Prevalence of hepatitis C and G virus infection in chronic hemodialysis patients

An RNA virus designated hepatitis G virus (HGV) has been recently identified in patients with acute and chronic liver disease. HGV is transfusion transmissible, it has global distribution, and it is present in the volunteer blood donor population in the United States. One hundred sixty patients undergoing maintenance hemodialysis at the University of Miami-affiliated unit were evaluated. There were 99 men and 61 women ranging in age from 22 to 80 years. Sixty percent had a history of blood transfusion, 6% had a history of drug abuse, and 9% were infected with the human immunodeficiency virus. HGV-RNA was detected by reverse-transcriptase polymerase chain reaction with amplification of two independent regions (5'-nontranslated region and NS5a coding region). Detection of digoxigenin-labeled amplification products with specific capture probes to the coding and noncoding regions was performed with the Enzymun-test DNA on an ES-300 Immunoassay System (Boehringer-Mannheim, Mannheim, Germany). Hepatitis C antibodies were measured with anti-hepatitis C virus enzyme-linked immunosorbent third-generation assays and hepatitis C virus RNA by reverse-transcriptase polymerase chain reaction. There were 32 (20%) patients with detectable HGV RNA with both primer pairs. Because of possible mutations, the HGV virus may be detectable only with one primer pair. We considered the latter as indeterminate: 12 had detectable levels to the NS5a region only, seven to the 5'-nontranslated region, and six had borderline results. Detectable and indeterminate samples were confirmed by repeat measurements in a new blood sample. Seven of 24 (29%) patients with detectable hepatitis C virus RNA had coexisting HGV with one or both HGV primer pairs (four with both and three with one). Five patients were hepatitis B surface antigen positive and HGV negative. We conclude that HGV infection is prevalent in our dialysis patients. The clinical significance of HGV infection remains to be established.

High prevalence of hepatitis G virus infection compared with hepatitis C virus infection in patients undergoing chronic hemodialysis

A recently discovered non-A-E hepatitis virus has been designated as hepatitis G virus (HGV) and identified as a new member of the Flaviviridae family. Infection by this virus is thought to be associated with blood-borne hepatitis and usually in the presence of hepatitis C or hepatitis B virus (HBV) infection. In this study, the presence of HGV-RNA in serum or plasma and the prevalence of antibodies against an HGV envelope protein (E2) were investigated in patients undergoing chronic hemodialysis using a sensitive reverse-transcriptase polymerase chain reaction and an enzyme-linked immunosorbent assay, respectively. HGV-RNA was detected in 19 of 112 patients investigated (17%) and anti-E2 antibodies were detected in 15 of 106 patients studied (14.2%). With the exception of two patients, the appearance of anti-E2 is associated with the clearance of serum HGV-RNA. The total prevalence of current (HGV-RNA positivity) and/or past (anti-E2 positivity) HGV infection in this patient population is thus 28.6% (32 of 112 patients were positive for serum HGV-RNA and/or anti-E2 antibodies). In apparently healthy blood donors, serum HGV-RNA was detected in four of 358 individuals (1.12%) and anti-E2 was not detected in 50 individuals investigated. From the 19 patients with serum HGV-RNA positivity, nine were coinfected with other hepatitis viruses (seven with HBV; one with HBV, hepatitis C virus [HCV], and hepatitis D virus; and one with HBV and cytomegalovirus). Thirteen of 15 patients with anti-E2 positivity (10 were positive for only anti-E2 and three were also positive for anti-HBc) had no detectable HGV-RNA. In two patients, both HGV-RNA and anti-E2 antibodies were concomitantly present (both patients were coinfected with HCV or HBV). Of the HGV-infected patients, only three who were coinfected with HBV showed elevated serum alanine aminotransferase levels. The serum HCV-RNA and/or anti-HCV were detected in five (4.5%) of 112 patients. From these findings, we conclude that there is a high prevalence of HGV infection (28.6%) compared with HCV (4.5%) in patients undergoing hemodialysis in our hospital. However, approximately 50% of patients had spontaneously lost the viremia and developed anti-HGV-E2 antibodies. We confirm that HGV infection alone is not associated with elevated serum transaminases, and the appearance of anti-HGV-E2 is usually accompanied with clearance of serum HGV-RNA. In contrast to the results of our previous study, the majority of patients infected with HGV are not coinfected with HCV, indicating that HGV is capable of independent transmission. It is likely that there is a preferential HGV acquisition in the hemodialysis unit. The clinical significance of long-term infection with HGV remains to be established.

