HCV-infected Donors Research Articles

Distribution of hepatitis C virus in circulating blood components from blood donors

Current nucleic acid tests (NAT) for blood donor screening use plasma as the test sample and, consequently, cannot detect virions bound to blood cells of infected donors. Hepatitis C virus (HCV) RNA and infectious virions have been detected in association with the cellular components of blood of patients with active liver disease; however, studies comparing HCV viral loads in whole blood and plasma have generated contradictory results. The aim of this study was to investigate the distribution of HCV in different compartments of the peripheral blood from HCV-infected blood donors, which may differ from that observed in patients with HCV-associated liver disease. Hepatitis C virus-positive donor specimens were identified by NAT and antibody testing. HCV RNA was extracted from samples of whole blood and their corresponding components (RBC and plasma). Viral RNA was quantified by real-time qRT-PCR. Hepatitis C virus was present in all blood components from infected donors from which RNA could be amplified. For the majority of samples, plasma (34/46) had the highest detectable concentration of HCV RNA, and RBC (37/46) had the lowest. Specimens with negative NAT and positive antibody assays also produced qRT-PCR negative results. These results indicate that including the RBC fraction in the tested sample will not increase assay sensitivity. Although 10% of the specimens had a higher viral load in whole blood, there was no significant overall increase in sensitivity to justify changes in the specimen format. Thus, plasma specimens are well suited for blood donor screening for HCV.

Impact of host responses on control of hepatitis C virus infection in Chinese blood donors

A study was undertaken to explore the molecular mechanisms underlying control of HCV infection in blood donors in China. Factors including clinical information, anti-HCV reactivity (S/CO), IFN-α and IFN-γ, viral loads and genotypes were correlated with 160 index plasma samples at three statuses of 45 recovered, 76 chronic or 39 false positive anti-HCV reactive blood donors. The spontaneous recovery rate was 37.2%. Viral loads of 76 HCV plasmas ranged between 59.8 IU/ml and 2.43 × 10 6 IU/ml (median 3.67 × 10 4 IU/ml). Genotypes 1, 2, 3 and 6 of 63 HCV strains were identified phylogenetically. Recovered donors were significantly younger ( p = 0.002) and had lower level IFN-γ ( p = 0.001) than chronically HCV infected donors. Circulating levels of IFN-α and IFN-γ were higher in those with low viral load and were low in middle or high viral load samples. The ratio of IFN-α to IFN-γ (IFN-α/γ) was significantly positively correlated with viral load ( p = 0.037), and viral load was inversely correlated with IFN-γ in chronic HCV infection regardless of genotype. The study revealed clearly different relationships between IFN-α and IFN-γ in relation to viral load in HCV. A novel measure of IFN-α/γ ratio could be a new approach to evaluate long term outcome of HCV infection.

Long‐term follow‐up among Danish transfusion recipients identified in the national hepatitis C lookback

In 1996, a national lookback study was performed in Denmark identifying 1018 patients exposed to hepatitis C virus (HCV) by transfusion before 1991. The objective of this study was to describe morbidity and mortality during extended follow-up among patients in the Danish HCV lookback cohort alive in 1996. In a retrospective cohort study of 230 patients exposed to HCV by blood transfusion and alive in 1996 we extracted data from national registers and compared these with a matched group of unexposed transfusion recipients. Among 230 HCV-exposed recipients alive in 1996, 124 (53.9%) had chronic hepatitis C, 43 (18.7%) were not infected, and 63 (27.4%) had incomplete HCV data. In 2009, 121 (52.6%) were still alive a median of 21.8 years after transfusion. The mortality rate among the HCV-exposed recipients followed from 1996 was 4.9 per 100 person-years (PY). The incidence of liver cirrhosis and decompensated cirrhosis was 1.0 per 100 PY and 0.4 per 100 PY, respectively; 16.5% had cirrhosis at death. Among HCV-exposed recipients, no difference in all-cause or liver-related mortality was observed between HCV-infected and HCV-uninfected recipients. Further, there was no difference in mortality between HCV-exposed and -unexposed transfusion recipients (mortality rate ratio [MRR], 1.06; 95% confidence interval [CI], 0.96-1.17; p = 0.47), but liver-related mortality was significantly higher among HCV-exposed patients (MRR, 10.0; 95% CI, 7.20-17.7; p < 0.001). Two decades after exposure to blood products from HCV-infected donors, only 121(11.8%) of 1018 recipients remained alive. For HCV-exposed recipients no excess all-cause mortality was observed, but liver-related mortality was significantly increased.

