[Hepatitis C virus antibodies in 34130 blood donors in Tunisian Sahel]

Since January 6th 1994 to december 31 1997. We researched hepatitis C Virus antibodies by second and third generation ELISA in 34,130 bloods donors living in "Sahel Tunisien". 193 were positive (0.56%). Only 171 of them were secondary tested by immunoblot assay (anticore, anti NS5, anti NS3, anti NS4). Which was positive in 53 cases (30.9%); in determined (presence of only one antibody) in 78 cases (45.6%) and negative, in 40 cases (23.3%). There was a significant relation between a ratio over than 2.5 in ELISA and immunoblot positivity. Immune response to different hepatitis virus antigens were heterogeneous with predominant in determined profile. (78/171 cases). Most of donors of the last profile had either anti NS5 (32/78) or anti NS3 (33/78) and we excluded them even through usually negative in P.C.R and associated with a very low risk of contamination.

NAT: perspectives for cellular components

The introduction of routine testing to detect viral genomes in donated blood was originally driven by requirements for plasma fractionation in relation to exclusion of hepatitis C virus (HCV) RNA. Nevertheless, it was obvious from the outset that a dual standard for fractionated products and individual blood components would be untenable. In many countries therefore, planning for introduction of nucleic acid testing (NAT) of blood incorporated progression to release of HCV RNA tested components. HCV was singled out because of its long seronegative 'window period', relatively high prevalence and incidence in blood donors, rapid burst time and high genome copy number during seroconversion. The latter properties made HCV particularly suitable for detection in pools of samples. If HCV RNA testing is required for release of labile components such as platelets, rapid provision of NAT results is vital because of short shelf life of platelets and the problems of delays when resolving the infectious unit in a reactive pool. For NAT release of labile components smaller sample pool sizes allow faster resolution of RNA positive units. Smaller pools involve high test throughput, the likely need for more testing laboratories and ensuing increased costs. Single sample testing is the ultimate extrapolation of reducing sample pool size. With reduced pool sizes or single sample testing, the option of testing for other viruses (e.g. HIV or HBV) singly or in multiplex also arises. The cost-benefit and incremental yield of such strategies in the light of 'combo' assays for HIV Ag/Ab and the recently described HCV Ag assay will require careful and objective assessment, together with re-appraisal of anti-HBc screening for detection of HBV infected donors at the "tail-end" of carriage.

Quantification of serum HCV core antigen by a fluorescent enzyme immunoassay in liver transplant recipients with recurrent hepatitis C--clinical and virologic implications

BACKGROUND

Monitoring hepatitis C viremia may be useful in the management of liver transplant patients with recurrent hepatitis C virus (HCV) infection. The clinical utility of a newly described fluorescent enzyme immunoassay for the detection of serum HCV core antigen was evaluated.

METHODS

Serum samples prospectively collected from 57/63 consecutive patients transplanted for HCV-related end-stage liver disease were assayed for both serum HCV core antigen by fluorescent enzyme immunoassay and HCV RNA level using a branched chain DNA signal amplification assay. HCV genotype was determined by restriction fragment length polymorphism analysis based on 5' untranslated region. One- and 2-year annual protocol liver biopsies from these patients were graded for inflammation, fibrosis, and cholestasis

RESULTS

Serum HCV core antigen and HCV RNA were detected in a similar proportion of samples (256/ 281 vs. 260/281, P=NS), and there was an excellent correlation between assays (r2=0.905, P<0.0001) independent of HCV genotype. A conversion equation between HCV core antigen and HCV RNA was constructed to estimate the HCV core antigen to RNA ratio to be around 231 to 1. Mean serum HCV core antigen levels peaked initially at 3 months posttransplant but there was significant interpatient variation as to when peak levels occurred. A high serum HCV core antigen level in the first 6 months was associated with histological deterioration in terms of bridging fibrosis, cirrhosis, severe cholestasis, or retransplantation by 2-year follow-up.

CONCLUSION

Determination of serum HCV core antigen level reflects HCV viremia and may have clinical implications in liver transplant patients with HCV recurrence.