Past and present hepatitis G virus infections in areas where hepatitis C is highly endemic and those where it is not endemic

We reported previously on an area in Japan where over 30% of the inhabitants were positive for hepatitis C virus (HCV) antibody. In the present study, clinical features of hepatitis G virus (HGV) infection in this area of high endemicity were compared to those in an area where HCV is not endemic. A total of 400 individuals were selected randomly from those who were medically screened for liver disease in 1993; 200 were from the high-endemicity area, and the other 200 were from the no-endemicity area. HGV RNA was measured by reverse transcription and PCR with primers in the 5' noncoding region. Antibody to HGV envelope protein E2 was measured by an enzyme-linked immunosorbent assay. Prevalence of any HGV marker in the high-endemicity area (32%) was significantly (P < 0.0001) higher than that in the no-endemicity area (6%); similar differences, 32% versus 3% (P < 0.0001), had been observed for HCV markers (HCV RNA and HCV antibody). In areas of both high and no endemicity, HCV markers were significantly more prevalent in individuals with any HGV marker than in those without HGV markers, and age-specific prevalence of HGV markers was distributed similarly to that of any HCV marker. Among possible routes of HGV transmission that were analyzed, folk medicine was significant in the high-endemicity area, but blood transfusion was the major route in the no-endemicity area. The rate of accompanying viremia in HGV infection (15%) was significantly lower than that in HCV infection (78%) (P < 0.0001). In conclusion, HGV infection was highly prevalent in the area of high HCV endemicity and was closely associated with HCV infection. HGV seemed to be transmitted via the practice of folk medicine as well as blood transfusion. HGV resulted in a chronic carrier state less frequently than did HCV.

Hepatitis G virus does not cause significant liver disease after liver transplantation

The aim of this study was to determine the prevalence of infection with the newly described hepatitis G virus (HGV) in a liver transplant cohort, and to establish the frequency and nature of hepatitis in those with and without HGV infection. A reverse transcriptase-polymerase chain reaction technique was employed to determine viraemia in the patients, and liver biopsies taken at different times after transplantation were assessed histologically. Hepatitis G virus RNA was detected in 47% of the liver transplant recipients investigated. Those positive for HGV had received significantly more blood or blood products than the HGV-negative patients. The frequency of abnormal liver function tests was similar in HGV-positive and HGV-negative recipients. Bile duct epithelial cell damage was more frequently seen in those with HGV viraemia. This study indicates that almost half of the liver transplant recipients in Northern England are positive for HGV, and that infection is associated with exposure to blood and blood products. It appears that, in the immunosuppressed patient, HGV does not cause clinically significant liver disease, at least up to 2 years after transplantation. If HGV infection is associated with hepatitis outside this clinical setting, it is likely that the liver damage is immunopathologically mediated rather than as a result of direct viral cytotoxicity.

Humoral immune response to the E2 protein of hepatitis G virus is associated with long-term recovery from infection and reveals a high frequency of hepatitis G virus exposure among healthy blood donors

The second envelope protein (E2) of the hepatitis G virus (HGV) was expressed in Chinese hamster ovary (CHO) cells and showed a molecular weight of approximately 60 to 70 kd, with 15 to 25 kd of the size contributed by N-linked glycosylation. An enzyme-linked immunosorbent assay (ELISA) using HGV-E2 was developed to test for antibodies to this protein (anti-E2) in human sera. High sensitivity was achieved by developing monoclonal antibodies (mAbs) to HGV-E2, which were used as capture antibodies in the ELISA. Our studies revealed that 16% of healthy Spanish blood donors were exposed to HGV, indicating that additional routes of viral transmission besides parenteral exposure might exist. An even higher prevalence of exposure to HGV (52%-73%) was found in several groups at risk of parenteral exposure to infectious agents, i.e., intravenous drug users, transfusion history, hemophiliacs, and hepatitis C virus (HCV)-positive patients. Most anti-E2-positive patients were HGV-RNA-negative and vice versa, indicating an inverse correlation of these two viral markers. A panel of 16 posttransfusion patients followed for up to 16 years revealed that patients who develop an anti-E2 response become HGV-RNA-negative, while patients who do not develop anti-E2 are persistently infected. Immunity to HGV seems to be long-lasting, because circulating antibody to E2 could still be detected 14 years after seroconversion. Sequence comparisons showed that E2 is highly conserved among isolates collected worldwide, indicating that immune escape variants are not common in HGV infections. This reflects on a molecular level why HGV infections usually are cleared spontaneously by the host. However, possible mechanisms of HGV persistence, as found in some patients, remain to be elucidated.