IL28B genetic variants and gender are associated with spontaneous clearance of hepatitis C virus infection

Single nucleotide polymorphisms (SNPs) near the IL28B gene have been shown to be associated with response to treatment for chronic hepatitis C and also with spontaneous clearance of hepatitis C virus (HCV) infection. We analysed the association between IL28B genetic variants and spontaneous clearance of HCV infection in 376 HCV-infected Chinese paid plasma donors. Genotyping of eight SNPs near the IL28B region was performed by the iPLEX system (MassARRAY(®) SNP Genotyping; Sequenom) in all donors, and sequencing was performed on all 80 donors who cleared HCV and on 160 of 296 donors who did not clear HCV to validate the genotypes. Eighty (21.3%) donors spontaneously cleared HCV. Four SNPs were significantly associated with spontaneous HCV clearance: rs8099917 TT (vs GT), rs8105790 TT (vs CT), rs12980275 AA (vs AG) and rs10853728 CC (vs CG or GG) with OR (95% CI) 15.27 (2.07-112.50), 14.88 (2.02-109.72), 7.92 (1.88-33.32) and 2.32 (1.22-4.42) respectively. No association between the other four IL28B SNPs including rs12979860 and spontaneous HCV clearance was found. Women had a higher rate of spontaneous HCV clearance than men [56/213 (26.3%) vs 24/163 (14.6%), P = 0.007], and this was true even after stratification for IL28B genotypes with OR of 1.9-2.2 among those with favourable genotypes. Our results confirmed that IL28B polymorphism is associated with spontaneous clearance of HCV in Chinese subjects, but the SNPs that predict HCV clearance in Chinese subjects were different from those reported in Caucasians. Women were more likely to clear HCV infection regardless of IL28B genotypes.

Intrahepatic inflammatory profiles in HCV/HIV coinfection versus HCV infection (105.10)

Abstract We currently have a poor understanding of the immunopathogenesis of accelerated liver damage in HCV/HIV coinfection. Recent studies suggest that ongoing chronic liver inflammation is responsible for the faster liver damage. We therefore used a real-time PCR-based array to study intraheptic inflammation in the liver biopsy specimens from HCV-infected (n=20), HCV/HIV coinfected (n=8) and healthy (n=8) donors. A total of 84 inflammation-related genes encoding inflammatory cytokines, chemokines and their receptors were analyzed. We found that genes encoding CCL19 and CXCR3-associated chemokines (CXCL9, CXCL10, and CXCL11) were significantly up-regulated in both HCV infection and HCV/HIV coinfection when compared with that of liver biopsies from healthy donors. CXCR3-associated chemokine genes were further up-regulated in HCV/HIV coinfection. Meanwhile, 3 genes (CCL25, CRP, and CXCL2) were significantly down-regulated in HCV infection and HCV/HIV co-infection, and CCL25 was further down-regulated in HCV/HIV coinfection. These data were confirmed by in vitro studies using human hepatocyte cell line Huh7.5. Studies of the molecular mechanisms in regulation of these gene activation showed that LPS and viral proteins played significant roles in the changes of intraheptic inflammatory profiles. Our results suggest that the CXCR3-associated chemokines, particularly CXCL10, may play an important role in the immunopathogenesis of accelerated liver damage in HCV/HIV coinfection.

Absence of occult hepatitis B among blood donors in southern Brazil

BackgroundOccult hepatitis B virus (HBV) infection is characterized by the detection of HBV DNA in serum and/or in liver in the absence of detectable hepatitis B surface antigen (HBsAg). The reported prevalence of occult hepatitis B varies markedly among populations and according to the sensitivity of the HBV DNA assay. The aim of the present study was to describe the prevalence of occult hepatitis B among HCV-infected and non-infected blood donors in Porto Alegre, Southern Brazil, using a highly sensitive real time polymerase chain reaction (PCR) method. MethodologyBetween 1995 and 1997 a sample of 178 blood donors with two positive anti-HCV ELISA tests were consecutively selected as cases, and 356 anti-HCV negative donors were selected as controls. Blood donors were randomly selected from eight blood centers in Porto Alegre, Southern Brazil, representative of the whole blood donor population. Blood samples were kept at 70°C and defrosted for the first time for the analysis of this report. Tests previously performed in the laboratory using the same real time PCR for HBV DNA had sensitivity for detecting as low as 9 copies/mL. Among 158 blood samples from HBsAg-negative blood donors, five were anti-HBc positive, 53 tested positive for anti-HCV and 105 had anti-HCV negative. The samples analysis was performed in duplicate and all blood samples tested negative for HBV DNA. ConclusionThe result reflects a very low prevalence of occult hepatitis B in our setting.

