the lymphocyte membrane status, which can serve as an integral indicator of immunological reactivity of the organism.

Evaluation of serological screening of cadaveric sera for donor selection for cornea transplantation

Human corneas are explanted for grafting as late as 72 h after death, for example, from medical examiner cases. Currently, infection of the donor with human immunodeficiency virus (HIV), hepatitis B virus (HBV), and hepatitis C virus (HCV) is excluded in most cornea banks by serological testing of the cadaveric serum only. The reliability of this strategy was investigated by testing paired cadaveric and premortem sera of 33 potential donors. Results were discordant in 17 of 33 donors by at least one assay. Most frequently, HBsAg enzyme-linked immunosorbent assay (ELISA) yielded false-positive results with the cadaveric serum (16 of 33 serum pairs). Virus safety of the graft was affected in a single case, which was HCV antibody negative in the cadaveric serum, but positive in the premortem serum (confirmed by HCV-RIBA strip immunoassay). Forensic DNA profiling by polymerase chain reaction (PCR) of both serum samples confirmed that these were derived from the same individual. In conclusion, the results indicate that serological testing of cadaveric sera is not a reliable method for screening of potential cornea donors, and may not be sufficient for the virus safety of cornea grafts. Therefore, other screening strategies such as detection of viral nucleic acids by PCR should be evaluated.

Serological detection of hepatitis B virus genotypes by ELISA with monoclonal antibodies to type-specific epitopes in the preS2-region product

An ELISA was developed for serological determination of the six genotypes of hepatitis B virus (HBV) designated A, B, C, D, E, and F. Monoclonal antibodies were raised against genotype-specific epitopes in the preS2-region product, and labeled with horseradish peroxidase. Hepatitis B surface antigen (HBsAg) in sera was captured by immobilized antibodies against the common determinant, and evaluated for reactivity with genotype-specific monoclonal antibodies labeled with the enzyme. Serological genotyping was in complete accord with genotypes determined by S-gene sequences in a panel of 68 sera containing HBV/HBsAg of different genotypes. Of 514 sera with HBsAg from Japan, 507 (98.6%) were genotyped serologically: genotype A was identified in 24 (4.7%); B in 196 (38.1%); C in 282 (54.9%); D in 2 (0.4%); and F in 3 (0.6%). There were no sera containing HBV of genotype E. Likewise, 425 of 446 (95.3%) sera with HBsAg from Brazil, China, India, Indonesia, Kenya, Korea, Nepal, Papua New Guinea, the Philippines, and Thailand were classified into A (25.6%), B (24.2%), C (33.9%), and D (11.7%) genotypes; there were no sera with HBsAg of genotype E or F among them. Some sera unclassifiable by ELISA revealed mixed infection with HBV of distinct genotypes, or contained HBsAg deprived of genotype-specific epitopes by point mutations. The ELISA would be useful for large-scale surveys, because it allows serological detection of HBV genotypes without sequencing nucleotides.

Case-control study on hepatitis C virus (HCV) as a risk factor for hepatocellular carcinoma: the role of HCV genotypes and the synergism with hepatitis B virus and alcohol. Brescia HCC Study

We performed a case-control study to evaluate the risk of hepatocellular carcinoma (HCC) for hepatitis C virus (HCV) infection. A total of 305 newly diagnosed HCC cases (80% males) and 610 subjects (81% males) unaffected by clinically evident hepatic disease admitted to the 2 main hospitals in Brescia, North Italy, were recruited as cases and controls, respectively. Among the 122 HCC cases positive for HCV RNA, genotype 1b was found in 83 patients (68%), genotype 2 in 36 (29.5%) and genotype 1a in 3 (2.5%). Among the controls, 15 were infected with genotype 1b and 15 with type 2. Analysis of HCV envelope 1 nucleotide sequence among 25 cases and 8 controls infected with genotype 2 showed subtype 2c in 96% of cases and in all controls, and subtype 2a in 1 HCC case. The odds ratio (OR) for HCV RNA positivity adjusted for hepatitis B virus (HBV) markers and alcohol intake was 26.3 [95% confidence interval (CI): 15.8-44], and it was higher for genotype 1b (OR = 34.2) than type 2 (OR = 14.4). The OR for HCV RNA was 35.6 (95% CI: 14.5-87.1) when the HBV markers were all negative and 132 (15.3-890) when HBsAg positivity was present; the OR was 26.1 (95% CI: 12.6-54.0) among subjects with alcohol intake of 0-40 g/day and increased to 62.6 (23.3-168) and 126 (42.8-373) with an alcohol intake of 41-80 and >80 g/day, respectively. In conclusion, synergism was found between HCV infection and HBV infection and alcohol intake in causing HCC.

