Generation Recombinant Immunoblot Assay Research Articles

Seroprevalence and risk factors of Hepatitis C Virus in patients and blood donors in Kano, Nigeria

Hepatitis C virus (HCV) is a major cause of chronic liver disease resulting in cirrhosis and hepatocarcinoma. It is believed to be widespread in Africa but its epidemiology is incomplete and is yet to be determined in many areas of the sub-saharan Africa including Nigeria. Using third generation enzyme immuno-assay (EIA-3) and recombinant immunoblot assay (RIBA) technique as confirmatory test, we examined the prevalence of HCV antibodies in 226 blood donors and 226 patients attending Aminu Kano Teaching Hospital (AKTH) in Kano, Nigeria and evaluated the risk factors of HCV transmission in this environment. HCV antibodies were detected in 0.4% and 2.2% blood donors and patients respectively. The overall HCV seroprevalence was 1.3%. There was increased infection acquisition with increasing age; one (16.7%) HCV infection occurred in 25-34 years age group and 5 or 83.3% in subjects > 45 years in age which was significant (P< 0.05). The ratio of infection in male to female was 1:5. Evidence of previous exposure via transfusion was common in HCV seropositive subjects and could be a major risk factor of acquisition in this environment. Adequate screening of blood products in sub- Saharan Africa (Nigeria inclusive) may minimize the risk of HCV transmission and associated health complications.Key words: Hepatitis C virus, seroprevalence, patients, blood donors, risk factors.

Intrafamilial Transmission of Hepatitis C Virus Infection in Iran (Markazi Province)

Objectives: The role of Intrafamilial Hcv transmission is still controversial, the aim of the present study is to determine intrafamilial transmission (Sexual and non sexual contacts) of Hcv in Iran. Methods: In this historical cohort study, we enerolled 270 first degree relatives of hepatits c patients as the exposed group and 270 first degree relative of normal subjects (with negative Hcv) compared as the unexposed group. Positive Hcv and negative Hcv subjects were selected of blood donors reffered to the Regional Blood transfusion organization in Arak from August 2001 to August 2007. First degree relatives were who lived with the index case at least for one year in the same house. Subjects were interviewed using a standard questionnaire acquiring demographic and risk factor information. Then serum samples were obtained from each subject. Antibodies to Hcv were detected employing by commercially available second generation enzyme immunoassay. Positive serum specimens were retested using a second generation recombinant immunoblot assay. Data analysis was carried out with spss for intra-hous hold clustering. We used fisher exact test in order to detect association between the exposure and out come of the study Results: The mean age of exposed group was 27.11± 19.84 years and 38.1% were male. The mean age of unexposed group was 29.38± 16.70 years and 51.9% were male. There was not any significant difference about sex, age, familial relation and candom use between exposed and unexposed subjects. sexual partner subjects formed 24.8% of first degree relatives in the case group. In exposed group, there is no Hcv positive but in unexposed group we had 2 cases of Hcv positive who were intravenous drug abuser. The prevalence of positive Hcv antibody among household contacts of two groups was not significantly different. (P value = 0.25) Conclusion: The results of this study demonstrate that intrafamilial transmission of Hcv is not the significant transmission route and sexual transmission does not seem to play a role in the intrafamilial spread of Hcv infection.

The epidemiology of transfusion‐associated hepatitis C in a children's hospital

Children transfused with blood and blood products before 1992 are at risk for chronic hepatitis C virus (HCV) infection. To determine the prevalence of HCV infection and risks associated with acquisition of HCV, a single-institution lookback study was performed. A total of 5473 infants and children who received transfusions between 1982 and 1992 were identified. A control population of 600 age-, sex-, race- and zip code-matched children who did not receive transfusions with the same exclusions provided background seroprevalence data. Patients were tested for antibodies to HCV, confirmed with second generation recombinant immunoblot assay (RIBA) and when appropriate quantitative and qualitative HCV RNA by reverse transcription polymerase chain reaction (PCR). Viral persistence was assessed by serial PCR determinations for HCV RNA. Of the 5473 eligible patients, 4726 were locatable and 2758 were tested. Forty-three children (1.6%) were persistently anti-HCV enzyme immunoassay (EIA)-positive, confirmed by RIBA; 39 were positive for the presence of HCV RNA. Four cleared their virus as assessed by two negative HCV PCRs 6 months apart. There was a borderline higher number of children with HCV who received fresh whole blood than those who tested HCV-negative. Because HCV infection is generally asymptomatic, children are not identified unless they are specifically tested. We identified, enrolled, tested, and confirmed a new diagnosis of HCV infection in 43 patients. As HCV treatments become increasingly effective, it is important to identify silently infected individuals, particularly when the infection was iatrogenically induced.