Identification of HCV genotypes in HCV infected blood donors

HCV infection is a leading cause of chronic liver disease, including cirrhosis of the liver. There are at least six major genotypes and more than 50 subtypes of HCV. The prevalence and distribution of HCV genotypes depend on geographical location. The aim of this study was to identify and compare the HCV genotypes in HCV infected blood donors and patients. In this cross-sectional study, 167 serum samples from 103 blood donors and 64 patients with hepatitis C were investigated for HCV genotypes. HCV genotyping was carried out using type-specific primers from the core region of the viral genome. The highest frequency was for genotype 1a, with 53 and 34 (51.5% versus 53.1%) of subjects in blood donors and patients respectively. Genotype 3a and 1b were the other frequent genotypes with 4 and 16 (3.9% versus 25%) and 39 and 10 (37.9% versus 15.6%) subjects, respectively. There was not any statistical significant association between the place of infection of the patients and genotype. The results of this study indicate that the distribution of genotypes in the two populations was similar. The dominant HCV genotypes between blood donors and patients were 1a, 3a and 1b respectively.

Hepatic disorders in chronic kidney disease

Hepatitis B virus (HBV) and hepatitis C virus (HCV) infection are the most common and serious causes of liver damage in patients with chronic kidney disease (CKD). The natural histories of HBV and HCV infections in patients with CKD are not fully understood; however, recent evidence has emphasized the adverse effect of HBV and/or HCV infection on survival in this population. Chronic liver disease is the fourth most important cause of death after renal transplantation. The negative effect of HCV infection on survival among renal transplant recipients has been linked to liver dysfunction and extrahepatic complications, such as chronic glomerulonephritis, post-transplantation diabetes mellitus, chronic allograft nephropathy, and sepsis. The transmission of HCV by solid organ transplantation has been unequivocally demonstrated. Renal transplant recipients who receive kidneys from HCV-positive donors are at increased risk of death. Although several studies have shown that in patients with HCV infection and chronic renal failure renal transplantation is associated with better survival than is dialysis, recent clinical guidelines recommend that kidneys from HCV-infected donors should not be used in HCV-seropositive recipients without detectable HCV viremia. Monotherapy with conventional interferon has been suggested to be a useful treatment for hepatitis C infection in patients on dialysis. Although no evidence suggests that patients with CKD are more prone to suffer from hepatic toxic effects than individuals with normal kidney function, patients with CKD usually receive multiple medications; and drug interactions may, therefore, have a role in the pathogenesis of drug-induced liver disease in this population.

Current Status of Renal Transplantation from Hcv-Positive Donors

Hepatitis C virus (HCV) infection remains frequent among renal transplant (RT) recipients and has a detrimental effect on patient and graft survival. accelerated progression of liver disease due to HCV has been implicated in increased mortality after kidney transplantation but additional outcomes have been related to HCV after RT. all HCV-infected kidney transplant candidates should be considered for liver biopsy before RT. HCV infection should not be considered an absolute contraindication to renal transplantation, although the course of HCV-related liver disease is often progressive. Numerous organ procurement organizations have introduced the policy of accepting kidneys from HCV-positive donors for HCV-positive recipients, but this is still controversial. Single-center experiences have not reported adverse effects on the short-term patient and graft survival, however information from large databases has suggested that RT recipients of HCV-positive donors are independently at risk of mortality even in the modern era of immunosuppression. Renal transplantation should be considered using HCV-seropositive grafts for qualified patients with chronic kidney disease (CKD) stage 5 and HCV infection since good information indicates that the transplantation of kidneys from HCV-infected donors results in improved survival compared to wait-listed and dialysis-dependent candidates. a potential risk related to the use of donor HCV-positive kidneys cannot be excluded, and kidneys from HCV-infected donors should be restricted to recipients with evidence of active viremia at the time of kidney transplantation.