[The significance of detection of hepatitis C virus RNA in peripheral blood mononuclear cells of patients with chronic hepatitis C]

OBJECTIVE

To determine the role of peripheral blood mononuclear cells (PBMCs) in hepatitis C virus (HCV) infection.

METHODS

HCV RNA, HCV antigen and Fas antigen were detected in PBMCs of 22 patients with chronic hepatitis C, 21 renal dialysis patients with anti-HCV positive and 12 health blood donors as normal controls. All specimens were studied by electronic microscope (EM).

RESULTS

(1) The positive rate of HCV RNA in PBMCs of 22 patients with hepatitis C was 77.3% (17/22). (2) EM showed that HCV particles replicated in PBMCs of the patients with HCV infection, but not in the serum of patients with negative HCV RNA and healthy controls. (3) HCV RNA were positive both in the serum and PBMCs of 8 patients with HCV particles positive and had a close relationship with HCV antigen and Fas antigen. The expression of HCV and apoptosis were found in the cytoplasm of PBMCs in these 8 patients.

CONCLUSION

(1) Hepatitis C virus could replicate in PBMCs and produce infectious HCV particles. (2) HCV in PBMCs may act as the source of reinfection for HCV and lead to persistent infection and recurrence.

Hepatitis B and C virus markers among new entrant medical students

AIM

To investigate the presence of hepatitis B and C virus markers in new entrant medical students at the Faculty of Medicine, University of Kelaniya.

METHOD

456 students (mean age 24 years, SD 3.5, 257 men) were investigated before they were exposed to clinical work, using a questionnaire to assess sociodemographic factors and possible risk factors for contracting hepatitis B or C. Blood samples were tested for HBs Ag and anti HBs (n = 456), and anti-HCV (n = 162 randomly selected samples) with a third generation sandwich radioimmunoassay technique.

RESULTS

The students were from 20 of the 25 districts in the country, although their distribution was not inform. A past history of hepatitis or jaundice was obtained from 24 (5.3%) and 6 (1.3%) students respectively. None of them had been vaccinated against hepatitis B. At least one risk factor for hepatitis B or C was present in 32 (7%) of them. None of the samples were positive for HBsAg or anti-HCV, and only two (0.44%) were positive for anti-HBs.

CONCLUSION

Our results support the view that exposure to hepatitis B and C seems to be uncommon in this country, at least up to young adulthood. As most new entrant medical students are not immune to these infections there is a strong case to vaccinate them against hepatitis B before they are exposed to clinical work.

Low levels of hepatitis C virus RNA in serum, plasma, and peripheral blood mononuclear cells of injecting drug users during long antibody-undetectable periods before seroconversion

Screening of antibodies to hepatitis C virus (HCV) is widely used for monitoring the prevalence of HCV infections and to assess HCV infectivity. Among HCV-infected individuals in the general population, the interval between the detection of HCV RNA and the development of HCV antibodies is usually 5 to 6 weeks, but in rare cases, seroconversion may be prolonged up to 6 to 9 months. In this study, we tested for the presence of HCV RNA during the antibody-undetectable period of 19 drug-injecting HCV seroconverters to gain insight into the antibody-negative carrier status in this population. HCV seroconversion status was determined by testing the first and last serum samples obtained from each subject, using third-generation antibody screening and confirmation assays. Serial samples were tested for HCV-specific antibodies to establish the moment of seroconversion and HCV RNA by single reverse transcriptase-polymerase chain reaction (RT-PCR) and branched DNA assay (bDNA) in serum. Plasma and peripheral blood mononuclear cells (PBMCs) were independently collected and tested for HCV RNA. HCV RNA-positivity was confirmed by Southern blot hybridization and sequencing of serial samples. The 19 HCV seroconverters had a mean follow-up of 5 years (range, 1 to 8 years). Of the 19, 4 were human immunodeficiency virus (HIV)-infected before HCV seroconversion. HCV RNA was detected in serum before seroconversion in 12 (63.2%) of the 19 HCV seroconverters, independent of HIV status. In 7 of these 12, the antibody-undetectable period was relatively short (2 to 10 months). The other 5, who were all HIV-negative before HCV seroconversion, had intermittent low levels of HCV RNA before seroconversion for a period of more than 12 months, with a mean of 40.8 months (range, 13 to 94 months). In all 5 individuals, independent repeats of the experiments confirmed the presence of HCV RNA in serum, and in 3 of these individuals, HCV-positivity was confirmed in independently collected plasma and PBMC samples. Low levels of HCV RNA may be present during prolonged antibody-undetectable periods before seroconversion in a number of injecting drug users. Independent of HIV status, their immune system appears to be unable to respond to these low HCV RNA levels and was sometimes only activated after reinfections with distinct HCV genotypes. These results indicate that primary HCV infection may not always elicit the rapid emergence of HCV antibodies and suggests that persistent low levels of HCV RNA (regardless of the genotype) may not elicit at all or delay antibody responses for prolonged periods of time.