Hepatitis E in Damascus, Syria

A hospital-based study of acute hepatitis was conducted in Damascus, Syria, from 1995 to 1998. One hundred ninety-three sera from defined acute hepatitis cases were screened by ELISA for IgM anti-HAV, HBsAg, IgM anti-HBc and anti-HCV. Serum samples negative for all markers indicating recent infection by hepatitis A, B, or C were tested for HEV markers. Overall, 47 cases (24.4%) had no detectable hepatitis markers (non-A-E). HAV infection was detected in 71.2% of all viral hepatitis cases. Acute hepatitis B and C constituted 24 and 1.4% of the cases, respectively. Only five cases of acute hepatitis E were noted. Of 47 patients who had non-A-E hepatitis, fifteen (31.9%) tested positive for IgG anti HEV. This study provides indirect evidence that HEV is very likely to be endemic in Damascus, Syria. It reports for the first time the occurrence of hepatitis E in the country, a health problem that should be investigated further.

Lidocaine and monoethylglycinexylidide serum determinations to analyze liver function of cirrhotic patients after oral administration

Our aim was to compare standard liver function tests (serum bilirubin, serum albumin and prothrombin concentration), with lidocaine and monoethylglycinexylidide pharmacokinetic parameters, after oral lidocaine administration, to assess hepatic function of cirrhotic individuals. Twenty-one consecutive cirrhotic patients, nine consecutive acute hepatitis patients, and nine healthy individuals received oral lidocaine. Lidocaine and monoethylglycinexylidide serum concentrations were determined by the TDx system. Cirrhotic patients had higher lidocaine and lower monoethylglycinexylidide serum concentrations and differences in its pharmacokinetic variables, compared to control and hepatitis groups (P < 0.05). Sensitivity of lidocaine serum determinations (100%) was greater than sensitivity of serum bilirubin (57%), serum albumin (62%), and prothrombin concentrations (43%) and monoethylglycinexylidide serum concentrations (57%) in differentiating cirrhotic individuals from controls. In conclusion, after oral administration, lidocaine and monoethylglycinexylidide pharmacokinetic parameters are significantly altered in cirrhotic patients compared to normal and acute hepatitis subjects. Lidocaine pharmacokinetic parameters would be better than those of monoethylglycinexylidide and standard liver function tests in the evaluation of liver function of cirrhotic patients.

[Prevalence of serologic markers of hepatitis B virus in hospital personnel]

OBJECTIVE

To verify the prevalence of the anti-HBc, anti-HBs and HBsAg markers of hepatitis B virus, and to identify the risk factors determining occupational infection with this virus among hospital personnel.

METHODS

Samples of serum from 210 persons both male and female who work in different occupations at a hospital university, were analysed. The technique employed was the immunoenzymatic assay using commercial kits.

RESULTS

As a control group, samples of serum from 45 volunteer blood donors were utilized. It was verified that 20.5% of the hospital personnel presented a positive reaction to at least one of the markers songht, as against 6.6% of the control group. The prevalence of each marker separately was: anti-HBc 8.1%, anti-HBs 5.2%, and HBsAg 2.9% in the hospital personnel; and 4.4%, 2.2% and 0.0% in the control group. The simultaneous presence of the anti-HBc and anti-HBs markers was detected in 4.3% of the workers. In the control group, the presence of the anti-HBc and anti-HBs markers was detected, isolately, with respective prevalences of 4.4% and 2.2%. Those who presented the highest rates of positivite reaction were: laboratory technicians 24.0%, nurses 23.6%, physicians 20.8%, and cleaning personnel 18.2%.