Hepatitis C Virus-Specific Th17 Cells Are Suppressed by Virus-Induced TGF-β

IL-17-secreting T (Th17) cells play a protective role in certain bacterial infections, but they are major mediators of inflammation and are pathogenic in organ-specific autoimmune diseases. However, human Th17 cells appear to be resistant to suppression by CD4(+)CD25(+)FoxP3(+) regulatory T cells, suggesting that they may be regulated by alternative mechanisms. Herein we show that IL-10 and TGF-beta suppressed IL-17 production by anti-CD3-stimulated PBMC from normal individuals. TGF-beta also suppressed IL-17 production by purified CD4(+) T cells, whereas the inhibitory effect of IL-10 on IL-17 production appears to be mediated predominantly by its effect on APC. An examination of patients infected with hepatitis C virus (HCV) demonstrated that Ag-specific Th17 cells are induced during infection and that these cells are regulated by IL-10 and TGF-beta. PBMC from HCV Ab-positive donors secreted IL-17, IFN-gamma, IL-10, and TGF-beta in response to stimulation with the HCV nonstructural protein 4 (NS4). Furthermore, NS4 induced innate TGF-beta and IL-10 expression by monocytes from normal donors and at higher levels from HCV-infected patients. Neutralization of TGF-beta, and to a lesser extent IL-10, significantly enhanced NS4-specific IL-17 and IFN-gamma production by T cells from HCV-infected donors. Our findings suggest that both HCV-specific Th1 and Th17 cells are suppressed by NS4-induced production of the innate anti-inflammatory cytokines IL-10 and TGF-beta. This may represent a novel immune subversion mechanism by the virus to evade host-protective immune responses. Our findings also suggest that TGF-beta and IL-10 play important roles in constraining the function of Th17 cells in general.

Differential reactivity of putative genotype 2 hepatitis C virus F protein between chronic and recovered infections

To date, all studies regarding hepatitis C virus (HCV) F protein have been based on expression in vitro/in vivo of recombinant protein or monoclonal antibodies derived from genotype 1a or 1b sequences, but not from other genotypes. The objective of this study was to prepare a putative genotype 2 recombinant F protein and evaluate its reactivity in plasma from individuals with chronic HCV infection or who had recovered from infection. One genotype 2 strain was selected for F protein (F-2) and core expression in bacterial culture. An ELISA was developed and applied to samples from patients with chronic infection or recovered infection of various genotypes. The anti-F-2 response in 117 samples showed a significantly higher reactivity in chronic than in recovered HCV-infected blood donors (P<0.001), but no difference was found among genotypes. However, the correlation between anti-F and anti-core was more significant in genotypes 1 and 2 than in genotype 3. Anti-F-2 titres were also significantly higher in chronic than in recovered individuals (P<0.0001). Antibody titres to recombinant genotype 2 core protein or to genotype 1 multiple proteins used in commercial anti-HCV assays paralleled the anti-F-2 end-point antibody titre. This study thus demonstrated the antigenicity of genotype 2 HCV F protein, although the exact location of the natural frameshift position remains unknown. The difference in anti-F-2 response between chronic and recovered infection, the cross-reactivity irrespective of genotype and the correlation of antibody response with structural and non-structural antigens suggest that the immune response to F protein is an integral part of the natural HCV infection.

Fiber-modified recombinant adenoviral constructs encoding hepatitis C virus proteins induce potent HCV-specific T cell response

Hepatitis C virus (HCV)-specific cytotoxic T lymphocytes (CTLs) play an important role in HCV clearance. The frequency of HCV-specific T CD8 in peripheral blood of HCV-infected donors is very low and HCV cannot be cultivated for reinfection of antigen presenting cells, making it difficult to detect T CD8 of broad HCV specificities from peripheral blood mononuclear cells (PBMCs). We have developed a recombinant adenoviral system that efficiently reactivates and expands HCV-specific CTLs from PBMCs of HCV-infected donors. Replication-incompetent adenoviruses expressing individual HCV proteins (core and NS3) were produced and PBMCs from HCV-infected donors were transduced with these recombinant adeno-HCV constructs to stimulate HCV-specific CTL populations. T cells expanded from adeno-HCV stimulated cultures were potent producers of HCV-specific IFN-γ and TNF-α and efficiently lysed target cells pulsed with HCV peptides. These constructs could stimulate T CD8 directed towards multiple HCV peptides while preserving the determinant hierarchy. This approach therefore overcomes some of the shortcomings of the selective expansion of CTLs with peptide-based vaccine strategies. These findings provide an effective approach for the expansion of HCV-specific CTLs from PBMCs of HCV-infected patients and have potential for immunotherapeutic/vaccine development.