Chronic liver disease and hepatitis C virus in Egyptian patients

BACKGROUND/AIMS

This study was designed to evaluate anti-HCV and anti-GOR in chronic liver disease (CLD) caused by HCV alone or with bilharzia.

METHODOLOGY

The parameters of hepatitis C virus (HCV) infection among 45 chronic liver disease (CLD) patients are the subject of this study. The samples that were collected included serum, saliva and liver biopsy. For comparison, 44 serum, saliva and liver biopsies were also collected from non liver disease (NLD) patients undergoing surgery at the Gastroenterology Surgical Center, Mansoura University.

RESULTS

Screening of antihepatitis C (anti-HCV) with a second generation ELISA test showed that 37/45 (82.2%) sera and 17/45 (37.7%) saliva samples from CLD patients were positive for the presence of anti-HCV (IgG), while, anti-HCV (IgG) was detected among 32/44 (72.7%) sera and 6/44 (13.6%) saliva samples from NLD patients. HCV antigen was detected by immunostaining in the liver biopsy sections of 11/45 (24.4%) CLD and in 6/44 (13.6%) NLD patients. HCV antigen was detected in hepatocyte cytoplasm and nuclei, in some endothelial cells lining the hepatic cell cords, and in some bile duct cells. The serum and saliva samples from both CLD and NLD patients were also tested by ELISA for the presence of anti-GOR to determine the prevalence of autoantibody in HCV infected and non-infected patients. Anti-GOR was detected in 19/45 (42.2%) sera and in 1/45 (2.21%) saliva samples from CLD patients, while in the case of NLD patients, anti-GOR antibodies were found in 7/44 (15.9%) sera and in 4/44 (9%) saliva samples. GOR antigen was detected by an indirect immunoperoxidase stain of liver biopsies. Positive GOR antigen signals were found in hepatocytes but granular cytoplasmic, and extrahepatic localization was also noticed. A correlation between the detection of anti-GOR and anti-HCV revealed that, out of 37 anti-HCV positive CLD patients, there were 19 (51.3%) positive for anti-GOR, while 7/32 (21.8%) NLD patients were positive for anti-HCV and for anti-GOR.

CONCLUSIONS

The results of the present study confirm the published anti-HCV high seropositivity among Egyptian CLD patients and point to an autoimmune processes in CLD. The liver biopsy findings stress the presence of HCV antigen in extra hepatic cells as well as in hepatocytes in CLD. Our data confirm that anti-GOR is commonly present in sera from CLD patients and show that anti-GOR are secreted in saliva. Our results showed that saliva can not be used reliably, instead of serum, for the diagnosis of HCV infection or auto-antibodies related to HCV infection, but can be used as a parameter for the evaluation of CLD activity, when repeated sampling is necessary.

