HCV Infection Alters Salivary Gland Histology and Saliva Composition.

Hepatitis C virus (HCV) infection is the most common blood-borne chronic infection in the United States. Chronic lymphocytic sialadenitis and sicca syndrome have been reported in chronic HCV infection. Up to 55% of these patients may have xerostomia; the mechanisms of the xerostomia and salivary gland (SG) hypofunction remain controversial. The objectives of this project are to establish if xerostomia associates with SG and HCV infection and to characterize the structural changes in SG and saliva composition. Eighteen HCV-infected patients with xerostomia were evaluated for SG dysfunction; 6 of these patients (patients 1-6) were further evaluated for SG histopathological changes and changes in saliva composition. The techniques used include clinical and laboratory assessment, SG ultrasonography, histological evaluation, sialochemical and proteomics analysis, and RNA in situ hybridization. All the HCV patients had low saliva flow, chronic sialadenitis, and SG fibrosis and lacked Sjögren syndrome (SS) characteristic autoantibodies. Further evaluation of a subgroup of 6 HCV patients (patients 1-6) demonstrated diffuse lymphocytic infiltrates that are predominantly CD8+ T cells with a significant increase in the number of inflammatory cells. Alcian Blue/periodic acid-Schiff staining showed significant changes in the ratio and intensity of the acinar secretory units of the HCV patients' minor SG. The submandibular glands showed significant ultrasonographic abnormalities in the parenchyma relative to the parotid glands. Significant changes were also observed in the concentration of sodium and mucin 5b. Although no significant correlation was observed between the lymphocytic infiltrates and the years of HCV chronic infection, a positive correlation was observed between HCV RNA-positive epithelial cells and the years of HCV infection. Consistent with the low saliva flow and xerostomia, patients showed changes in several markers of SG acinar and ductal function. Changes in the composition of the saliva suggest that HCV infection can cause xerostomia by mechanisms distinct from SS.

The natural history of acute hepatitis C: clinical presentation, laboratory findings and treatment outcomes.

BACKGROUND: Acute hepatitis C has variable modes of presentation and frequently results in chronic infection. Its optimal management has yet to be defined. AIM: To establish natural history and complications of treatment of acute hepatitis C. METHODS: Data from all patients presenting with acute hepatitis C to the National Institutes of Health between 1994 and 2007 were reviewed. RESULTS: Twenty-five patients were identified. Symptoms were reported by 80% and jaundice by 40%. Aminotransferase levels and hepatitis C virus (HCV) RNA levels fluctuated greatly; 18% of patients were intermittently negative for HCV RNA. Five patients recovered spontaneously whereas 20 developed chronicity or received interferon-based therapy during the acute phase. Among 15 patients treated during the acute phase with peginterferon with or without ribavirin for 24 weeks, all became HCV RNA negative within 4-8 weeks, and all except two (HIV-positive) achieved a sustained virological response. Side effects (particularly psychiatric) were common and limited treatment in 30%. CONCLUSIONS: Among 25 patients with acute HCV infection, fluctuating illness was common and spontaneous recovery occurred in only 20%. Anti-viral treatment with a 24-week course of peginterferon and ribavirin was highly effective, but marked by frequent and severe side effects.

SEN virus infection in patients with hepatocellular carcinoma.

Although most cases of hepatocellular carcinoma (HCC) are associated with either the hepatitis B or C viruses (HBV, HCV), about 10-20% of HCCs occur in patients with chronic hepatitis that is aetiologically undefined. The aim of the present study was to determine the prevalence of the transfusion-transmitted SEN virus (SEN-V) in patients with HCC, including those patients who do not otherwise appear to be infected with HBV or HCV. Fragments of SEN-V subtypes D and H were amplified separately by PCR from the sera of 50 patients with HCC (31 from Canada and 19 from Japan) as well as from HCC and adjacent nontumourous liver tissues from eight of the Canadian patients. SEN-V DNA was found in the serum of 10 of 31 (32%) Canadian patients and eight of 19 (42%) Japanese patients [overall, 18 of 50 (36%) HCC patients]. SEN-V DNA was detected in the serum of 10 of 23 (43%) HCC patients with antibody to HCV (anti-HCV), six of 11 (55%) with hepatitis B surface antigen (HBsAg), and two of 16 (12%) without detectable anti-HCV or HBsAg. Twenty-three HCC patients in this study had 'silent HBV,' characterized by the detection of HBV DNA in the absence of HBsAg; eight of these (35%) also had SEN-V infections. SEN-V DNA was detected in HCC patients most typically in those with coexistent HBV or HCV infection. SEN-V was found in only one of seven HCC patients without HBV (without HBsAg or HBV DNA) or HCV and thus does not appear to be an important cause of 'cryptogenic' HCC.