Open-label trial of therapeutic immunization with oral V-5 Immunitor (V5) vaccine in patients with chronic hepatitis C

We evaluated whether V-5 Immunitor (V5)--tableted therapeutic bivalent vaccine comprising heat-inactivated HCV antigens from pooled blood of HBV- and HCV-infected donors - may produce clinical benefit through induction of oral tolerance and reduction of immune-mediated liver injury. Once daily dose of V5 was administered per os to 10 patients with chronic hepatitis C in an open-label study that lasted 1 month. Every patient who entered the study had elevated liver enzyme levels, which at the end of study have decreased in 100% of analyzed patients. The reduction was highly significant, from 157.7+/-73.4 to 49.9+/-43.8 U/L (P=0.0013) and 147.0+/-79.2 to 58.7+/-56.6 U/L (P=0.0132), for ALT and AST, respectively. The AST/ALT ratio has improved from 0.93 to 1.18 (P=0.00058) indicating the reversion of progression to cirrhosis. None of intent-to-treat patients who were anti-HCV antibody positive at study entry, became negative after 1 month on V5 (P=0.998). All patients, except one, reported complete recuperation from hepatitis C-associated clinical symptoms present at baseline (P=0.0016) with Mantel Haenszel's odds ratio 9.4 (P=0.0021) at 95% confidence interval: 2.7<OR<476.3. No adverse events were observed at any time. The favorable biochemical and clinical responses have been observed in a small number of individuals for a limited time period. Larger scale and longer studies are needed to confirm our preliminary observations suggesting that V5 is safe and effective means for immunotherapy of chronic hepatitis C.

Open Label Trial of Therapeutic Hepatitis B Vaccine V-5 Immunitor (V5)Delivered by Oral Route

We evaluated whether V-5 Immunitor (V5), tableted immunotherapeutic preparation comprising heat- inactivated HBV antigens from pooled blood of HBV- and HCV-infected donors, may produce clinical benefit through induction of oral tolerance and reduction of immune-mediated liver injury. Once daily dose of V5 was administered per os to 10 patients with chronic hepatitis B in an open label study that lasted one month. Every patient who entered the study had elevated liver enzyme levels, which at the end of study have decreased in 100% of analyzed patients. The reduction was highly significant, from 112.4 to 44.4 U/L (P=0.00009) and 118.8 to 46.1 U/L (P=0.0032), for ALT and AST respec- tively. In addition, half of intent-to-treat patients who were HBV surface antigen (HBsAg) positive at study entry, became negative after one month on V5 (P=0.0098). All patients, except one, reported complete recuperation from hepatitis- associated clinical symptoms present at baseline (P=0.0016). No adverse events were observed at any time. Favorable biochemical, virological and clinical responses indicate that V5 is safe and effective means for immunotherapy of chronic hepatitis B. Placebo-controlled, randomized study is required to confirm these findings.

