Persistent hepatitis C virus RNA replication in haemophiliacs: role of co-infection with human immunodeficiency virus

Immunological status does not influence hepatitis c virus or liver fibrosis in HIV-hepatitis C virus-coinfected patients

The possible effects on liver fibrosis and HCV viral load of the immunological status of HIV-HCV-coinfected patients are unclear. A cohort of HIV-HCV-coinfected patients was divided according to the current CD4 counts into poor (≤200/μl, n = 117) or good (≥500/μl, n = 441) immunological status. The groups were compared for diverse HCV- and fibrosis-related parameters. Fibrosis was evaluated by transient elastometry and other noninvasive indexes. Many variables were significantly associated with the immunological status in univariate analyses, including fibrosis parameters. However, in multivariate analyses current immunological status or nadir CD4 were not associated with HCV viral load (p = 0.8 and p = 0.3, respectively), liver fibrosis at the time of evaluation (p = 0.9 for both), or fibrosis progression over time (p = 0.98 and p = 0.8, respectively). The factors independently associated with significant fibrosis, advanced fibrosis, and cirrhosis, as compared with minimal or no fibrosis, were alcohol abuse [OR 3.57 (95% CI 1.43-8.85), p = 0.006; OR 10.10 (3.75-27.03), p < 0.0001; and OR 31.25 (10.6-90.90), p < 0.0001, respectively], HBsAg positivity [OR 9.09 (1.47-55.56), p = 0.02; OR 55.56 (9.80-333.33), p < 0.0001; and OR 43.48 (4.76-476.19), p = 0.0008, respectively], and platelet counts [OR 0.994 (0.989-0.998), p = 0.006; OR 0.990 (0.985-0.995), p = 0.0003; and OR 0.985 (0.979-0.991), p < 0.0001, respectively]. Immunological status did not associate with any fibrosis stage (significant fibrosis, p = 0.7; advanced fibrosis, p = 0.4; and cirrhosis p = 0.9). The current or past immunological status of HIV-HCV-coinfected patients does not seem to have any significant influence on HCV viral load or on the development of liver fibrosis when adjusting for important covariates.

Pitfalls of assessing hepatotoxicity in trials and observational cohorts

The relationship between the use of antiretroviral drugs and the development of hepatic abnormalities has been documented in both randomized controlled trials (RCTs) and observational database studies. Both types of study design are known to have limitations when addressing this issue. Whereas RCTs may enroll a population that is at lower risk for the development of hepatotoxicity, thus underestimating the possible effect of antiretroviral therapy on hepatic abnormalities, observational databases may encompass information from a more heterogeneous group of patients, allowing the drugs to be assessed in a more realistic situation. However, a number of possible biases associated with the use of observational data may limit the conclusions that can be drawn from such studies. I describe some of the benefits and limitations of RCTs and observational data sets when drawing conclusions about the relationship between antiretroviral therapy and the development of hepatic abnormalities.

The association of hepatitis C prevalence, activity, and genotype with HIV infection in a cohort of New York City drug users

Factors associated with serum HCV antibody, HCV RNA level, and HCV genotype were assessed in 557 current and former drug users. Additional assays included HIV antibody, CD4+ lymphocyte counts, HIV viral loads, and hepatitis B markers. Seventy-five percent of subjects were anti-HCV positive, of whom 75% had detectable HCV RNA (median, 5.04 x 10(5) IU/mL; range, 1020-15.7 x 10(6)). On multivariate analysis HCV seropositivity was associated with history of drug injection, HIV seropositivity, and increased age and inversely with drug snorting. Among anti-HCV-positive persons, detectable HCV RNA was independently associated with HIV seropositivity, male gender, and history of injection and inversely associated with hepatitis B surface antigen positivity. Among persons with detectable HCV RNA, higher levels were independently associated with higher HIV viral load, increased age, and genotypes 2a and 2b. These findings demonstrate an association of HCV RNA level with HIV viral load, independent of the level of immunosuppression. However, a substantial degree of the person-to-person variability in the prevalence and level of detectable HCV RNA remains unexplained.

Long-term patterns of hepatitis C virus RNA concentrations in a cohort of HIV seronegative men with bleeding disorders

Little is known about the natural history of hepatitis C virus (HCV) RNA concentrations over the course of infection. The aim of this study was to describe the natural history of HCV RNA concentrations in 85 HIV negative men with bleeding disorders infected with HCV for up to 30 years. HCV RNA concentrations were measured in yearly serum samples using a branched DNA assay. HCV RNA concentrations increased over time in this cohort. Two years after exposure to HCV, 53% of patients had undetectable concentrations and no patients had levels >7 log(10)(genome Eq/ml); by 20 years, these proportions had changed to 23% and 32% respectively. The RNA concentration correlated strongly with alanine aminotransferase (ALT; correlations of 0.41-0.71 depending on stage of infection) and aspartate aminotransferase (AST; 0.20-0.51) levels. Patients with haemophilia A had significantly higher HCV concentrations than those with other disorders. An effect of HCV genotype on HCV RNA concentrations became nonsignificant after excluding patients who were persistently HCV PCR negative and who could not be genotyped. The correlation of HCV RNA concentrations with other markers of liver function, such as ALT, means that studies with clinical outcomes are required to assess whether HCV RNA concentrations provide additional prognostic information to that provided by these other markers.