Lack of correlation between sensitivity characteristics of the tests for hepatitis C virus antibodies estimated with serially diluted and natural low-reactive control specimens

Sensitivity characteristics of seven commercial ELISA test systems for the detection of antibodies to hepatitis C virus were assessed using control panels consisting of: (i) serial dilutions of pooled sera highly reactive for anti-HCV; (ii) serial dilutions of RIBA 3.0 HCV SIA positive control; and (iii) natural (non-diluted, non-spiked) sera low-reactive for anti-HCV. "Dilutional sensitivity" values estimated with these two kinds of highly reactive samples did not coincide and were not found to correlate with the proportion of natural low-reactive specimens detected by each test. Thus, laboratories assessing sensitivity of anti-HCV ELISAs should take into consideration the nature and properties of the control material used. Natural low-reactive control specimens are preferable because they adequately reflect the real serological picture of early stage of HCV infection.

HCV core immunodominant region analysis using mouse monoclonal antibodies and human sera: characterization of major epitopes useful for antigen detection

Monoclonal antibodies (MAbs) were generated by immunizing mice with a truncated recombinant protein corresponding to the immunodominant region (residues 1-120) of hepatitis C virus (HCV) nucleocapsid protein. The specific recognition by either human sera or mouse monoclonal antibodies of overlapping peptides spanning the core region 1-120 as well as the comparison with epitopes described earlier allowed the fine mapping of HCV core. Within the region 1-120, the major antigenic domain could be restricted to the first 45 amino acids. Indeed, the peptide S42G (residues 2-45) allowed the detection of an anti-HCV core response by all anticore-positive human sera examined. According to their epitope localization, three groups of mouse MABs could be evidenced that were directed against different regions of core. Group II MAbs recognized a strictly linear epitope (QDVKF, residues 20-24), whereas group I MABs were directed against a conformational epitope mainly located at the amino acid residues (QIVGG, 29-33). The epitope of group III MABs was also conformational (PRGRRQPI, residues 58-65). These three epitopes appeared close but different from the three major human epitopes RKTKRNTN, VYLLPR, and GRTWAQPGYPWPLY (residues 7-17, 34-39, and 73-86, respectively). Group II MAB 7G12A8 and group I MAB 19D9D6 were used in a sandwich ELISA for the capture and the detection, respectively, of viral core antigen in sera of patients with chronic HCV infection. After treatment of sera with triton x 100 in acidic conditions, amounts of viral antigen as low as 20 pg/ml of sera could be detected.

The cellular immune responses induced in the follow-up of interferon-alpha treated patients with chronic hepatitis C may determine the therapy outcome

BACKGROUND/AIMS

To study whether the host's immune response determines viral clearance in chronic hepatitis C, virological markers and antigen-specific T cell reactions were analysed in 30 chronic HCV carriers followed up during interferon-alpha therapy, 11 untreated anti-HCV positive individuals and 10 healthy controls.

METHODS

Proliferative T helper cell responses to recombinant HCV core and non-structural antigens were monitored by 3H-thymidine uptake assay and compared to quantitative viraemia levels and HCV genotypes.

RESULTS

Of the 30 treated patients, six had sustained complete responses (20%), another six were transient therapy responders (20%) and 18 were non-responders (60%). Viral clearance was associated with the HCV genotype 3 and low pretreatment viral load. In a substantial proportion of complete and transient therapy responders, increased NS3-, helicase- and NS4-antigen-specific T cell responses were observed during interferon-alpha therapy. In non-responders and in the later clinical courses of transient therapy responders, core and NS5-specific T cell responses dominated. In addition, 11 untreated anti-HCV antibody positive individuals were studied. Two HCV-RNA negative patients who might have recovered from HCV infection showed strong persistent lymphoproliferative responses to NS3, helicase and NS4 antigens, whereas seven of the nine viraemic patients reacted with HCV core or NS5 antigens.

CONCLUSIONS

Interferon-alpha treatment enhances NS3-, helicase- and NS4-antigen-specific T helper cell responses in patients with viral clearance, whereas viral persistence was associated with increased T cell reactivities against core and NS5 antigens. Immunogenetical, immunological and virological factors that may influence differential T cell induction in chronic hepatitis C are discussed.