CONCLUSIONS

The findings suggest that direct contact with patients and handling of blood and other body fluids are risk factors related to occupational infection with HBV. Therefore, it is recommended that hospital personnel be vaccinated against hepatitis B.

High pre-treatment serum hepatitis B virus titre predicts failure of lamivudine prophylaxis and graft re-infection after liver transplantation

BACKGROUND/AIMS

Orthotopic liver transplantation has an established role for the treatment of patients with chronic liver failure secondary to hepatitis B virus (HBV) infection. Unfortunately, recurrent infection of the graft can be associated with aggressive disease, and with diminished graft and patient survival. Currently, the role of nucleoside analogues for prevention of graft re-infection is being evaluated. Preliminary results are encouraging, but treatment failure has been associated with emergence of drug-resistant virus.

METHODS

We have studied ten consecutive patients who received lamivudine prophylaxis for prevention of HBV graft reinfection. Sequential sera, collected prelamivudine then during treatment before and after liver transplantation, were examined. Conventional serological markers were measured, as were serum viral DNA levels with a sensitive quantitative polymerase chain reaction assay.

RESULTS

Lamivudine treatment effected a reduction in serum HBV levels, but six patients still had measurable viral DNA at the time of transplantation. Five patients developed graft re-infection with lamivudine-resistant virus. Resistant virus emerged 8 to 15 months post-transplant. The likelihood of emergence of resistant virus was related to the pre-treatment serum HBV titre. Persistent serum viral DNA positivity and evidence of graft re-infection during the early post-transplant period did not predict the subsequent emergence of resistant virus.

CONCLUSIONS

Our observations suggest that the resistant species may be present in the viral quasispecies in the serum and liver of patients with high-level replication prior to lamivudine exposure. The resistant species can persist during lamivudine treatment prior to transplantation, and emerge following transplantation. These observations suggest strategies which might prevent the emergence of drug-resistant species, and imply that graft re-infection may be a preventable phenomenon.

Serum erythropoietin and interleukin-6 levels in hemodialysis patients with hepatitis virus infection

The influence of hepatitis B (HBV) and hepatitis C virus (HCV) infection on blood hemoglobin (Hb) and serum erythropoietin (Epo) and interleukin-6 (IL-6) concentrations was studied in 48 anemic patients on regular hemodialysis. They were grouped as follows: (I) 19 patients whose Hb values improved after infection (Hb > 85 g/L), (II) 10 patients with persisting anemia after infection (Hb < 75 g/L), and, without hepatitis virus markers (III) 8 patients with Hb > 85 g/L and (IV) 11 patients with Hb < 75 g/L. Serum immunoreactive Epo levels were significantly higher in group I (34.4+/-47.1 U/L) than in the other groups (II, 10.8+/-6.0; III, 7.9+/-3.2; IV, 8.4+/-4.3). Serum IL-6 was higher in group I than group III (7.7+/-7.8 pg/ml vs. 3.6+/-2.4; p = 0.05) but similar to the other groups. Hb levels in group I were maximal at the time of serum alanine aminotransferase normalization. Red cell production increases as a result of elevated circulating Epo during hepatic regeneration after HBV or HCV infection.

Prevalence of hepatitis B infection in the general population: a rural community based study

BACKGROUND

Available seroprevalence studies of hepatitis B in Indian population has limitations. A community based door to door epidemiological study was conducted between December 1997 and January 1988 to look for the dynamics of hepatitis B exposure in a single village of West Bengal.

METHODS

In all, 960 inhabitants out of 1261 (according to 91 census) in a village of Birbhum district in West Bengal were interviewed and their blood were tested by ELISA for HBV exposure. Odds ratio was calculated to estimate the relative risks for each potential factor facilitating virus transmission.