DNA immunization encoding the secreted nonstructural protein 3 (NS3) of hepatitis C virus and enhancing the Th1 type immune response.

To induce a sustained and specific cellular immune response to hepatitis C virus (HCV), DNA immunization of mice was performed using plasmids containing the HCV nonstructural gene 3 (HCV/NS3). Plasmids were constructed such that the NS3 gene was expressed in a secreted form, a nonsecreted form or as a membrane-bound antigen. The plasmid encoding the secreted antigen induced the strongest humoral and cellular immunity and favoured the T-helper type 1 (Th1) pathway as shown by cytokine profiles and switching of antibody subclasses. Our study indicates that DNA immunization with a secreted form of HCV/NS3 is an effective means of inducing primary Th1 immune responses in the murine model.

Association between SEN virus infection and hepatitis C in Japan.

There is a strong association between 2 SEN virus (SENV) variants (SENV-D and SENV-H) and transfusion-associated non-A-E hepatitis. In total, 200 subjects from a Japanese region where hepatitis C virus (HCV) is highly endemic and 194 persons from a contiguous area where HCV is not endemic were tested for SENV-D and SENV-H DNA by polymerase chain reaction. SENV DNA was detected equally in subjects from each area (56% prevalence in the area of high endemicity vs. 61% in the nonendemic area). Age-specific prevalence of SENV was similar to that of TT virus, with equal distribution at all ages in both areas; HCV was predominant in the elderly population. Alanine aminotransferase levels were significantly associated with HCV viremia but not with SENV viremia. SENV is a common infection that appears to have transmission routes and age-related prevalence that are distinct from those of HCV. No evidence was found that SENV caused hepatitis or worsened the course of hepatitis C.

Dynamics of SEN virus infection among injection drug users.

SEN virus (SENV) is a recently discovered group of DNA viruses whose members (SENV-D and SENV-H) are linked to posttransfusion hepatitis. Of 397 injection drug users (IDUs) in Baltimore, Maryland, SENV-D infection was detected by polymerase chain reaction in serum samples from 130 (32.7%) and SENV-H infection in 149 (37.5%). Of 41 IDUs in whom SENV-D DNA was initially detected, retesting for viral persistence a median of 9.3 years later detected SENV-D in 25 (61.0%), whereas SENV-H was detected on retesting in only 14 (26.9%) of 52 IDUs in whom the virus was originally found. Reinfection was apparent (>5% nucleotide difference) in 77.8% of IDUs who repeatedly tested positive for SENV-D DNA and in 55.6% of those who repeatedly tested positive for SENV-H DNA. Among Baltimore IDUs, SENV-D and SENV-H infections are common and dynamic, including both viral clearance and reinfection. The clinical significance of SENV infection in this setting remains unknown.

Emerging infectious disease issues in blood safety.

Improvements in donor screening and testing and viral inactivation of plasma derivatives together have resulted in substantial declines in transfusion-transmitted infections over the last two decades. Most recently, nucleic acid testing techniques have been developed to screen blood and plasma donations for evidence of very recent viral infections that could be missed by conventional serologic tests. Nonetheless, the blood supply remains vulnerable to new and reemerging infections. In recent years, numerous infectious agents found worldwide have been identified as potential threats to the blood supply. Several newly discovered hepatitis viruses and agents of transmissible spongiform encephalopathies present unique challenges in assessing possible risks they may pose to the safety of blood and plasma products.

Stability of HCV-RNA level and its lack of correlation with disease severity in asymptomatic chronic hepatitis C virus carriers.

This study examines the relationship between HCV-RNA levels and disease severity in 60 individuals with chronic hepatitis C virus infection. HCV-RNA levels were quantified by the branched DNA (bDNA) assay in 445 samples (median: eight samples per patient) obtained over a median of 40.4 months (95% confidence interval (CI): 37.0-42.5). The median log HCV-RNA level was 6.77 (95% CI: 6.62-6.92) molecular equivalents/mL (MEQ/mL). The median log range of HCV-RNA levels in individual patients over the course of the study was 0.89 (95% CI: 0.69-1.16). HCV-RNA level varied over time by less than one log in 62% of patients, by 1-1.5 logs in 22% and by greater than 1.5 logs in only 17%. Univariate analysis, revealed an inverse association between HCV-RNA levels and ALT levels (P=0.037). Univariate and logistic regression analysis showed no significant association between HCV-RNA levels and either the degree of inflammation or fibrosis. In contrast, there was a significant positive association between alanine aminotransferase (ALT) levels and histological activity especially in individuals with ALTs> 100 IU/L. Hence, HCV-RNA levels: (i) almost always fell within the dynamic range of the bDNA assay; (ii) were stable in asymptomatic chronically infected patients, with only a small proportion of patients exceeding a range of 1.5 logs; (iii) did not correlate with either the extent of inflammation or degree of fibrosis. In contrast, there was a strong association between ALT level and the histological severity of liver disease.