Detection of hepatitis C virus core protein circulating within different virus particle populations

Progress in studying pathogenesis and increasing the reliability of hepatitis C diagnosis can be achieved by analysis of different forms of virus particles circulating in blood of both patients and infected persons. Detection of hepatitis C virus (HCV) proteins faces two basic difficulties: low concentration of HCV proteins, and their blocking by antibodies. The aim of this work was to develop a method for the detection of nucleocapsid (core) protein in the plasma of HCV-infected persons using monoclonal antibodies (MABs). Twenty-seven anti-HCV-positive donor plasmas were studied of which 21 contained HCV RNA and 6 were negative. The plasmas were centrifuged for 3 hr at 143,000 g and the antigenic activity of core-protein was studied in the pellets by EIA using four MABs able to recognize four nonoverlapping determinants, two at N-terminus and two at C-terminus of recombinant core (1-150 aa). The determinants detected were present in the natural core protein of at least two genotypes (1b and 3a). Maximal efficiency of recombinant protein detection was achieved with 2 MABs, whereas a combination of 4 MABs was necessary for optimal detection of natural core protein. This is indicative of different conformational structures of natural protein and its gene-engineered analog. The sensitivity of core detection by monoclonal sandwich assay was 1 ng/ml in the pellet or 5 pg/ml after normalization to the initial plasma volume. To dissociate immune complexes, the pellet was treated with 2.5 M KBr after first treating the pellet with the nonionic detergent Tween 80 to remove the virus lipid envelope. Using this treatment protocol, core protein was found in 19 of 21 RNA positive plasmas.

Predictive factors in eradicating hepatitis C virus using a relatively small dose of interferon

Interferon (IFN) can reduce hepatitis C virus load and even eliminate the virus in 30-40% of patients. Several predictive factors for eradication of the virus have been reported and a higher dose of IFN tends to result in elimination of the virus. However, a small dose of IFN sometimes is as effective as a large dose in eradicating the virus. The predictive factors for such a response are not well established. We retrospectively analysed 50 patients with chronic hepatitis C who were treated with relatively small amounts of IFN (equal or less than 252 million units). Eleven patients were responders (elimination of hepatitis C virus (HCV) and normalization of alanine amino transferase (ALT) for at least 6 months), but the remaining 39 were non-responders. Multivariate analysis showed that the pretreatment viral load and total dose of IFN per kilogram of bodyweight were significant predictive factors of response to therapy. We also assessed the amino acid substitutions in the IFN sensitivity determining region (ISDR), NS5A codon 2209-2248, of HCV in serum samples obtained from 31 patients with HCV genotype 1b. The presence of more than one amino acid substitution in the ISDR tended to correlate with HCV genotype 1b elimination. As IFN is expensive and has a number of serious side effects, our study suggests that the optimal dose of IFN may vary from one patient to another and that more stringent criteria should be used to select the optimal dose for therapy.

Hepatitis B and C virus infection prevalence among women in Manila, the Philippines

A seroepidemiological survey of HBsAg, HBeAg, anti-HBs, anti-HBc, anti-HBe and anti-HCV positivities was conducted in 1997 in Manila, The Philippines. Adult women (21 to 59 years of age) were invited to donate peripheral blood for the study, and 50 people volunteered. They were nonsmokers, nonhabitual drinkers, and mostly married; none of them was a professional blood donor. The serum assay showed that all subjects were negative for HBsAg and HBeAg. Overall, a half (50%) of the study subjects were positive for any one of the HBV infection markers (i.e. HBV+). The older group (25 women at 36-59 years of age) showed significantly higher prevalence than the younger group (25 women at 21-35 years of age) of positivity to all three HBV antibody markers and therefore HBV positivity also. None of the study subjects was positive for anti-HCV. Comparison of the present findings with the results reported in the literature for the 1980s suggests that the risk of HBV infection and most probably that of HCV infection also has decreased in this 10-year period in the Philippines.