Thyroid abnormalities in chronic viral hepatitis and their relationship to interferon alfa therapy

The prevalence of antithyroid peroxidase antibodies (ATPO) and/or of thyroid dysfunction was studied in 422 patients with chronic viral hepatitis C, B, and D. Baseline results were compared with those during and 6 months after interferon alfa (IFN-alpha) therapy. The overall prevalence of ATPO among untreated patients was 14.1%, with no significant differences between chronic hepatitis C, B, or D, as well as between males and females. However, high ATPO titers (> or = 18 IU/mL) clustered significantly among females (8.7% vs. 3.4%; P = .022), especially those with chronic hepatitis C (11.2% vs. 3.6%; P = .036). Before treatment, 3.7% of the patients had thyroid dysfunction, mostly hypothyroidism (3.5%), the latter increasing to 14.3% among patients with ATPO titers > or = 18 IU/mL. IFN-alpha treatment significantly increased overall thyroid dysfunction (9.7%; P = .001) and hypothyroidism (7.8%; P = .01), particularly among patients with high baseline ATPO (38.5%; P = .0002). Six months after stopping IFN-alpha treatment, the prevalence of thyroid dysfunction was 8.0%, still significantly higher than at baseline. By multivariate analysis, the only predictor positively associated with pre- or on-treatment hypothyroidism was the baseline titer of the ATPO antibodies (relative risk [RR], 3.0 and 3.8 per each log titer increase, respectively). In conclusion, patients with chronic viral hepatitis on IFN-alpha treatment exhibit an almost threefold increase of baseline thyroid dysfunction, persisting long after the end of therapy. High ATPO titers, clustering among females, particularly those with hepatitis C, represent the only predictor of pre- and on-treatment hypothyroidism by multivariate analysis. Patients with chronic viral hepatitis, especially females, should be tested for ATPO and thyroid function and monitored during and posttreatment for free thyroxin (FT4) and thyroid-stimulating hormone (TSH) levels.

Hepatitis G viral RNA in serum and in peripheral blood mononuclear cells and its relation to HCV-RNA in patients with clotting disorders

The hepatitis G virus (HGV) has recently been identified as a new member of the Flaviviridae family. Infection by this virus is thought to be associated with blood borne hepatitis. In this study, the presence of HCV- and HGV-RNAs in serum or plasma (175 patients) and in peripheral blood mononuclear cells (PBMC) (133 patients) was investigated in patients with clotting disorders using a sensitive reverse transcriptase polymerase chain reaction (RT-PCR). HGV-RNA was detected in serum of 26 patients (14.8%). In apparently healthy blood donors, serum HGV-RNA was detected in 4 of 358 individuals investigated (1.12%). Ninety two percent of the 26 serum HGV-RNA positive patients had coinfection with the hepatitis C virus (HCV), especially with HCV genotype 1b, the most common genotype in Belgium. Of these coinfected patients, 15 (62.5%) showed elevated serum ALT levels. Two patients who were solely infected with HGV had normal serum ALT.HGV-RNA in PBMC was found in 18 patients, of whom 3 were negative for serum HGV-RNA. As in case of HCV, HGV-RNA in PBMC is preferentially sensitive to interferon treatment. Nevertheless, rapid reappearance of HGV-RNA in PBMC was observed after cessation of treatment. In one patient, persistent serum ALT elevation seems to be associated with continued HGV viremia, despite the disappearance of serum HCV-RNA.