The presence of a newly identified infectious agent (SEN virus) in patients with liver diseases and in blood donors in Japan.

The existence of the newly discovered SEN virus (SENV) was investigated in 379 Japanese patients with liver diseases and in 277 blood donors, to determine whether SENV is associated with non-A-E hepatitis. SENV DNA was detected by seminested polymerase chain reaction, with primers directed to 2 SENV strains: SENV-H and SENV-D. SENV was detected in 7 (32%) of 22 patients with fulminant hepatitis, in 15 (17%) of 86 patients with acute hepatitis, in 38 (27%) of 139 patients with chronic hepatitis, in 29 (31%) of 93 patients with liver cirrhosis, in 5 (33%) of 15 patients with autoimmune hepatitis, in 11 (46%) of 24 patients with primary biliary cirrhosis, and in 27 blood donors (10%). Infection occurred more frequently in patients with liver diseases than in blood donors; however, there were no significant differences in SENV-positive rates between patients with non-A-C hepatitis and those with acute or chronic hepatitis due to known hepatitis virus or nonviral liver disease. This study did not suggest SENV as a possible causative agent of non-A-C hepatitis.

SEN virus infection and its relationship to transfusion-associated hepatitis.

SEN virus (SEN-V) is a recently identified single-stranded, circular DNA virus. Two SEN-V variants (SENV-D and SENV-H) were assayed by polymerase chain reaction (PCR) to investigate their role in the causation of transfusion-associated non-A to E hepatitis. The incidence of SEN-V infection after transfusion was 30% (86 of 286) compared with 3% (3 of 97) among nontransfused controls (P < .001). Transfusion risk increased with the number of units transfused (P < .0001) and donor-recipient linkage for SEN-V was shown by sequence homology. The prevalence of SEN-V in 436 volunteer donors was 1.8%. Among patients with transfusion-associated non-A to E hepatitis, 11 of 12 (92%) were infected with SEN-V at the time of transfusion compared with 55 of 225 (24%) identically followed recipients who did not develop hepatitis (P < .001). No effect of SEN-V on the severity or persistence of coexistent hepatitis C virus (HCV) infection was observed. In 31 infected recipients, SEN-V persisted for greater than 1 year in 45% and for up to 12 years in 13%. SEN-V-specific RNA (a possible replicative intermediate) was recovered from liver tissue. In summary, SENV-D and -H were present in nearly 2% of US donors, and were unequivocally transmitted by transfusion and frequently persisted. The strong association of SEN-V with transfusion-associated non-A to E hepatitis compared with controls raises the possibility, but does not establish that SEN-V might be a causative agent of posttransfusion hepatitis. The vast majority of SEN-V-infected recipients did not develop hepatitis.

Long-term mortality and morbidity of transfusion-associated non-A, non-B, and type C hepatitis: A National Heart, Lung, and Blood Institute collaborative study.

Persons with non-A, non-B hepatitis (cases) identified in 5 transfusion studies in the early 1970s have been followed ever since and compared for outcome with matched, transfused, non-hepatitis controls from the same studies. Previously, we reported no difference in all-cause mortality but slightly increased liver-related mortality between these cohorts after 18 years follow-up. We now present mortality and morbidity data after approximately 25 years of follow-up, restricted to the 3 studies with archived original sera. All-cause mortality was 67% among 222 hepatitis C-related cases and 65% among 377 controls (P = NS). Liver-related mortality was 4.1% and 1.3%, respectively (P =.05). Of 129 living persons with previously diagnosed transfusion-associated hepatitis (TAH), 90 (70%) had proven TAH-C, and 39 (30%), non-A-G hepatitis. Follow-up of the 90 TAH-C cases revealed viremia with chronic hepatitis in 38%, viremia without chronic hepatitis in 39%, anti-HCV without viremia in 17%, and no residual HCV markers in 7%. Thirty-five percent of 20 TAH-C patients biopsied for biochemically defined chronic hepatitis displayed cirrhosis, representing 17% of all those originally HCV-infected. Clinically evident liver disease was observed in 86% with cirrhosis but in only 23% with chronic hepatitis alone. Thirty percent of non-A, non-B hepatitis cases were unrelated to hepatitis viruses A,B,C, and G, suggesting another unidentified agent. In conclusion, all-cause mortality approximately 25 years after acute TAH-C is high but is no different between cases and controls. Liver-related mortality attributable to chronic hepatitis C, though low (<3%), is significantly higher among the cases. Among living patients originally HCV-infected, 23% have spontaneously lost HCV RNA.

