Prevalence and clinical role of GBV-C infection after cardiac surgery in childhood: a study on 414 patients

OBJECTIVES

GB-virus C (GBV-C) and hepatitis C virus (HCV) share similar modes of transmission. We, therefore, examined the prevalence and clinical role of GBV-C and HCV in patients after cardiac surgery in childhood.

METHODS

We analysed blood samples of 414 patients and compared them to 487 controls. Evidence of liver disease and risk factors for infection was analysed.

RESULTS

Overall prevalence of GBV-C infection was 22.5% in the patients, compared to 6.2% in the controls (HCV infection 11.3 vs. 0.7%). GBV-C RNA was detected in 8.2% of the patients vs. 3.7% in the controls (HCV RNA in 6 and 0%, respectively). Eleven patients had detectable RNA of GBV-C and HCV. 63.4% of patients infected with GBV-C and 46.8% of patients infected with HCV cleared the virus from circulation. GBV-C infection was not associated with hepatitis. Liver disease was not more frequent in patients co-infected with HCV and GBV-C.

CONCLUSIONS

before 1991 have a substantial risk for HCV and GBV-C infection. However, GBV-C infection seems not to be associated with a liver disease. Co-infection with GBV-C and HCV has no influence on long-term clinical outcome or viral clearance of HCV infection.

GB virus C during the natural course of HIV-1 infection: viremia at diagnosis does not predict mortality

OBJECTIVE

To investigate whether GBV-C viremia at diagnosis of HIV-1 infection predicts disease outcome in patients not receiving combination antiretroviral therapy (ART), and whether longitudinal changes in GBV-C viremia are associated with disease progression.

DESIGN

Prospective cohort study.

METHODS

230 patients with a serum sample available for testing obtained within 2 years of HIV-1 diagnosis were followed until either initiation of ART, death, or their last visit to our clinic (median follow-up 4.3 years). Baseline and follow-up serum samples (available from 163 patients) were tested for GBV-C RNA and antibodies against GBV-C envelope E2 protein (anti-E2; signifying resolved GBV-C viremia).

RESULTS

At inclusion, 62 patients (27%) had GBV-C viremia and 69 (30%) had anti-E2. Baseline GBV-C status was not associated with all-cause mortality (P = 0.12), HIV-related mortality (P = 0.18), or development of AIDS (P = 0.84). However, GBV-C RNA was less prevalent in patients with AIDS at inclusion (P = 0.008). Eleven of 44 patients with baseline GBV-C viremia lost GBV-C RNA during follow-up without showing anti-E2 seroconversion. In comparison with anti-E2-negative patients with either persistent absence, persistent presence, or acquisition of GBV-C viremia, these subjects had significantly increased all-cause mortality (P = 0.018), HIV-related mortality (P = 0.007), and AIDS incidence (P < 0.001).

CONCLUSIONS

GBV-C status at diagnosis did not predict disease outcome in this HIV cohort. GBV-C viremia was rare in patients with AIDS, and tended to disappear without occurrence of anti-E2 in patients with progressive disease. This suggests that the GBV-C status of HIV-1-infected patients could be a phenomenon secondary to HIV progression, rather than an independent prognostic factor.

High prevalence of GBV-C/HGV among relatives of GBV-C/HGV-positive blood donors in blood recipients and in patients with aplastic anemia

BACKGROUND

The prevalence of GB virus C (GBV-C)/HGV is high in individuals with parenteral risk factors. The frequency of GBV-C/HGV in blood donors is significantly lower, however it is still far above other parenterally transmitted viruses like HBV and HCV. Therefore, transmission routes apart from parenteral transmission must be considered.

STUDY DESIGN AND METHODS

The purpose of the study was to evaluate the prevalence of GBV-C/HGV in blood donors and relatives of GBV-C/HGV-positive and -negative blood donors. Prevalence was also analyzed in aplastic anemia patients. Samples were tested by RT-PCR and partially by ELISA. Positive isolates were sequenced and phylogenetically analyzed.