Low prevalence of hepatitis C virus infection in Amerindians from Western Venezuela

Previous studies have not found hepatitis C virus (HCV) infection in Amerindians from Western Venezuela. A survey of 254 Bari and Yukpa natives aged 10-60 years (mean +/- SD age = 35 +/- 5.4 years) from four communities, two Bari and two Yukpa, in this area were studied to assess the prevalence of antibodies to HCV (anti-HCV) and HCV RNA among these indigenous populations. Serum samples were examined initially for anti-HCV by a four generation enzyme-linked immunosorbent assay (ELISA). Reactive samples were then tested using a third generation recombinant immunoblot assay (RIBA-3). Viral RNA was investigated in all immunoblot-reactive samples by a nested polymerase chain reaction (PCR) method. Six (2.3%) of 254 natives were positive by ELISA, one (2.2%) of these reactive samples were positive by RIBA, and four (1.5%) were indeterminate. Only two (0.8%) were positive by PCR, corresponding to 1 (2.1%) of 47 inhabitants of a Yukpa community and to 1 (2.2%) of 45 subjects of a Bari community. Iatrogenic is thought to play a role in acquisition of the infection. The findings indicate a HCV focus of low endemicity and are compatible with a low degree of exposures of the natives to the virus. Studies are necessary to assess the risk factors for infection in these Amerindians.

The relationship between lichen planus and hepatitis C in dermatology outpatients in Kerman, Iran

Lichen planus (LP) is classified as a papulosquamous disease. It has been associated with liver disease, particularly hepatitis C virus (HCV) infection, in several studies. Most of these reports, especially the larger series, were conducted in Europe and Japan. We conducted a case-control study in Kerman, Iran to explore the association between LP and HCV. The study included 66 patients with LP (as cases; mean age = 39.7 +/- 15.8 years; 31 female, 35 male) and 140 volunteer blood donors (as controls; mean age = 29.5 +/- 8.4 years; 43 females, 97 males). An enzyme-linked immunosorbent assay (ELISA) was used to determine the presence of anti-HCV antibodies in all subjects in both groups. To confirm positive diagnoses, a second generation recombinant immunoblot assay (RIBA II) test was performed. Lichen planus lesions were most frequently located on the trunk and extremities, and the most common clinical type was generalized LP (48.5%). One of the patients with LP (1.5%) and three of the controls (2.1%) were HCV-Ab positive. No significant difference was observed in HCV-Ab positive between the two groups (OR = 0.7; 95% CI = 0.1-6.9). The findings indicate that an investigation for HCV infection should not necessarily be performed in all patients with LP. It is recommended that further studies should focus on larger groups in other regions of Iran to determine whether testing for HCV infection is necessary in patients with LP.

Sensitivity and specificity of third-generation hepatitis C virus antibody detection assays: an analysis of the literature.

This study assessed the sensitivity and specificity of third-generation serological hepatitis C diagnostic tests from an analysis of the literature. The literature analysis was run using criteria from McMaster University for the assessment of diagnostic tests. The selected studies were grouped according to the type of population at high and low risk for hepatitis C virus (HCV) infection and to the type of reference test. The homogeneity of the sensitivity and the specificity was tested in each group using a Fisher's exact test. Of 132 studies, 10 were selected. When the estimates were homogeneous, summary point estimates and confidence intervals were computed; when the estimates were heterogeneous, subgroup analysis was performed. The sensitivity of third-generation enzyme-linked immunosorbent assay (ELISA3) was estimated at 98.9% (95% CI: 94-100%) in patients with chronic liver disease and at 97.2% (95% CI: 92-99%) in panels of sera. ELISA3 specificity was found at 100% in patients with chronic liver disease. The sensitivity of the third generation recombinant immunoblot assay (RIBA3) was assessed at 78.8% (95% CI: 65-89%) in haemodialysed patients. This analysis provides evidence for the good sensitivity and specificity of ELISA3 assays particularly in high risk patient groups and confirms their use for screening in these populations. Further studies are needed to assess properly RIBA3 in general population and in risk patients.