False-positive reaction between syphilis and hepatitis C infection

There are limited data about false-positive reactions against hepatitis C virus (HCV) in syphilitic patients and false-positive reactions against syphilis in the patients with HCV infection. The aim of this study was to demonstrate the false-positivity of syphilis in patients with HCV infection, the false-positivity of anti-HCV in patients with syphilis and the validity of the serological tests in such patients. Fifty patients with positive anti-HCV, 21 patients with positive VDRL and 50 healthy subjects were studied. Syphilis serology was determined by the Venereal Disease Research Laboratory (VDRL) test and microhemagglutination for T. pallidum (MHA-TP) test. Hepatitis C serology was determined by a second generation ELISA (Ortho Diagnostics) test for HCV antibody, and anti-HCV positive patients were tested for HCV RNA by polymerase chain reaction (PCR). All assays were performed on all subjects. Not only the false-positive VDRL reaction in the patients with HCV infection but also false-positive anti-HCV tests in syphilitic patients have been observed. Four patients with syphilis had positive anti-HCV and negative HCV-RNA, whereas 10% (5 of 50) of patients with hepatitis C infection had positive VDRL and these patients were negative for MHA-TP test. The rates of false-positivity of VDRL and anti-HCV were higher than within the control group (p < 0.05). According to these data, positive anti-HCV in syphilitic patients and positive VDRL in chronic hepatitis C may be false-positive results with regard to the reaginic tests. Therefore, therapeutic measures should not be initiated without confirmation with a treponemal test or PCR. VDRL and HCV-ELISA tests may be interacted with IgM or IgG antibodies. This relationship should be investigated in further studies.

Prevalence of hepatitis A, B, and C markers in school children of a rural area of Crete, Greece

OBJECTIVE

To determine the prevalence of hepatitis A, B, and C markers in children who were attending junior and senior high schools in a high risk area in rural Crete, Greece.

METHODS

Three-hundred and thirty-four children who attended the three junior schools and one senior high school in the Agios Vassilios province of Southern Crete were invited to participate in the study. Three hundred and four of them were tested for hepatitis A, B, and C markers. Hepatitis B (HBV) markers (HBsAg and anti-HBc) as well as hepatitis A (anti-HAV) and hepatitis (anti-HCV) antibodies were tested with commercial enzyme-linked immunosorbent assay kits.

RESULTS

Six of the 304 children (1.97%) were found to be positive for anti-HAV, 1 (0.33%) to HBsAg, 7 (2.30%) to anti-HBc and none were found positive for anti-HCV. No significant differences were seen between the prevalence of anti-HAV antibodies in males (2%) and females (1.95%), and of anti-HBc antibodies in males (3.33%) and females (1.30%).

CONCLUSIONS

The very low prevalence of anti-HAV is obviously due to the improved conditions of hygiene and it raises the question of the possible emergence of this disease at an older age and therefore appropriate preventative strategies should be considered. The low endemicity of hepatitis B in Crete in contrast to other areas of Greece also calls for a vaccination policy probably during adolescence. The absence of hepatitis C markers in the children in contrast to the observed higher prevalence of HCV-infected people in the adult population in the same rural area raises questions regarding possible sources of transmission of hepatitis C during the preceding years.

A clinical, epidemiological and laboratory study on avoiding the risk of transmitting viral hepatitis during vaccinations with the Dermojet protected by an anticontaminant disposable device

Jet injectors may transmit blood-borne infections, such as hepatitis B virus (HBV) and human immunodeficiency virus (HIV). To evaluate the safety of an anticontaminant disposable device which protects the jet injector apparatus, 22,714 healthy subjects were intradermally inoculated (38,162 inoculations) with a variety of vaccines. All the subjects were systematically followed-up clinically and epidemiologically for 6-18 months after inoculation; blood samples from 1619 subjects, before and 60-75 days after inoculation, were examined by enzyme-linked immunosorbent assay (ELISA) for HBV, hepatitis C virus (HCV) and HIV. Before vaccination 212 (13.09%) subjects were positive: 204 positive for HBV markers and eight for the HCV marker. None of the subjects were positive for the anti-HIV marker. During the clinico-epidemiological surveillance and the laboratory investigations mentioned above no clinical viral hepatitis B or C case and no seroconversion to positivity for HBV or HCV markers among the susceptible persons in the group were reported. Considering that in similar situations there is a theoretical risk of transmission as high as 1 per 388 to 1 per 3367 injections and that in our case 38,162 inoculations were performed in 22,714 subjects with the same Dermojet protected by the same type of anticontaminant disposable device, no contamination risk being reported, the conclusion can be reached that jet injectors can be safely used in the medical practice if they are protected by the sterile anticontaminant disposable device.