Comparison of hepatitis C viral loads in patients with or without human immunodeficiency virus

A better understanding of how human immunodeficiency virus (HIV) coinfection affects the course of hepatitis C virus (HCV) infection is required to select patients with HIV who would benefit from current HCV therapy. Between June 1996 and March 2000, HCV RNA levels were quantified for 1,279 patients at the Louisiana State University Health Sciences Center; 28 of these patients were coinfected with HIV. HCV loads were quantified by the Bayer branched-DNA assay with a lower limit of detection of 0.2 Meq/ml. We compared the median HCV RNA levels of for patients coinfected with HIV and HCV and patients infected only with HCV who were in the same age range (23 to 55 years). The median HCV load for the 28 patients coinfected with HCV and HIV (17.8 Meq/ml) was significantly greater (P < 0.05) than that for similarly aged patients infected only with HCV (6.1 Meq/ml). The HCV load did not correlate with age or sex for either group of patients. A significant (R = -0.4; P < 0.05) negative correlation was observed between HCV load and CD4 count in the coinfected group, for whom the CD4 counts at the time of HCV load analysis ranged from 6 to 1,773/mm(3). The increased HCV load in patients coinfected with HCV and HIV compared to that in patients infected only with HCV and the inverse relationship of the HCV load to the CD4 count indicate that immunosuppression results in decreased control of HCV replication. In addition, we report significantly higher HCV loads among coinfected African Americans than Caucasians.

Relation between HIV-1 and hepatitis C viral load in patients with hemophilia

Coinfection with hepatitis C virus (HCV) and HIV-1 is common in patients with hemophilia and in intravenous drug users. Little, however, is known about the relation between HIV-1 and HCV coinfection and the effects on HCV clearance and pathogenesis. We examined data from 207 HIV-1-infected and 126 HIV-1-uninfected patients with hemophilia enrolled in the multicenter Hemophilia Growth and Development Study. Participants were observed during prospective follow-up for approximately 7 years with annual measurements of alanine aminotransferase (ALT), CD4+ cells, and HCV and HIV-1 RNA levels. Clearance of HCV was more likely to occur in those uninfected with HIV-1 (14.3 versus 2.5%; odds ratio [OR] 4.79; 95% confidence interval [CI], 1.63-14.08, p =.005) and was more common with decreasing age (OR, 1.23; 95% CI, 1.04-1.47; p =.017). HCV RNA levels were higher throughout the 7 years of follow-up in those HIV-1-infected (p <.001). In the HIV-1-infected participants, baseline CD4+ cells were inversely related to HCV RNA with every 100-cell increase associated with a 0.19 log10 copy/ml decrease in HCV RNA (p =.002), and HIV-1 and HCV RNA levels were directly related (p =.008). Increasing HCV RNA levels were also associated with significantly higher ALT levels regardless of HIV-1 infection status. These results demonstrate that HIV-1/HCV co-infection is associated with a reduced likelihood of HCV clearance and that higher levels of HCV RNA are associated with increased hepatic inflammation.

Hepatitis B and C virus co-infection and the risk for hepatotoxicity of highly active antiretroviral therapy in HIV-1 infection

OBJECTIVE

To investigate the risk of hepatotoxicity after initiation of protease inhibitor-containing highly active antiretroviral therapy (HAART) for HIV-1 infected patients with chronic hepatitis B virus (HBV) or hepatitis C virus (HCV) co-infection.

DESIGN

Retrospective study with 394 HIV-1-infected patients initiating HAART at a single university clinic.

METHODS

Liver enzyme elevation (LEE) was defined as alanine aminotransferase or aspartate aminotransferase at least five times the upper limit of normal and an absolute increase of > 100 U/l. Relative risks for time to LEE were estimated using Cox proportional hazards models.

RESULTS

Of 394 patients 7% were hepatitis B surface antigen (HBsAg)-positive and 14% were anti-HCV-positive. Patients with chronic hepatitis had a higher risk for LEE compared with patients without co-infection: 37% versus 12% respectively. After adjustment for higher baseline transaminases, the presence of HBsAg or anti-HCV remained associated with an increased risk of LEE - relative risk 2.78 (95% confidence interval, 1.50-5.16) and 2.46 (95% confidence interval, 1.43-4.24) respectively. In patients with LEE, transaminases declined whether HAART was continued or modified. Of patients with chronic HBV infection 38% lost HBeAg or developed anti-HBe after initiation of HAART, and one seroconverted from HBsAg-positive to anti-HBs-positive. However, there was no clear relationship with LEE.