Hepatitis C Virus-Infected Donors in Liver Transplantation

Preliminary findings suggest that hepatitis C virus (HCV)-infected liver transplant recipients receiving livers from HCV-infected donors may have a slower rate of fibrosis progression at 1 year. According to a case-control study presented May 20, 2007 at Digestive Disease Week 2007 in Washington, DC, a trend was seen in survival advantage for those receiving HCV-positive donor grafts compared with standard donor controls. “The use of HCV positive donors may be considered as a first line therapy to increase the available donor pool of organs in those undergoing orthoptic liver transplantation for HCV-related cirrhosis,” say researchers led by Paul Y. Kwo, Associate Professor of Medicine in the Division of Digestive Diseases at Indiana University School of Medicine in Indianapolis. This study utilized a case-control design to compare transplant outcomes for 38 recipients of livers from HCV-infected donors with those for 76 standard, nonextended criteria (ECD) donors (1 case/2 controls). Data were extracted from the transplant center registry, UNOS data, and the original on-site donor data chart. Thirty percent of all donors met non-ECD criteria (standard donors) and were included as potential matches for the case-control study. Each HCV-positive liver donor recipient was matched with 2 standard donor recipients as matched standard donor controls (MSDC) by (1) recipient age ± 10 years; (2) primary diagnosis; (3) cancer stage for those with hepatocellular carcinoma; (4) recipient Model for End-Stage Liver Disease score ± 5; and (5) donor age ± 10 years. Outcomes included graft and patient survival at 3 months, 1 year, and 2 years; perioperative death; and HCV recurrence by 4-month and 1-year fibrosis (F0–F4). The HCV donor and MSDC groups did not differ for recipient or donor demographics or in cold and warm ischemia times. Survival results and fibrosis progression are shown in Table 1. Median follow-up time was 36 months. Kaplan–Meier actuarial survival demonstrated improved graft survival for HCV-infected donors with a trend toward significance (P = .10).Tabled 1Hepatitis C-infected donorMatched standard donor controls (MSDC)n-value*TOTALn = 38n = 7690-day survival Graft37/38 (97.4%)72/76 (94.7%)NS Patient37/38 (97.4%)72/76 (94.7%)NS1-year survival Graft30/31 (96.8%)62/72 (86.1%)NS Patient31/31 (96.8%)63/72 (87.5%)NS2-year survival Graft16/19 (84.2%)49/62 (79.0%)NS Patient17/19 (84.2%)52/62 (83.9%)NSGraft loss within 7 days1/38 (2.6%)1/76 (1.3%)NSMean fibrosis at 4 months (F0–F4)0.680.330.08Mean fibrosis at 12 months (F0–F4).0861.05NSPercent change in fibrosis26%69% Open table in a new tab

Prevalence and screening costs of hepatitis C virus among Ugandan blood donors

Screening donated blood for hepatitis C virus (HCV) is important for HCV prevention and is routinely practiced in North America and Europe. However, in many African countries little is known about HCV prevalence or cost-effectiveness of HCV antibody (anti-HCV) screening. We investigated 2592 plasma specimens collected consecutively from blood donors in central Uganda in 1999. Routine screening by the blood bank included human immunodeficiency virus (HIV), hepatitis B surface antigen (HBsAg), and syphilis. To assess HCV prevalence and cost-effectiveness of testing, specimens were additionally tested for anti-HCV IgG by enzyme immunosorbent assay (EIA). Specimens repeatedly reactive (RR) on EIA were tested with a recombinant immunoblot assay (RIBA). Overall, 107 (4.1%) specimens were HCV EIA RR. Fifteen EIA RR specimens (0.6%, 95% confidence interval = 0.3-0.9%) were RIBA positive and 47 (1.8%) were RIBA indeterminate. Most (80%) RIBA-positive specimens were non-reactive for HIV, HBsAg, and syphilis. RIBA positivity was not associated with donor age, sex, number of donations, HIV, or HBsAg positivity. Costs of screening donors for anti-HCV by using EIA were estimated at US Dollars 782 per potential transfusion-associated HCV infection (exposure to RIBA-positive blood) averted. Current screening tests for other infections are ineffective in removing HCV-positive donations. Testing costs are considerable; cost-effectiveness of identifying HCV-infected donors will be critical in decision making about HCV screening in Uganda.

222 Base Pairs in NS5B Region and the Determination of Hepatitis C Virus Genotype 6

Objective: The present study was performed to genotype hepatitis C virus (HCV) by direct sequencing of a 222-bp nucleotide in the NS5B region and comparing the results with those of direct sequencing in the core region. We investigated a new region for HCV genotyping which gave the best performance to discriminate HCV genotype 6a, the unique genotype found in Southeast Asia. Methods: Plasma samples taken from 57 HCV-infected blood donors were used in this study. RT-PCR products were amplified using primers located in the NS5B region. The 222-bp PCR products were purified and sequenced. The genotype of HCV isolates were obtained by phylogenetic analysis and compared with HCV reference strains stored in the GenBank database. The HCV sequences clustering in the same node were considered to be of the same genotype. Results: Thirty-one, 22 and 4 samples of HCV genotype 3a, 1a and 1b, respectively, were analyzed by this method. Upon comparison with genotyping in the core region, 86 and 14% of the samples yielded concordant and discordant genotype results, respectively. The majority of discordant results (63%; 5 of 8) was observed with HCV genotype 6a which yielded 6a upon core sequencing as opposed to 1a or 3a upon NS5B sequencing. Conclusion: HCV genotype 6a obtained by direct sequencing in the core region could not be unequivocally arrived at by sequencing 222 bp in the NS5B region. Hence, sequencing in the core region is preferable for genotyping our specimens, even though longer PCR products are required as this method enables discrimination between genotype 6a and the remaining genotypes.