Acute exacerbations in chronic hepatitis C: a clinicopathological and prognostic study

BACKGROUND/METHODS

To examine the incidence, predisposing factors, clinicopathological characteristics and implications of acute exacerbations in chronic hepatitis C, a consecutive series of 194 biopsy-verified, anti-HCV-positive and hepatitis B surface antigen-negative patients were followed up and studied for the events of acute exacerbations, sustained biochemical resolution and development of cirrhosis.

RESULTS

During a mean period of 6.2 +/- 3.5 (1.0-14.0) years, 151 episodes of acute exacerbations were recorded in 78 patients (40.2%). The estimated annual incidence of acute exacerbations was 11.9%. Fifty-five percent of acute exacerbations were asymptomatic. Histological study of acute exacerbations showed mild to moderate lobular inflammatory activities without bridging hepatic necrosis in all and periportal piecemeal in 23 (42.6%). The clinicopathological features of acute exacerbations in patients with chronic hepatitis C were less severe than those in patients with chronic hepatitis B. The route of infection, sex, age, mode of clinical presentation and the initial histology did not influence the occurrence of acute exacerbations. Only those with alanine aminotransferase > or = 300 U/l at entry tended to develop acute exacerbations more frequently (p < 0.001, odds ratio = 3.6, 95% confidence interval: 1.9-6.5). Acute exacerbations per se did not influence the subsequent development of cirrhosis or sustained biochemical resolution. Cirrhosis developed more frequently in patients with chronic active hepatitis at entry (p < 0.001, odds ratio = 6.5, 95% confidence interval: 2.6-16.0). Compared with baseline HCV-RNA level, HCV-RNA increased in 61% of acute exacerbations but the genotype remained unchanged in 75%.

CONCLUSIONS

These results suggest that acute exacerbations also occur frequently in patients with chronic hepatitis C. They are clinically indolent, histologically less severe and not likely to be followed by sustained remission or development of cirrhosis.

Prevalence of antibodies to hepatitis C virus in hemodialysis patients and renal transplant recipients

This work was carried out to study the prevalence of hepatitis C virus (HCV) infection, its associated risk factors and possible routes of transmission in hemodialysis patients and renal transplant recipients. Ninety five patients and 15 normal controls were included in this study. Patients were classified into 3 groups: Group I (64 hemodialysis patients), Group II (16 renal transplant recipients) and Group III (15 patients with chronic renal insufficiency on conservative treatments). Each individual was subjected to full clinical examination, estimation of serum alanine aminotransferase (ALT), testing for antibodies to hepatitis C virus (anti-HCV), screening for hepatitis B surface antigen (HBsAg), antibodies to hepatitis B surface antigen (anti-HBs) and core antigen (anti-HBc) by modified ELISA technique. Anti-HCV was found in 87.5% of hemodialysis patients, 81.25% of renal transplant patients, 53.3% of the conservative group and in 13.3% of the control group. There was a significant correlation between the presence of anti-HCV and the duration on dialysis in groups I and II (p < 0.05), while no significant correlation was detected between HCV positive cases and the number of units of transfused blood in groups I and II (p > 0.05). Serum ALT was elevated in patients with HCV infection, but there was no significant correlation between the presence of anti-HCV and elevated ALT level among the examined groups of patients (p > 0.05). The prevalence of HCV infection was not correlated with the duration of renal transplantation and the type of immunosuppressive therapy (p > 0.05). Coinfection with HBV and HCV could occur, as previous infection with HBV was demonstrated. Anti-HBc was found in 51.8%, 66.7%, 37.5% of anti-HCV positive patients in groups I, II, II respectively. Anti-HBs was detected in 24.1% and 15.4% of anti-HCV positive in groups I and II. HBsAg was found only in 4.7% of anti-HCV positive hemodialysis.