CONCLUSIONS

HIV-1-infected patients co-infected with HBV or HCV were at considerably higher risk of developing LEE when HAART was initiated compared with patients without co-infection, but it is usually not necessary to modify antiretroviral therapy.

Viral Load Monitoring in HIV Infection

Measurement of HIV-1 viral load is now an accepted part of clinical practice for the determination of clinical prognosis and antiretroviral effectiveness in HIV infection. Consensus guidelines have been published on the appropriate use of this testing. Furthermore, recent advances in molecular technology have improved the sensitivity and reproducibility of viral load assays, and these improved assays have provided new insight into the pathogenesis of HIV disease. This article reviews new issues affecting viral load quantification, including viral subtypes, sex, compartmental differences, and other covariables.

Viral infections among patients with hemophilia in the state of Georgia

This analysis evaluated the extent to which infections with selected blood-borne viruses, specifically infection with hepatitis B virus, hepatitis C virus, and/or the human immunodeficiency virus (HIV), continue to contribute to the morbidity of persons with hemophilia. The Georgia Hemophilia Surveillance System collected information on 336 state residents with hemophilia A or B who were followed by a physician in 1994. Data abstracted from medical records included information on demographics, sources of hemophilia care, clinical characteristics, joint range of motion measurements, hospitalization, and results of laboratory testing for hepatitis B, hepatitis C, and the human immunodeficiency virus. Prevalence of infection with one or more of these viruses was determined, and relationships with disease severity, bleeding frequency, and amount of clotting factor prescribed were explored. No child under the age of ten was positive for the human immunodeficiency virus; hepatitis infection was also uncommon in this age group, in contrast to the very high frequency of such infections among older subjects. There was a strong association between HIV positive status and infection with one of the hepatitis viruses. The likelihood of all types of viral infection increased with frequency of bleeding and with amount of clotting factor received. Efforts to prevent transmission of lipid-enveloped viruses via clotting factor have been extremely effective. However, currently infected hemophilia patients will likely experience significant morbidity and mortality due to chronic liver disease and AIDS-related complications.

Progression of HIV in haemophilia

The recent elucidation of the life cycle and dynamics of the human immunodeficiency virus (HIV) and technological advances in development of the HIV RNA PCR assay for sensitive detection of viral load have revolutionized the diagnosis, management, and treatment of HIV infection. Beginning with initial infection, there is unremitting, high-level viral replication that persists throughout the course of HIV infection. The measure of the amount of virus present in plasma, HIV viral load, is the single most important predictor of HIV progression, the best indicator of immune system decline, and the best guide for initiating and monitoring antiviral treatment. Further, HIV viral load has become the new yardstick against which other markers, including CD4 number, age, chemokine receptor mutations, cytotoxic T-cell responses, and neutralizing antibody titers are assessed. For individuals with haemophilia, additional 'markers' may have significant impact on the outcome of HIV disease. Chronic factor concentrate treatment has led to transfusion-associated hepatitis, co-infection with hepatitis C (HCV), and chronic liver disease. The latter may become accelerated with HIV progression and may lead to hepatotoxicity with antiviral drug therapy. Chronic factor concentrate treatment has also been associated with immunosuppression, including both B- and T-cell immune defects. In HIV(+) haemophilic men, this immune deficit has led to lower CD4 counts with HIV progression and poorer CD4 response to antiviral drugs than in gay men. The underlying haemophilic bleeding tendency may result in significant haemorrhage with HIV-associated immune thrombocytopenia and with protease inhibitor antiretroviral therapy. Although AIDS is the leading cause of death in this group, the reduction in the size of the haemophilia population over the next two centuries is estimated to be small, and survival should improve as better antiviral therapeutics are identified.

Therapy for chronic hepatitis B and C infection in haemophilia

Haemophiliacs, until recently, have been at risk of hepatitis B and C infection. Substantial numbers of patients remain persistently infected. Several lines of evidence suggest that these diseases will cause considerable morbidity unless therapy can successfully reduce viraemia and prevent disease progression. Cessation of viral replication may prevent progression to hepatic fibrosis.