Viral Hepatitis

Viral Hepatitis

Risk factors for hepatitis C virus infection among blood donors in northern Thailand.

The epidemiology, virology, and risk factors for hepatitis C virus (HCV) infection among blood donors in northern Thailand have not been extensively evaluated. We did a prospective matched case-control study of blood donors who tested positive for HCV and were confirmed by recombinant immunoblot assay or nucleic acid testing. Infected donors were matched with one to four HCV-uninfected donors for sex, age +/- 5 years, and donation at the same site within 15 days of the HCV-positive donor. Married donors were invited to bring their spouse for HCV testing. Among 166 matched sets, a history of intravenous drug use (IDU), reported by 58 HCV infected donors (35.5%) and 2 HCV-negative donors, was strongly associated with HCV infection (odds ratio [OR], 107.6; 95% confidence interval, 14.8-780.7). In multivariate analysis among donors without a history of IDU, significant risk factors included a history of a blood transfusion (OR, 28.8), immediate family with a history of hepatitis/jaundice (OR, 4.4), six or more lifetime sexual partners (OR, 2.7), and increased frequency of blood donation (OR, 0.9). Six of 45 spouses of HCV-infected donors, and none of 44 spouses of uninfected donors, were HCV positive (p = 0.005). Our data indicate that illicit IDU and a history of transfusion are important risk factors for HCV infection in Thailand. Also, our data suggest there may be some risk of transmission by sex or other close contact between spouses.

Long-term outcome of hepatitis C in children

We appreciate the letter of Bortolotti et al. and the update on their results regarding the prognosis of hepatitis C virus (HCV) infection acquired in childhood, either through transfusion or by the vertical/perinatal route. We agree that hepatitis C is not always an innocuous disease in childhood, and that cirrhosis and extensive fibrosis may occur in some children even in the absence of comorbidities.1, 2 The authors indicate that liver disease may be more severe and progressive in children with liver/kidney microsomal antibody type 1 autoantibodies compared to those without serological markers of autoimmunity.3 In addition, they suggest that maternal coinfection with human immunodeficiency virus and HCV, as well as maternal drug use, both independent risk factors for vertical transmission,4 might have a role in worsening the outcome of HCV infection acquired perinatally. Our data concern the long-term outcome (35 years) of HCV infection in a unique cohort of individuals who acquired HCV through mini blood transfusions derived from an HCV-infected donor.5 All recipients were infected with the same virus genotype (1b), at the same time (shortly after birth) and with the same volume of infectious blood (21–30 mL), and were specifically traced through the clinical files of the hospital in which they were born. None of our HCV-infected individuals were liver/kidney microsomal antibody type 1 -positive and none had comorbid conditions such as hepatitis B virus or human immunodeficiency infection, or alcohol intake (>50 g per day). Moreover, none of the individuals enrolled in this study were aware of having been transfused and infected during the first weeks of life, and only one (who was a drug user) had additional risk factors for HCV infection. Therefore, it would seem that the differences in the outcome of HCV infection acquired in childhood, observed in our and other studies, may be due to differences in the population examined. Taking into account the above findings, one could expect subgroups of children (i.e., those born to HCV-carrier mothers who are coinfected with human immunodeficiency virus and/or are drug users, and those with autoimmune abnormalities) who are at increased risk of developing severe liver disease and even cirrhosis early in life. However, the role of these determinants in heralding a more aggressive outcome in HCV-positive children requires further investigation. Finally, we fully agree with our colleagues that the apparent benign course of HCV infection seen in most children does not imply that treatment should be delayed or even unwarranted in childhood, and that the research of novel, well-tolerated, and effective therapeutic strategies should remain a priority. Alessandro Zanetti*, Maria Antonietta Casiraghi , * Institute of Virology, University of Milan, Milan, Italy, Liver Unit—Department of Medicine, Hospital of Legnano, Milan, Italy.