Hepatitis C virus infection mimicking systemic lupus erythematosus: study of hepatitis C virus infection in a series of 134 Spanish patients with systemic lupus erythematosus.

To determine the prevalence and clinical significance of hepatitis C virus (HCV) infection in patients with systemic lupus erythematosus (SLE). We investigated 134 consecutive SLE patients (121 women and 13 men; mean age 35 years) who fulfilled the 1982 revised criteria for SLE of the American College of Rheumatology. Two hundred consecutive volunteer blood donors were also studied. Serum from all patients and controls was tested for antibodies to HCV (by third generation enzyme-linked immunosorbent assay and confirmed by third generation recombinant immunoblot assay [RIBA-3]). Antibodies to HCV were present in 18 patients with SLE (13%) and in 2 (1%) of the blood donors studied. Among the anti-HCV-positive group, HCV infection was confirmed (by RIBA-3 and polymerase chain reaction) in 15 SLE patients (11%) and in the 2 blood donors (1%) (P < 0.001). We observed a lower frequency of cutaneous SLE features (40% versus 76%; P = 0.01) and positivity for anti-double-stranded DNA (anti-dsDNA) (33% versus 81%; P < 0.001), and a higher frequency of hepatic involvement (93% versus 2%; P < 0.001), low C4 levels (73% versus 39%; P = 0.002), low CH50 levels (73% versus 44%; P = 0.03), and cryoglobulins (60% versus 22%; P = 0.02) in SLE patients with HCV infection compared with SLE patients without infection. The prevalence of HCV infection in SLE patients was higher than in blood donors from the same geographic area. SLE HCV-positive patients showed a lower frequency of cutaneous SLE features and anti-dsDNA antibodies, and a higher prevalence of liver involvement, hypocomplementemia, and cryoglobulinemia. HCV testing should be considered in the diagnosis of SLE, especially in patients who lack the typical cutaneous features of SLE or who have low titers of autoantibodies, cryoglobulinemia, or liver involvement.

Persistence of viremia and the importance of long-term follow-up after acute hepatitis C infection.

The purpose of this investigation was to prospectively characterize acute hepatitis C virus (HCV) infections and to evaluate the hypothesis that the outcome is affected by identifiable clinical or viral factors. One hundred forty-two people with a history of illicit drug use who were HCV antibody-negative in 1988 were followed semiannually through 1996. HCV seroconversion (second generation enzyme immunoassay and recombinant immunoblot assay) was recognized in 43 (30%) of the participants, who were followed up for a median of 72 months. HCV RNA was detected and quantified by polymerase chain reaction in a median of 10 specimens per participant and showed two distinct patterns of viremia: viral clearance was noted in 6 (14%) of the participants, and viral persistence was observed in 37 (86%) of the participants. Subjects with viral clearance were more likely to be white (P =.004), have jaundice (P =.03), and have lower peak viral titer (P =.003). However, the outcome for a given person could not be predicted by clinical features, RNA level, or HCV subtype (as ascertained by analysis of core-E1 complementary DNA sequence). No acute infections were recognized by health care providers. At the time of seroconversion, HCV RNA was detectable in 81% of participants, and recombinant immunoblot assay (RIBA) was positive in 85% of participants. We conclude that approximately 85% of people with acute hepatitis C develop persistent viremia. However, acute infections are uncommonly recognized clinically, underscoring the importance of screening individuals at risk. Long-term follow-up, but no single laboratory test, is necessary to ascertain the outcome and in some cases make the diagnosis of acute HCV infection.

Supplementary anti-hepatitis C virus (HCV) testing with 2nd and 3rd generation recombinant immunoblot assay and matrix applied to enzyme immunoassay positive sera and comparison with HCV-RNA detection