RESULTS

Participation rate in the present study was 76.1%. Over all HBsAg carrier rate was found to be 5.3%. Only 2/51 (3.9%) carriers were HBeAg positive. Injection by glass syringe (odds ratio = 3.01), age < 20 years (odds ratio = 1.41) and male sex (odds ratio = 1.57) were significant risk factor.

CONCLUSION

The results of this rural, predominantly poor, agrarian worker based community data reveals a fairly large reservoir of infection (5.3%). It is mainly built-up early in life. Injection practices need to be safer in addition to HBV vaccination to fight this menace.

Blood-borne virus infections in dialysis units--a review

Hepatitis outbreaks in haemodialysis unit patients and staff were reported in the late 1960s. In 1972, the Rosenheim report in the UK established guidelines which included routine tests for hepatitis B surface antigen and isolation facilities for dialysing patients with hepatitis B virus which resulted in a dramatic fall in cases of hepatitis. However, since these guidelines were introduced, other blood-borne viruses, notably HCV and HIV have been discovered, and failures of infection control practices still lead to outbreaks of HBV in haemodialysis units. The prevalence of HCV in dialysis patients varies considerably throughout the world, with reported prevalence ranging from 3.9% to 71%. The number of blood transfusions and the length of time on dialysis have consistently been associated with HCV prevalence. Several reports provide evidence of patient-to-patient HCV transmission with environmental blood contamination the most significant factor in intra-unit transmission. There is no evidence that HCV has been transmitted by re-use of dialysis machines but being dialysed next to an HCV positive patient is associated with a significant risk of HCV acquisition. Several studies have shown that dialysing HCV positive patients in a separate unit or in a defined sector of a dialysis unit significantly reduces nosocomial HCV infection. HGV is prevalent in dialysis units where there is evidence of transmission to patients but no evidence of associated symptoms. HIV is infrequently transmitted in dialysis units and several units treating many HIV-positive patients have shown no evidence of transmission. Careful attention needs to be paid to infection control procedures and regular virological testing.

High prevalence and phylogenetic analysis of TT-virus infection in Mongolia

A novel DNA virus, TT-virus (TTV), was isolated from a post-transfusion hepatitis patient in Japan. The prevalence of TTV infection was investigated among patients with chronic liver disease and normal alanine aminotransferase (ALT) volunteers as controls in Mongolia. Polymerase chain reaction (PCR) was employed to detect TTV DNA using specific primers derived from open reading frame 1 (ORF1) of the TTV genome. Nucleotide sequences of samples positive for TTV DNA were determined. The sequences were analyzed by a molecular evolutionary method. Fifty (60.2%) hepatitis patients and 12 (42.9%) volunteers were positive for TTV DNA. The serum ALT levels did not differ significantly between patients with single TTV infection and without TTV, HBV and HCV infection. Similarly, the serum ALT levels did not differ significantly between controls with and without TTV infection. Dual infection of TTV with either HBV or HCV did not affect the ALT levels of hepatitis patients. The molecular evolutionary tree showed that TTV was a heterogeneous virus and all strains could be divided into three genotypes in Mongolia. A new genotype was identified that was distinct from those previously reported.

Mutations in the basic core promotor and the precore region of hepatitis B virus and their selection in children with fulminant and chronic hepatitis B