RESULTS

A total of 5733 blood donors were PCR tested and 90 were positive (1.6%). Of these, 98 relatives could be tested. Viremia was found in 14.3 percent and anti-E2 in 29.5 percent, whereas only 1.1 percent of the relatives of PCR-negative donors were viremic and 8.5 percent were anti-E2 positive. Probable virus transmission could be shown in two couples and in six mother-child pairs by sequencing of isolates indicating horizontal and vertical virus transmission, respectively. Recipients of GBV-C/HGV RNA-positive blood products were shown to be infected at a rate of 58 percent (18/31). Aplastic anemia patients were positive at a rate of 32 percent (17/53).

CONCLUSION

The high percentage of 14.3 percent of GBV-C/HGV PCR-positive relatives of GBV-C/HGV-positive blood donors suggests intrafamilial transmission. Sequence analyses revealed vertical and horizontal transmission. Although parenteral transmission is highly efficient for GBV-C/HGV (58% of recipients of GBV-C/HGV RNA-positive blood products and 32% of aplastic anemia patients), it appears that sexual and vertical transmission are the most common transmission routes.

[Is GB virus C alias "hepatitis" G virus involved in human pathology?]

GB virus-C alias "hepatitis" virus G was discovered in 1995 as a putative causative virus of non A-E hepatitis. It is a very common virus found in 1 to 5% of eligible blood donors in developed countries. Numerous studies over seven years led to the exclusion of its role as a significant etiological agent of hepatitis. Its in vivo replication site is still unknown. Its direct involvement in the induction of significant hepatic or extra-hepatic diseases could not be demonstrated. However, coinfections with other viruses may contribute to changes in the evolution of both liver disease (negatively) and HIV/AIDS (favourably). Today, no country has decided to screen GBV-C in blood donors. However, more studies are necessary before the absence of influence of GBV-C infection on human health in the context of other viral infections could be confirmed definitely. This article is a review of the literature on a possible involvement of GBV-C in pathologies whether associated or not to other infections.

GB virus C/hepatitis G virus

GB virus C (GBV-C), or hepatitis G virus (HGV), is a recently discovered enveloped RNA virus belonging to the Flaviviridae family. GBV-C/HGV is transmitted by contaminated blood and/or blood products, intravenous drug use, from mother to child, sexually, and possibly through close social contacts. Several reports indicate a high prevalence of GBV-C/HGV viremia (1-4%) within healthy populations in Europe and North America, and an even higher prevalence (10-33%) among residents in South America and Africa. GBV-C/HGV has been suggested to be a causative agent for non-A-non-E hepatitis. However, several contradictory observations suggest that its ability to cause hepatitis is questionable. Taken together most data suggest that GBV-C/HGV is not a major cause of liver disease despite recent data indicating that it may infect and replicate in hepatocytes.

GB virus C/hepatitis G virus infection in patients investigated for chronic liver disease and in the general population in southern Sweden

Serum samples from patients referred for liver biopsy for investigation of suspected chronic liver disease (n = 286) and from healthy middle-aged volunteers (n = 445) were analyzed for markers of exposure to GB virus C/hepatitis G virus (GBV-C/HGV), hepatitis B virus and hepatitis C virus. GBV-C/HGV analyses included GBV-C/HGV PCR for detection of viremia and GBV-C/HGV enzyme-linked immunosorbent assay for anti-GBV-C/HGV E2 antibodies. Liver biopsies were re-evaluated by a hepatopathologist. GBV-C/HGV markers were detected in 97/286 (34%) patients (GBV-C/HGV RNA = 26; anti-GBV-C/HGV E2 antibodies = 74) compared to 86/445 (19%; p < 0.0001) controls (GBV-C/HGV RNA = 7, anti-GBB-C/HGV E2 antibodies = 79). A significantly higher proportion of GBV-C/HGV-exposed subjects in the patient group were viremic compared to controls (27% vs. 8.1%; p = 0.0015). GBV-C/HGV markers were more commonly found in patients with chronic hepatitis B and C. In patients with GBV-C/HGV viremia, a higher occurrence of bile duct degeneration was detected than in non-viremic patients. Markers of GBV-C/HGV infection were over-represented among patients investigated for chronic liver disease, and ongoing GBV-C/HGV viremia was more common in this group than in controls. Apart from a higher prevalence of bile duct degeneration in viremic patients, infection with GBV-C/HGV did not confer any specific histological characteristics.