A series of 118 serum samples tested positive in the anti-hepatitis C virus (HCV) 2nd-generation enzyme immunoassay (EIA-2), and indeterminate (93 samples) or negative (25 samples) in the supplementary 2nd-generation recombinant immunoblot assay (RIBA-2). These sera were further evaluated by three additional tests: 3rd-generation RIBA (RIBA-3), MATRIX, and AMPLICOR HCV-PCR. For the 93 RIBA-2 indeterminate serum samples, the results of the immunoassays had a concordance of 69%. Twenty-one and 34 samples remained anti-HCV indeterminate in the RIBA-3 test and the MATRIX, respectively. Among the 25 RIBA-2-negative samples, only seven samples remained anti-HCV negative, while five samples tested anti-HCV positive in both RIBA-3 and MATRIX. The reactivity of the RIBA-3 antigen NS5 was not crucial for the result of any sample. Positive to negative contradictions between the results of MATRIX and RIBA-3 were never observed. Altogether, the MATRIX tested a significantly lower number of samples anti-HCV negative than did the RIBA-3. HCV RNA was detectable in 54/93 RIBA-2 indeterminate and 7/25 RIBA-2 negative samples. High percentages of PCR positive results among RIBA-3-indeterminate and among MATRIX-indeterminate samples indicate an increased possibility of detecting HCV RNA if at least one antigen is reactive. The type of antigen, the pattern of antigen reactivity, or the level of reactivity had no prognostic value in predicting the presence of HCV RNA. Our findings show the necessity of being cautious in the interpretation of RIBA-2-negative results.

Use of Overlapping Synthetic Peptides to Characterize Samples from Blood Donors with Indeterminate Results to Hepatitis C Virus Core Antigen

Abstract Background and Objectives: Despite recent improvements in supplemental assays, isolated reactivity to the hepatitis C virus (HCV) core antigen continues as one of the main problems in the confirmation of anti‐HCV in blood donors. Reactivity against individual peptides from the c22‐3 HCV recombinant antigen has been described as a useful tool for anti‐HCV confirmation and donor counseling in such cases. Materials and Methods: We used a previously described set of overlapping peptides spanning the entire sequence of the c22‐3 antigen to study 87 single serum samples from blood donors with reactivity for c22‐3 antigen alone in second generation recombinant immunoblot assay (RIBA‐2). All of them had been previously studied by RIBA‐3, anti‐HCV E2 EIA and HCV PCR. Results: 66 of the 87 samples studied could be classified as positive or negative for anti‐HCV core using the multipeptide assay and such classification correlated well with the results obtained with RIBA‐3 and the anti‐E2 EIA. However, some discrepancies were found. The epitopes located along the N‐terminal half of the molecule were mainly responsible for the specific antibody recognition but those enclosed within amino acids 1–15 were frequently involved in nonspecific reactivity. Some 38% of samples were considered to have specific antibody to the c22‐3 antigen and a further 9% reacted for both anti‐E2 and single core peptides that were often involved in specific antibody recognision. Conclusion: Testing of blood donor samples indeterminate to the HCV c22‐3 antigen for reactivity against individual core peptides can confirm the presence of specific antibody and recognize nonspecific reactivity with certain cross‐reacting epitopes. Third generation supplemental tests have reduced such false reactivity, but confirmation of samples with anticore alone is still necessary. Single reactivity to the HCV core antigen is likely to reflect prior exposure to the virus, but rarely active infection, either acute or chronic.

Vertical transmission of hepatitis C virus: an epidemiological study on 2,980 pregnant women in Italy.

The risk of mother-to-infant transmission of hepatitis C virus (HCV) varies according to the population studied and the tests used. Aim of the current study was to investigate HCV vertical transmission rate in children born to 30 HCV positive/HIV negative pregnant women in Italy. We investigated the potential vertical transmission of HCV by identifying HCV antibody seropositive pregnant women, by analyzing HCV-RNA in the peripheral blood using PCR and by prospectively following their offspring until 24 months of age. During the third trimester, 2,980 consecutive pregnant women were examined for anti-HCV antibodies by a second generation Enzyme-Linked Immunosorbent Assay (EIA2) and re-assayed by a second generation Recombinant Immunoblot Assay (RIBA2). A total of 32 mothers (1.07%) were positive for EIA2 test; 30 out of 32 had a reactive confirmatory RIBA2 test for HCV. All anti-HCV positive mothers were negative for HIV. These 30 mothers and their 30 babies formed the study cohort. Of the 30 anti-HCV positive mothers, 10 were also positive for serum HCV-RNA by PCR. All the babies born to the 30 anti-HCV positive mothers were initially negative for HCV-RNA (cord blood specimens), but three babies became positive at three months of age and remained positive thereafter. These babies had been born to 3 of the 10 mothers with viremia during the third trimester of pregnancy. These results suggest that HCV vertical transmission is possible in 10% of anti-HCV positives and in about 33% of the HCV-RNA seropositive mothers.

Mother-to-infant transmission of hepatitis C virus: a prospective study.