The involvement of precore stop codon 1896-A and base exchanges in the AT-rich region at positions 1762 and 1764 of the hepatitis B core promotor has been controversely discussed in adults with fulminant hepatitis B. Because no data are currently available on children, we analyzed the basic core promotor (BCP) and precore region in children with chronic and fulminant hepatitis B. The BCP and precore region were sequenced directly and after cloning from mothers and infants. Thirteen children suffered from chronic liver disease, 6 of whom were treated with interferon alfa (IFN-alpha). All 13 patients seroconverted from hepatitis B e antigen (HBeAg) to hepatitis B e antigen antibodies (anti-HBe), and sera were analyzed before and after seroconversion. Nine vertically infected infants developed a fulminant course of hepatitis B. The occurrence of BCP (1762-T/1764-A, 7.7%) and precore (1896-A, 7.7%; 1899-A, 15%) mutations in chronic hepatitis B was rare. A genotype shift from D to A was observed in 3 patients after development of anti-HBe. A high number of base exchanges was detected in those infants with fulminant hepatitis B. Eight of nine showed a G-A exchange at positions 1896/97 (89%), 1899 (56%), and/or mutations at nucleotide (nt) positions 1762 (56%) and 1764 (78%). All virus strains belonged to genotype D, whereas in the only surviving infant, a D-to-A shift was detected. Hepatitis B virus (HBV) DNA clones were examined from 3 babies and 5 mothers. Our results showed a heterogeneous virus population in 4 of 5 mothers. In contrast, a homogeneous virus population emerged in the infants. According to our data, the analysis in children with fulminant and chronic hepatitis B revealed a striking presence of BCP and precore mutants in infants with fulminant hepatitis (FH) when compared with clinically inapparent anti-HBe-positive children (P <.002), which could be one factor in the pathogenesis of fulminant hepatitis B in children.

[Study on hepatitis G virus infection]

OBJECTIVE

To find out the situation of HGV infection in Shandong Province, and to explore the relations between HGV infection and HCV or HBV infection.

METHODS

Enzyme linked immunosorbent assay (ELISA) was used to determine the serum anti-HGV in 1,082 patients with viral hepatitis, 77 patients with non A-E hepatitis and 361 blood donors.

RESULTS

53 patients whose serum anti-HGVs were positive (positive rate: 3.49%) were noticed. The anti-HGV positive rate (8.93%) in patients with Hepatitis C was remarkably higher than that (3.32%) in patients with Hepatitis B (chi 2 = 8.80, P < 0.01). The anti-HGV positive rate (4.82%) in patients with chronic hepatitis was significantly higher than that (0.79%) in patients with acute hepatitis (chi 2 = 10.79, P < 0.01). The anti-HGV positive rate (8.00%) in patients with severe hepatitis was obviously higher than that in patients with acute hepatitis (chi 2 = 10.23, P < 0.01).

CONCLUSION

The manifestations of HGV infection can be expressed as virus-carriers, subclinical infection or various clinical types. Patients with Hepatitis C were more subjective to be overlapped with HGV than the patients with Hepatitis B; moreover, HCV or HBV infection superinfected with HGV is associated with exacerbation of patients' condition and the formation of chronic infection.

Guidelines for serological testing in the diagnosis of acute hepatitis A and B

This study was performed to determine whether elevation of serum transaminases can be used to eliminate unnecessary serological tests to diagnose acute hepatitis A (HAV) and acute hepatitis B (HBV). Serum samples of 1226 patients were tested for HBsAg, anti-HBc (IgM), and anti-HAV (IgM). Acute hepatitis was diagnosed in 113 (9.2%) patients; 75 were serologically positive for HAV, 36 for HBV, and 2 patients for both HAV and HBV. Serum transaminase levels were elevated in 104 of 107 (97.2%) of seropositive patients in whom the results of biochemical tests were available. A review of the medical records of seropositive patients with normal transaminases revealed that each of the three HAV patients had a remote history of hepatitis. None of the seropositive patients with a recent history of acute viral hepatitis had normal transaminase levels. During this period, serological tests were ordered in 266 of 1054 (25.2%) seronegative patients with normal serum transaminases. We conclude that serum transaminase levels can be reliably used to screen sera for acute HAV and HBV infection.

[The serum insulin level in severe hepatitis patients]

Serum insulin (SI) levels were determined in 36 severe hepatitis patients by RIA. The average level of SI in chronic severe hepatitis (CSH) patients was 43.18 +/- 27.12 mu.L-1, and subacute severe hepatitis (SSH) patients 28.91 +/- 12.77 mu.L-1. Both were increased significantly as compared with normal controls (P < 0.01), and the level of SI in patients died from SSH and CSH was increased significantly than those alive (P < 0.05). The level of SI at the fastiguium stage of the disease was significantly higher as compared with that of the convalescence stage (P < 0.05). The results suggest that SI may aid to evaluate the severity of the illness and to estimate the outcome of the patients.