Detection of antibodies to a putative hepatitis G virus envelope protein

BACKGROUND

A flavivirus designated hepatitis G virus (HGV) has been isolated from the serum of patients with non-A-E hepatitis. Hitherto, the presence of HGV RNA in serum has been detected with the reverse transcription-polymerase chain reaction (RT-PCR) amplification method. We have now developed an immunoassay for antibodies against an HGV protein.

METHODS

Recombinant HGV envelope protein E2 was used as antigen in an ELISA. 80 blood donors, 99 intravenous-drug users, and 11 patients with acute post-transfusion hepatitis were tested for antibodies to E2. The HGV-RNA status was assessed by RT-PCR.

FINDINGS

Anti-E2 seroprevalence was 9% among the blood donors and 41% among the drug users; HGV-RNA prevalence was 2.5% and 38%, respectively. Whereas anti-E2 prevalence increased with the duration of drug use, HGV-RNA prevalence declined in parallel. In each group, the presence of anti-E2 and HGV RNA was almost mutually exclusive: none of the blood donors and only 4% of the drug users were positive for both markers at the same time. Of the 11 post-transfusion patients--who were all HGV-RNA positive and anti-E2 negative at the onset of disease--four developed antibodies to E2 during the following year, and two of the four subsequently became HGV-RNA negative.

INTERPRETATION

We conclude that a humoral immune response to E2 is associated with loss of detectable HGV viraemia. Thus, E2-specific antibodies might serve as a useful marker for diagnosing recovery from HGV infections. The immunoassay we describe should facilitate investigation of suspected infections and may be helpful in the elucidation of the clinical significance of HGV.

Identification of GBV-C hepatitis G RNA in chronic hepatitis C patients

Sera from patients with chronic hepatitis C were examined for the presence of GBV-C/HGV RNA by RT-PCR. The amplified products, derived from the 5' non-coding, NS3, and NS5a regions, were detected in 19 (19%) of the 100 HCV RNA-positive samples. Analysis of GBV-C/HGV prevalence rates revealed that dual infections are related to shared parenteral risk factors. Intravenous drug abuse and multiple transfusions were the factors clearly associated with a simultaneous HCV and GBV-C/HGV infection. Apart from this, patients with dual infections had a statistically significant lower mean age compared to those patients infected solely by HCV. Determination of HCV genotypes involved in GBV-C/HGV coinfection by RFLP analysis showed no correlation between the presence of GBV-C/HGV and a distinct HCV genotype. The study demonstrates that, based on the assessment of risk criteria, GBV-C/HGV is transmitted efficiently parenterally and is frequently linked to hepatitis C coinfection, regardless of HCV genotype.

Hepatitis G virus infection: clinical characteristics and response to interferon

A new member of the Flaviviridae family has recently been cloned and completely sequenced. The new virus, tentatively named hepatitis G virus (HGV) and known to be closely related to GB virus C (GBV-C), is transmitted by blood and blood products, intravenous drug use and other behaviour associated with a high risk of parenteral exposure to blood. The association of the virus with hepatitis is demonstrated by the presence of raised liver transaminase (alanine aminotransferase, ALT) levels in patients infected with HGV in the absence of other identifiable causes of hepatitis. No patient sera from groups exposed to blood and blood products were found to be positive when tested for the presence of GBV-A or GBV-B sequences, two other recently described flaviviruses. Forty-five per cent of the HGV-infected patients investigated had normal ALT suggesting the existence of a normal carrier state. Persistent infection of up to 13 years duration was observed. Co-infection with hepatitis B or hepatitis C viruses (HBV and HCV) was commonly seen presumably because of shared risk factors. None of five patients with fulminant hepatic failure was positive for HGV infection. The virus is sensitive to interferon-alpha, but sustained responses were not seen with the treatment regimens used for HBV and HCV. Viral titres increased during immunosuppression following liver transplantation and the higher levels of viraemia were in one case accompanied by elavated ALT. Whether HGV (GBV-C) replicates in the liver in some or all cases remains to be established. Preliminary data suggest that it is present within peripheral blood lymphocytes.