To investigate the risk of mother-to-infant transmission of hepatitis C virus (HCV) and the natural course of HCV-infected infants, we prospectively studied 31 offspring of pregnant women who were anti-HCV positive and anti-HIV negative. Sera were serially tested for anti-HCV by the second-generation ELISA-test (ELISA-2) and for HCV-RNA by the polymerase chain reaction procedure. The mean period of follow up was 19 months (range 6-41 months). The presence of HCV-RNA in the mothers was associated with a high titre of anti-HCV by ELISA-2 or a positivity of the second generation recombinant immunoblot assay. At birth, 26 babies were positive for anti-HCV. Passively transferred maternal antibodies became undetectable within 2-15 months. HCV-RNA was detected in only 3 infants (9.7%) within 1-4 weeks after birth and persisted thereafter. The genotype of HCV-RNA in each of the infants was consistent with that of their mother. These 3 showed chronic transaminase elevation during the follow up that started at 1-2 months of age, although they revealed no clinical symptoms. Reelevation of anti-HCV titre was observed in the HCV-infected infants within 10 months of age, suggesting an endogenous production of anti-HCV. The mean titre of HCV-RNA in three mothers of infected infants was higher than that in the mothers of uninfected infants (10(5.3 +/- 0.3) vs 10(4.4 +/- 0.2)/ml). Our findings indicate that HCV was most likely to have been transmitted from mothers to infants at the time of delivery and that it was capable of evoking the chronic carrier state.

Psoriasis and hepatitis C virus.

We have analyzed 8 patients (6 men and 2 women, aged 52 to 70 years) with psoriasis associated with hepatitis C virus (HCV) infection among 79 psoriatic patients. Psoriasis preceded in 6 cases. One patient had generalized pustular psoriasis (GPP), and the others had psoriasis vulgaris (PV). The psoriasis area and severity index (PASI) score ranged from 2.7 to 32.4. Two of the patients were treated with interferon-gamma. Anti-HCV antibodies were detected in all cases by second generation enzyme-linked immunosorbent and recombinant immunoblot assay. HCV messenger RNA was demonstrated by reverse transcriptase polymerase chain reaction in the tissue sections of the lesions of 1 of the patients with PV and the patient with GPP, providing evidence for active viral replication in the skin lesion. HCV-related chronic active hepatitis might cause several immunological abnormalities. It is suggested that this infection might be one of the triggering factors of psoriasis.

High hepatitis C viraemia and impaired antibody response in patients coinfected with HIV

To compare hepatitis C virus (HCV) load in patients infected with HCV alone and those coinfected with HIV, and to evaluate the antibody response to HCV in the case of HIV infection. Patients coinfected with both HCV and HIV have been shown to develop hepatic changes more rapidly, which may be due to an interaction between HCV and HIV. In a prospective study, serum samples were taken from 150 patients. Using reverse transcription followed by polymerase chain reaction and the branched DNA assay, we detected HCV RNA in 75 patients coinfected with HIV and HCV and in 75 patients infected with HCV alone. The HIV RNA was also quantified by the branched DNA assay and the p24 antigenaemia was determined by enzyme-linked immunosorbent assay. The immune response to HCV was studied in the 150 patients by the use of third generation recombinant immunoblot assay (RIBA). Although a comparable number of patients had detectable HCV viraemia in both groups, HCV RNA was quantifiable in 79% of HIV-positive patients and in only 43% of HIV-negative patients (P < 10(-5)), and the mean HCV RNA level was much higher in the HIV-positive group than in the HIV-negative group (P < 10(-7)). The quantity of HCV RNA did not correlate with the CD4 count, p24 antigenaemia or HIV RNA level. The analysis of RIBA showed 14.7% indeterminate or negative results in the HIV-positive group and only 4% indeterminate results in the HIV-negative group. HIV-positive patients had reactivity to less antigen bands than HIV-negative patients (P < 10(-3)), and they had a weaker reactivity to c100, c33c and NS5 antigen bands than HIV-negative patients. Our results show that in the case of HIV infection, the HCV RNA levels are strongly increased, but HCV load is not linked to the immunosuppression induced by HIV; therefore, the present data do not support the hypothesis of a direct interaction between HIV and HCV.