[Functional status of the interferon system in inapparent and clinical infection with hepatitis B and C viruses]

In vitro production of alpha- and gamma-interferon (IF) by peripheral blood cells and the concentrations of serum IF were studied in 47 intravenous drug users infected with hepatitides viruses B and C (HBV and HCV) and in 50 inpatients with verified diagnosis of hepatitides B or C, 16 of these narcomaniacs. In acute disease, the capacity of cells to produce alpha- and gamma-IF was suppressed, while the concentration of IF circulating in the blood was increased. Suppression of alpha-IF production was more expressed in patients with hepatitides C and B+C than in those with hepatitis B. HBV and/or HCV infection without clinical signs of disease did not affect the production of IF. In narcomaniacs using opiates and ephedrine drugs for up to 5 years IF system did not depend on drug addiction.

Discrimination of two different clinical entities, acute-type and subacute-type, human fulminant hepatitis by peripheral blood lymphocyte subsets

Human fulminant hepatitis tends to be classified into two groups: acute type (A-FH) and subacute type (S-FH). In order to define these two clinical entities more precisely, we examined and compared peripheral blood lymphocyte subsets in A-FH and S-FH patients. We found that S-FH patients had a higher prevalence of CD19+ B cells (31.1 +/- 7.6% in S-FH vs 12.7 +/- 3.7% in A-FH) and also a lower prevalence of CD3+T cells (50.2 +/- 8.7% in S-FH vs 65.6 +/- 10.5% in A-FH). Furthermore, by examining the absolute cell numbers of these subsets, we determined that their imbalance in S-FH was mainly due to a decrease in CD3+ T cells. Among several T cell subsets, the CD8+CD11b-T cell subset was elevated in A-FH and decreased in S-FH (6.1 +/- 2.1% in S-FH, 24.4 +/- 5.8% in A-FH, and 14.8 +/- 7.8% in control). Serial studies of two S-FH patients revealed that the imbalance of these lymphocyte subsets returned to their proper ratio together with the improvement of their liver injury. These results indicate that there might be a different immunological background between A-FH and S-FH.

Hepadnavirus evolution and molecular strategy of adaptation in a new host

In order to elucidate the mechanisms of hepadnavirus evolution in vivo and to trace the fate of known quasispecies in a single animal during the acute phase of infection, a woodchuck (Marmota monax) was infected with the hepadnavirus woodchuck hepatitis B virus (WHV). Woodchuck 197 (W197) was injected intravenously with pooled sera collected from a chronic carrier that had been infected originally with a molecular clone of known genome sequence (WHV7). Viral genome variants from both the inoculum and the follow-up sera from W197 were characterized for the presence of quasispecies related to the WHV7 sequence. Interestingly, WHV7-related genomes were predominant 6 weeks post-infection (p.i.), whereas a highly heterogeneous virus population was present in the first viraemic serum (4 weeks p.i.). Using WHV7 as the prototype, the variability of the Pol and PreS/S regions in the first 11 weeks p.i. has been calculated. The sequence population in serum collected 6 weeks p.i. was highly homogeneous, with a mean variability of 0.36% in the region analysed. Mean variability values ranging from 0.82% to 1.61% were found in quasispecies from the other sera. The presence of possible selective pressure was analysed by means of the non-synonymous versus synonymous variation ratio (dn/d5). We found that the dn/d5 values were stable for the S ORF (ranging from 2.6 to 3.0), whereas a wider range was observed for the Pol ORF (from 1.4 to 3.0). Furthermore, from the analysis of the variability of the codon positions for the two overlapping ORFs it was found that, in most cases, non-synonymous mutations at position 1 of the Pol ORF (position 3 of the S ORF) corresponded to synonymous variation in the S (Pol) ORF, indicating independent evolution of the encoded proteins.