Detection of the hepatitis G virus genome among injecting drug users, homosexual and bisexual men, and blood donors

The recently identified hepatitis G virus (HGV) is parenterally transmitted; the impact of sexual transmission is unknown. Moreover, it is unclear what proportion of HGV-infected persons may develop persistent viremia. Sera from injecting drug users (IDUs), non-drug-injecting homosexual and bisexual men with high levels of sexual risk behavior, and blood donors were tested for HGV RNA and hepatitis C virus (HCV) RNA by reverse transcriptase-polymerase chain reaction and for antibodies to human immunodeficiency virus, hepatitis B virus, and HCV. HGV RNA was detected in 33% of IDUs (n = 130), 11% of homosexual and bisexual men (n = 101), and 2% of blood donors (n = 90). HGV RNA seroprevalence significantly decreased with increasing time since first drug injection, whereas the seroprevalences of both HCV RNA and anti-HCV antibody increased. Thus, a high proportion of HGV-infected persons may clear the virus and develop protective antibodies. The relatively high HGV RNA prevalence among non-drug-injecting homosexual and bisexual men indicates that sexual contact may be another important route of HGV transmission.

Hepatitis G virus RNA in the serum of patients with elevated gamma glutamyl transpeptidase and alkaline phosphatase: a specific liver disease? [corrected]

We tested the sera of 67 consecutive patients for hepatitis G virus (HGV) RNA by reverse transcriptase-polymerase chain reaction (RT-PCR). These patients (42 males and 25 females, median age 35 years, range 13-64 years) had liver disease of unknown aetiology and were without markers of hepatitis (A-E) viruses or signs of genetically determined, autoimmune, alcoholic or drug-induced liver disease. The controls in this study were 110 patients (50 females and 60 males, median age 45 years, range 9-65 years) with chronic hepatitis B virus (HBV) infection (19 patients) or hepatitis C virus (HCV) infection (91 patients). Ten of 67 (14.9%) patients with cryptogenic disease were positive for HGV RNA by at least three separate tests; HGV RNA was also detected in one of 19 (5.3%) hepatitis B surface antigen (HBsAg) carriers and in nine of 91 (16.6%) patients with antibody to HCV. These data suggest that HGV occurs as frequently in HCV-infected patients as in those with cryptogenic disease. Elevated serum gamma glutamyl transpeptidase (gamma-GT) (higher than twice the normal value) and alkaline phosphatase levels were found in eight of 10 (80%) HGV RNA positive patients and in six of 57 (10.5%) HGV RNA negative patients (P < 0.0001). Five (50%) HGV RNA positive patients had non-specific inflammatory bile duct lesions. A statistically significant difference was observed between HGV RNA positive and negative patients with chronic HBV or HCV infections (P < 0.029). Therefore, the spectrum of liver disease associated with HGV is wide, but a characteristic lesion of the bile duct leading to elevation of cholestatic enzymes might be specific for this virus.

[Sesamoid bone complex and hallux valgus deformity. A retrospective analysis of 82 Mitchell osteotomies]

The aim of the operative treatment of the hallux valgus deformity is to correct the medial luxation of the first metatarsal head out of the sesamoid complex, the restoration of a congruent joint, the patient after treatment should be painfree. 82 patients were available for an independent clinical and radiological review. The median follow up was 32 months. The evaluation of the results are based on objective and subjective assessment of the patients as well as on radiographic criteria, such as hallux valgus angle, intermetatarsal angle, shortening of the first metatarsal bone, subluxation, lateral positioning of the osteotomized MT I-head and position of the sesamoid complex. Depending on the degree of "lateralisation" of the sesamoid complex seven groups were defined: 0/0, 1/0, 1/1, 2/1, 2/2. 2/3, 3/3 following Appel. Following objective criteria 61% of the patients were evaluated excellent or good, following subjective criteria 77% were evaluated excellent or good. Isolated parallel shifting seems to be sufficient in mild forms of hallux valgus (sesamoid complex group 2/2 or less), while the severe subluxation in the metatarsophalangeal joint (sesamoid complex group 2/3, 3/3) requires an additional lateral wedge osteotomy.