Heptitis B and C virus infection in HBsAg-negative alcoholics without i.v. drug abuse or previous blood transfusions

The presence of low level hepatitis B virus (HBV) and hepatitis C virus (HCV) infections was assessed in serum from 67 hepatitis B surface antigen (HBsAg) negative alcoholics from France without previous blood transfusions and/or i.v. drug abuse. It was found that 19 67 (28%) of this alcoholic population had past exposure to HBV as shown by the presence of antibodies to the surface (anti-HBs), core (anti-HBc) and e (anti-HBe) antigens. Two patients (3%) had low level circulating encapsidated HBV as determined by the highly sensitive capture PCR technique. Previous exposure to HCV was assessed by three serological tests: the first generation ELISA (C-100-3), a second generation recombinant immunoblot assay (RIBA II) and a radioimmunoassay based on highly conserved HCV core peptide sequences; 7 67 (10.5%) were found to be reactive in at least two serological tests. Among 64 serum samples available for RNA PCR testing, 6 were found to be HCV RNA positive (9.4%). Taken together, 8 67 (13%) of this alcoholic population were positive for HCV by RNA PCR and/or at least two serological tests. We conclude, that even in the absence of known risk factors and HBsAg negativity, patients with alcoholic liver disease have a significantly higher prevalence of markers of past or ongoing HBV or HCV infection than healthy individuals.

Comparison of Three Different Tests for Assessment of Hepatitis C Virus in Dialysis Patients

Objective To evaluate the relationship between hepatitis C virus antibodies (HCV-Ab) and viremia and to compare the prevalence of HCV-Ab and HCV viremia in hemodialysis (HD) and continuous ambulatory peritoneal dialysis (CAPD) patients. Design Cross-sectional study. Setting Dialysis unit of a nephrology division in a public university hospital. Patients All dialysis patients who came for routine clinic visits during the study period. None denied informed consent. Forty-eight patients on HD and 79 on CAPD were examined. Intervention Blood samples were tested by second generation enzyme-Iinked immunosorbent assay (ELISA II) and recombinant immunoblot assay (RIBA II) to look for HCV-Ab and by the polymerase chain reaction (PCR) to look for HCV viremia. Results ELISA II was positive in 52% of HD patients and in 14% of CAPD patients. RIBA II was positive in 48% of HD patients and in 11% of CAPD patients. HCV viremia was positive by PCR in 41.6% of HD patients and in 12% of CAPD patients. Two of these PCR-positive patients did not show HCV-Ab by ELISA II and RIBA II. The sensitivity and specificity of ELISA II were 93% and 92%, the sensitivity and specificity of RIBA II were 86% and 94%. Conclusions Our data confirm a higher prevalence of HCV viremia in HD than in CAPD patients. The absence of Ab against virus C in 2 patients positive with PCR might be due to recent HCV infection or to weak virus replication or to a poor immune response.

Long interval between HCV infection and development of hepatocellular carcinoma

A high prevalence of HCV infection has been reported in patients with hepatocellular carcinoma. The progression from acute transfusion-associated hepatitis to hepatic cirrhosis and hepatocellular carcinoma has been suggested in several studies to be very long. We have investigated the prevalence of anti-HCV and the interval between HCV infection and hepatocellular carcinoma among 191 consecutive patients with cirrhosis and liver-cell carcinoma. Serum samples from 191 patients with cirrhosis and hepatocellular carcinoma, consecutively diagnosed in our hospital between 1988 and 1993, were tested for serological markers of HBV and HCV infection. One hundred and forty-eight patients (77.5%; 95% confidence interval (c.i): 76% to 80%) were anti-HCV positive by 2nd generation enzyme immunoassay (confirmed by 2nd generation recombinant immunoblot assay) and 152 patients (79.5%; 95% c.i: 76% to 80%) were anti-HCV positive by 3rd generation enzyme immunoassay, while only 14 (7.4%; 95% c.i: 5% to 10%) were HBsAg positive. Of the 29 anti-HCV positive patients with previous transfusion, the interval between the date of blood transfusion and the diagnosis of hepatic cirrhosis was 24 +/- 12.5 years and that of hepatocellular carcinoma was 26.8 +/- 12.4 years. These results confirm the high prevalence of HCV infection in patients with hepatocellular carcinoma and the slow sequential progression from HCV infection through cirrhosis and hepatocellular carcinoma.