The relationship of acute transfusion-associated hepatitis to the development of cirrhosis in the presence of alcohol abuse.

BACKGROUND: Although concomitant alcoholism is widely believed to enhance liver disease progression in persons with hepatitis C virus (HCV) infection, this relationship has not been well quantified. OBJECTIVE: To quantify the relationship of transfusion-associated HCV infection and history of heavy alcohol abuse to development of cirrhosis. DESIGN: Retrospective cohort study. SETTING: Liver clinics in university and government hospitals. PATIENTS: Extended follow-up of 1030 patients in prospective investigations of transfusion-associated viral hepatitis conducted in the United States between 1968 and 1980. MEASUREMENTS: Development of cirrhosis and history of heavy alcohol abuse were determined from review of interviews with patients or their proxies, medical records, death certificates, and autopsy and biopsy reports. Logistic regression was used to estimate the risk for cirrhosis associated with transfusion-associated HCV infection and history of heavy alcohol abuse. RESULTS: The absolute risk for cirrhosis was 17% among patients with transfusion-associated HCV; 3.2% among patients with transfusion-associated non-A, non-B, non-C hepatitis; and 2.8% among controls. Patients with transfusion-associated HCV were more likely than controls to develop cirrhosis (odds ratio, 7.8 [95% CI, 4.0 to 15.1]). A history of heavy alcohol abuse was associated with a fourfold increased risk for cirrhosis. Hepatitis C virus infection plus a history of heavy alcohol abuse led to a substantial increase in risk for cirrhosis (odds ratio, 31.1 [CI, 11.4 to 84.5]) compared with controls without such a history. CONCLUSIONS: Heavy alcohol abuse greatly exacerbates the risk for cirrhosis among patients with HCV infection. This finding emphasizes the need to counsel such patients about their drinking habits.

Genomic and molecular evolutionary analysis of a newly identified infectious agent (SEN virus) and its relationship to the TT virus family.

A new group of transmissible single-stranded (ss) DNA viruses (SENV) distantly related to the large TT virus (TTV) family was recently identified. Eight different SENV isolates have been found, some with an association with posttransfusion hepatitis. A phylogenetic analysis of near-complete open-reading frame 1, including conserved motifs and excluding recombinant regions, was performed. The analysis used TTV-like minivirus as an outgroup, to determine a root of the phylogenetic tree, and compared 8 SENV isolates, 6 prototype TTV isolates, and 7 TTV variants (including SANBAN, TUS01, PMV, and YONBAN). Four distinct clusters separated by a bootstrap value of 100% were observed. YONBAN isolates formed a distinct outer group, representing the earliest recognized phylogenetic divergence (group 1). Prototype TTV formed group 2, PMV formed group 3, and SENV, SANBAN, and TUS01 isolates formed group 4, the most recently evolved group. This taxonomic classification suggests that these circular ssDNA viruses probably evolved from a common ancestor virus.

Differential CD4(+) and CD8(+) T-cell responsiveness in hepatitis C virus infection.

This study was performed to compare the vigor and phenotype of virus-specific CD4(+) and CD8(+) T-cell responses in patients with different virologic and clinical outcomes after hepatitis C virus (HCV) infection. The results show that a vigorous and multispecific CD4(+) proliferative T-cell response is maintained indefinitely after recovery from HCV infection whereas it is weak and focused in persistently infected patients. In contrast, the HCV-specific CD8(+) T-cell response was quantitatively low in both groups despite the use of sensitive direct ex vivo intracellular interferon gamma (IFN-gamma) staining. Furthermore, although HCV-specific cytolytic CD8(+) memory T cells were undetectable ex vivo, they were readily expanded from the peripheral blood of chronically HCV-infected patients but not from recovered subjects after in vitro stimulation, suggesting that ongoing viremia is required to maintain the HCV-specific memory CD8(+) T-cell response. HCV-specific CD8(+) T cells displayed a type 1 cytokine profile characterized by production of IFN-gamma despite persistent HCV viremia. The paradoxical observation that HCV-specific CD4(+) T cells survive and CD8(+) T cells are lost after viral clearance while the opposite occurs when HCV persists suggests the existence of differential requirements for the maintenance of CD4(+) and CD8(+) T-cell memory during HCV infection. Furthermore, the relative rarity of circulating CD8(+) effector T cells in chronically infected patients may explain the chronic insidious nature of the liver inflammation and also why they fail to eliminate the virus.