Evidence that both HIV and HIV-induced immunodeficiency enhance HCV replication among HCV seroconverters

The objective of this retrospective cohort study is to assess the mechanism by which human immunodeficiency virus type 1 (HIV) influences hepatitis C virus (HCV) replication in injecting drug users. Virological (HCV and HIV RNA levels) and immunological (CD4+, CD8+ cell counts, and anti-CD3 reactivity) parameters were determined in 19 HCV seroconverters in sequential samples over a period of 1 to 9 years. Among these subjects, 10 were HIV-seronegative (HIVneg), 4 were HIV-seropositive (HIVpos), and 5 seroconverted for HIV (HIVsc) during the observation period. HCV RNA levels were higher in HIVpos subjects than in HIVneg subjects. In subjects seroconverting for HIV, HCV, RNA levels increased significantly immediately after HIV seroconversion (P < 0.0001), while they remained stable over time in HIVpos and HIVneg subjects. HCV RNA correlated inversely with CD4+ cell counts in both the HIVpos population (R = -0.22, P < 0.05) and the HIVneg population (R = -0.45, P < 0.0001). In addition, when subjects were stratified according to CD4+ cell counts a significant difference was found in HCV RNA levels between HIVpos and HIVneg subjects with CD4+ cell counts > 500 cells/microliter (P = 0.001), but not in the population with CD4+ cell counts < 500 cells/microliter. In no population was a correlation found between HCV RNA levels and CD8+ cell counts or anti-CD3 reactivity. Both HIV infection and CD4+ cell counts are apparently associated with HCV RNA levels. The direct association, independent of CD4+ cell counts, between HIV infection and HCV replication appears to be stronger than the association between HIV-induced CD4+ cell decline and HCV replication. We conclude that (i) HCV replication is in some way directly influenced by the presence of HIV; (ii) HCV-specific host immunity controls, in part, HCV replication; and (iii) HCV replication increases when the immune system is impaired by HIV.

Does hepatitis C virus co-infection accelerate clinical and immunological evolution of HIV-infected patients?

OBJECTIVE

To study the influence of hepatitis C virus (HCV) co-infection on clinical and immunological evolution of HIV-infected patients.

DESIGN

A longitudinal study of HIV-infected individuals with or without HCV infection, identified at the Infectious Diseases Department of Dijon University Hospital and enrolled in a historical cohort, was performed.

METHODS

One hundred and nineteen HIV-infected people co-infected with HCV and 119 matched individuals infected with HIV alone were included in the cohort (median participation time 3 years; range, 2 months to 11.5 years). Clinical progression was defined as one or more of the following: a 30% decrease in the Karnofsky index; a 20% loss of body weight; an AIDS-defining illness (for non-AIDS patients); death (except by accident, suicide or overdose). Immunological progression was defined as a 50% decrease in the initial CD4 T-cell count (for patients with an initial count > 100 x 10(6) cells/l). Effects of HCV co-infection were evaluated using Kaplan-Meier survival analysis and significance was tested using univariate (log-rank and Peto's tests) and multivariate methods (Cox's model).

RESULTS

In univariate analysis, immunological progression was not statistically different between the HCV-positive group and the HCV-negative group, whereas clinical progression was significantly faster in HCV-positive patients (P < 0.005, log-rank test). In a multivariate Cox model, clinical progression remained significantly associated with infection by HCV [hazard ratio (HR), 1.64; 95% confidence interval (CI), 1.06-2.55; P < 0.05]. Stratified multivariable analysis retained HCV as a significant prognostic factor of clinical progression (HR, 10.9; 95% CI, 1.09-109.3; P < 0.05) and immunological progression (HR, 2.31; 95% CI, 1.16-4.62; P < 0.02) for patients with an initial CD4 count above 600 x 10(6) cells/l.

CONCLUSIONS

Clinical progression is more rapid in HIV-HCV co-infected patients than in HIV-seropositive patients are not infected by HCV. The prognostic value of HCV infection for both clinical and immunological progression is significant at early stages of HIV infection. These findings may argue for active management of hepatitis C infection in co-infected individuals, especially for asymptomatic patients whose CD4 count is above 600 x 10(6) cells/l, to predict and prevent accelerated progression of HCV and HIV diseases.

Tropical aspects of viral hepatitis. Hepatitis C

This paper reviews our current understanding of hepatitis C infection in tropical countries. Since its discovery in 1989, hepatitis C has been recognized as an important disease in many tropical countries. In Egypt the prevalence in some sections of the population may-exceed 20%. In most tropical areas, however, the epidemiology of hepatitis C infection is poorly defined. There are clear variations in the distribution of genotypes in different areas and this may be one of the factors which influence the natural history of infection in different regions of the world. Routes of infection in tropical countries are poorly defined, most carriers having no clear risk factors for infection. There is some speculation that inadequate sterilization of medical equipment may be a route of infection in some areas. A combination of factors may result in an increased risk of hepatocellular carcinoma developing in patients from the tropics infected with hepatitis C and the prognosis may be worse due to co-infection with hepatitis B and human immunodeficiency virus, both of which may lead to accelerated liver disease. Prospects for disease control are poor due to the difficulty of developing a vaccine to the virus.