Hepatitis C infection and viremia in Dutch Hemophilia patients

Serum samples from 316 patients visiting the Dutch National Hemophilia Center were collected from 1979 to 1993 and stored at -30 degrees C. Patients were placed into three different groups: 1) patients ever treated with large pool non-hepatitis C virus (HCV)-safe concentrate (n = 179); 2) patients treated with cryoprecipitate (n = 125); and 3) patients treated exclusively with HCV-save concentrate (n = 12). In order to examine the prevalence of HCV infection in the different treatment groups serum samples were tested retrospectively for anti-HCV antibody using second generation enzyme-linked immunosorbent assay (ELISA) and recombinant immunoblot assay (RIBA-2). Significant differences in the prevalence of HCV infection were found between these 3 groups (group 1: 99%, group 2: 66%, group 3: 0%). The safety of currently administered clotting products is demonstrated in 57 patients who remained without HCV markers between 1989 and 1993. To examine the natural course of HCV infection fresh-frozen plasma samples were obtained recently from a subgroup of 277 hemophilia patients for HCV-RNA detection by a well-validated cDNA-PCR assay. In contrast to other reports, no evidence was found for seronegative HCV carriers. None of 52 patients without anti-HCV had detectable HCV-RNA. Of 225 patients with anti-HCV, 182 (81%) were HCV-RNA positive. None of 39 anti-HCV positive patients with a negative HCV-RNA reaction had serum alanine aminotransferase (ALT) levels above 50 U/l, whereas 44% of HCV-RNA positive patients had persistently elevated ATL levels above 50 U/l.(ABSTRACT TRUNCATED AT 250 WORDS)

HCV antibodies in Hungarian blood donations. Experiences collected by ELISA tests, immunoblot assays and polymerase chain reaction and protocols for donor management.

Routine screening of Hungarian blood donors for anti-HCV commenced in the second half of 1992. Before this, five available anti-HCV ELISA kits were compared in pilot studies. In the first series, 831 random donor samples were tested by one of the tests and the 12 (1.4%) reactives found were retested by the other four. Six of the reactives were positive in all ELISA. In the second series, 325 samples from donors with elevated transaminase levels were tested by all five kits. Forty-four were found to be reactive by one or more of the tests and 32 (10%) were positive in all five assays. Samples concordantly reactive in the ELISA were positive in second or third generation recombinant immunoblot assay (RIBA 2 or RIBA 3); those that gave discordant results were indeterminate or negative. Eleven concordantly reactive samples from the second series were HCV RNA positive by polymerase chain reaction (PCR). In the first period of screening with Abbott ELISA 2 a repeat-reactivity rate of 0.98% was observed in 171,106 samples tested. Reactives were retested for supplementary testing by Wellcozyme anti-HCV. Donors reactive in both tests and strongly reactive (ELISA ratio (ER) = optical density/cut off > or = 2.5) in either of them were permanently deferred. Those negative in the supplementary ELISA or weakly reactive (1.0 < or = ER < 2.5) in both tests were subjected to RIBA 2. On the basis of RIBA, positive donors were permanently deferred, indeterminates were excluded for 1 year and negatives were readmitted. In 1992, 1,347 supplementary tests were completed; 824 (61%) of the respective donors were permanently deferred, 218 (16%) were deferred for 1 year and 305 (23%) were readmitted.

Hepatitis C Virus Infection in Children Treated for Acute Lymphoblastic Leukemia

We studied 102 consecutive subjects after their completion of acute lymphoblastic leukemia (ALL)-directed chemotherapy, for evidence of hepatitis C virus (HCV) infection by enzyme immunoassay 2 and 3, second generation recombinant immunoblot assay and reverse transcription-polymerase chain reaction (PCR) for detection of circulating HCV-RNA. Forty-four patients (43%) had evidence of exposure to HCV; 30 of these were anti-HCV+. Of the 23 patients who were positive for both anti-HCV and HCV-RNA, 16 (69%) had a moderate increase in serum alanine aminotransferase (ALT) activity without clinical signs of liver disease. Fourteen patients were seronegative despite the presence of HCV-RNA in the serum. The proportion of different HCV genotypes was not significantly different from other anti-HCV+ patient groups. Although half of the patients with genotype III had normal ALT value, patients with normal ALT levels were represented in all genotype groups. Our study documents the prevalence of HCV infection in childhood ALL survivors, which is responsible for the majority of cases of non-B chronic liver disease in these patients. Whereas serologic screening identifies over 70% of patients with ongoing HCV infection, real HCV infection may be present even in the absence of a detectable humoral immune response to the virus. Based on this observation, determination of HCV-RNA by PCR should be recommended in patients in prolonged remission even if they test negative on serological assay. Normal ALT levels do not exclude the presence of HCV infection because the values were repeatedly normal in over half of our viremic patients.