Reverse transcription-PCR detection of hepatitis G virus

Hepatitis G virus (HGV) was recently identified as a new member of the Flaviviridae, but its clinical significance is still unclear. Since no immunoassay for the diagnosis of HGV is available, we developed a sensitive reverse transcription-PCR (RT-PCR) assay to facilitate the detection of the viral genome by mass screening in the clinical laboratory. Sequences within the 5'-noncoding region and within the putative NS5a region are independently amplified in the presence of digoxigenin-11-dUTP and are detected by hybridization with biotinylated capture probes binding to a streptavidin-coated matrix. Semiquantitative Enzymun-Test DNA detection via chemiluminescence can be performed either in a microtiter plate format or on fully automated ES 300 machines. We were able to detect at least 8 x 10(2) genome equivalents per ml of serum using both primer pairs. HGV was shown to be present in 43 of 130 (33%) serum samples from intravenous drug abusers with a high risk of parenteral exposure. However, only two of the patients were positive when the NS5a primers only were used, and only one patient was positive when only the 5'-noncoding region primers were used, demonstrating the increased sensitivity of HGV detection with two sets of primers. Among these patients, there was no obvious correlation with other viral infections like hepatitis B virus, hepatitis C virus, or human immunodeficiency virus. Within a blood donor panel, 3 of 92 (3%) samples were found to be HGV positive, suggesting that donated blood may need to be screened for HGV.

Analysis of the p53 and MDM-2 gene in acute myeloid leukemia

The MDM-2 (murine double minute 2) gene codes for a cellular protein that can bind to the p53 tumor suppressor gene product, thereby functioning as a negative regulator of p53. In order to define the role of the MDM-2 gene in the pathogenesis of human acute myeloid leukemia, the expression and the sequence of the MDM-2 gene were examined in samples of bone marrow and/or peripheral mononuclear cells of 38 patients by using immunostaining, polymerase chain reaction (PCR), single strand conformation polymorphism, and sequencing. Immunohistochemical staining detected a weak accumulation of the MDM-2 protein in AML patients of FAB classification M4 and M5. RT-PCR analysis revealed a heterogeneous expression pattern of MDM-2 mRNA in AML samples of different FAB classification. An increased level of MDM-2 mRNA expression was observed in 17 of 38 AML patients when compared to normal controls. No structural changes in a 488 bp region extending from nucleotide 890 to 1378 of the MDM-2 cDNA were detected using RT-SSCP and sequence analysis. In addition, heterogeneous expression of p53 transcripts was found with the highest p53 mRNA levels in AML M4 and M5. Interestingly, there seems to be a correlation between the relative ratios of p53 and MDM-2 mRNA levels in AML M4 and M5: in 15 of 23 cases high p53 mRNA expression was directly associated with high levels of MDM-2 transcripts. An exclusively intranuclear p53 immunostaining pattern was found in 10 of 16 (58%) AML FAB M4 and M5, whereas the remaining AML samples tested were negative for p53 (0/10). Using RT-SSCP analysis and direct sequencing of the RT-PCR amplification products of p53 exon 5-8, we observed that only 1 of 38 AML patients showed a point mutation in the p53 gene. This missense mutation occurred in the evolutionary highly conserved region of p53 at codon 255 (Ile to Phe). These data indicated that structural alterations of the p53 gene do not play an important role in the initiation and progression of AML. However, abrogation of p53 tumor suppressor function due to MDM-2 overexpression may be an alternative molecular mechanism by which a subset of AMLs may escape from p53-regulated growth control.

Identification of GBV-C hepatitis G RNA in chronic hepatitis C patients

Sera from patients with chronic hepatitis C were examined for the presence of GBV-C/HGV RNA by RT-PCR. The amplified products, derived from the 5' non-coding, NS3, and NS5a regions, were detected in 19 (19%) of the 100 HCV RNA-positive samples. Analysis of GBV-C/HGV prevalence rates revealed that dual infections are related to shared parenteral risk factors. Intravenous drug abuse and multiple transfusions were the factors clearly associated with a simultaneous HCV and GBV-C/HGV infection. Apart from this, patients with dual infections had a statistically significant lower mean age compared to those patients infected solely by HCV. Determination of HCV genotypes involved in GBV-C/HGV coinfection by RFLP analysis showed no correlation between the presence of GBV-C/HGV and a distinct HCV genotype. The study demonstrates that, based on the assessment of risk criteria, GBV-C/HGV is transmitted efficiently parenterally and is frequently linked to hepatitis C coinfection, regardless of HCV genotype.