HIV/HCV co-infection: pathogenesis, clinical complications, treatment, and new therapeutic technologies

Hepatitis C virus testing in adults living with HIV: a need for improved screening efforts

OBJECTIVES

Guidelines recommend hepatitis C virus (HCV) screening for all people living with HIV (PLWH). Understanding HCV testing practices may improve compliance with guidelines and can help identify areas for future intervention.

METHODS

We evaluated HCV screening and unnecessary repeat HCV testing in 8,590 PLWH initiating care at 12 U.S. HIV clinics between 2006 and 2010, with follow-up through 2011. Multivariable logistic regression examined the association between patient factors and the outcomes: HCV screening (≥1 HCV antibody tests during the study period) and unnecessary repeat HCV testing (≥1 HCV antibody tests in patients with a prior positive test result).

RESULTS

Overall, 82% of patients were screened for HCV, 18% of those screened were HCV antibody-positive, and 40% of HCV antibody-positive patients had unnecessary repeat HCV testing. The likelihood of being screened for HCV increased as the number of outpatient visits rose (adjusted odds ratio 1.02, 95% confidence interval 1.01-1.03). Compared to men who have sex with men (MSM), patients with injection drug use (IDU) were less likely to be screened for HCV (0.63, 0.52-0.78); while individuals with Medicaid were more likely to be screened than those with private insurance (1.30, 1.04-1.62). Patients with heterosexual (1.78, 1.20-2.65) and IDU (1.58, 1.06-2.34) risk compared to MSM, and those with higher numbers of outpatient (1.03, 1.01-1.04) and inpatient (1.09, 1.01-1.19) visits were at greatest risk of unnecessary HCV testing.

CONCLUSIONS

Additional efforts to improve compliance with HCV testing guidelines are needed. Leveraging health information technology may increase HCV screening and reduce unnecessary testing.

Human immunodeficiency virus and hepatitis C virus/hepatitis B virus co-infection in Southern Brazil: clinical and epidemiological evaluation

Hepatitis B virus, hepatitis C virus and human immunodeficiency virus share a similar transmission pathway and are often diagnosed in the same patient. These patients tend to have a faster progression of hepatic fibrosis. This cross-sectional study describes the demographic features and clinical profile of human immunodeficiency virus/hepatitis co-infected patients in Paraná, Southern Brazil. A total of 93 human immunodeficiency virus-infected patients attending a tertiary care academic hospital in Southern Brazil were included. Clinical, demographic and epidemiological data were evaluated. Hepatitis B virus and/or hepatitis C virus positive serology was found in 6.6% of patients. The anti-hepatitis C virus serum test was positive in 85% (79/93) of patients, and the infection was confirmed in 72% of the cases. Eighteen patients (19%) were human immunodeficiency virus/hepatitis B virus positive (detectable HBsAg). Among co-infected patients, there was a high frequency of drug use, and investigations for the detection of co-infection were conducted late. A low number of patients were eligible for treatment and, although the response to antiretroviral therapy was good, there was a very poor response to hepatitis therapy. Our preliminary findings indicate the need for protocols aimed at systematic investigation of hepatitis B virus and hepatitis C virus in human immunodeficiency virus-infected patients, thus allowing for early detection and treatment of co-infected patients.

Epidemiological implications of HIV-hepatitis C co-infection in South and Southeast Asia

We sought to profile the epidemiological implication of human immunodeficiency virus (HIV) and hepatitis C virus (HCV) co-infection from South and Southeast Asia by reviewing original studies reporting prevalence of HIV-HCV co-infection and their risk factors. Thirteen papers cited in the PubMed database and published in 2012 and 2013 were reviewed. The overall HCV co-infection prevalence ranged broadly from 1.2 % to 98.5 % among HIV-positive people in South and Southeast Asia. Among HCV seropositive blood donors in Nepal, 5.75 % had HIV co-infection. Injecting drug use (IDU) was one of the key risk factors of co-infection, with HCV infection reaching 89.8 % and 98.5 % among HIV-positive injecting drug users in Vietnam. The most recent data from South and Southeast Asia suggest the urgency of implementation of comprehensive prevention and control strategies of HIV-HCV co-infection.

Disparities and risks of sexually transmissible infections among men who have sex with men in China: a meta-analysis and data synthesis

Background

Sexually transmitted infections (STIs), including Hepatitis B and C virus, are emerging public health risks in China, especially among men who have sex with men (MSM). This study aims to assess the magnitude and risks of STIs among Chinese MSM.

Methods

Chinese and English peer-reviewed articles were searched in five electronic databases from January 2000 to February 2013. Pooled prevalence estimates for each STI infection were calculated using meta-analysis. Infection risks of STIs in MSM, HIV-positive MSM and male sex workers (MSW) were obtained. This review followed the PRISMA guidelines and was registered in PROSPERO.

Results

Eighty-eight articles (11 in English and 77 in Chinese) investigating 35,203 MSM in 28 provinces were included in this review. The prevalence levels of STIs among MSM were 6.3% (95% CI: 3.5–11.0%) for chlamydia, 1.5% (0.7–2.9%) for genital wart, 1.9% (1.3–2.7%) for gonorrhoea, 8.9% (7.8–10.2%) for hepatitis B (HBV), 1.2% (1.0–1.6%) for hepatitis C (HCV), 66.3% (57.4–74.1%) for human papillomavirus (HPV), 10.6% (6.2–17.6%) for herpes simplex virus (HSV-2) and 4.3% (3.2–5.8%) for Ureaplasma urealyticum. HIV-positive MSM have consistently higher odds of all these infections than the broader MSM population. As a subgroup of MSM, MSW were 2.5 (1.4–4.7), 5.7 (2.7–12.3), and 2.2 (1.4–3.7) times more likely to be infected with chlamydia, gonorrhoea and HCV than the broader MSM population, respectively.

Conclusion

Prevalence levels of STIs among MSW were significantly higher than the broader MSM population. Co-infection of HIV and STIs were prevalent among Chinese MSM. Integration of HIV and STIs healthcare and surveillance systems is essential in providing effective HIV/STIs preventive measures and treatments.

Trial Registration

PROSPERO No: CRD42013003721

Hepatitis B and C co-infection among HIV-infected adults while on antiretroviral treatment: long-term survival, CD4 cell count recovery and antiretroviral toxicity in Cambodia

Background

Despite the high burden, there is a dearth of (long-term) outcome data of hepatitis B virus (HBV) and hepatitis C virus (HCV) co-infected patients receiving antiretroviral treatment (ART) in a clinical setting in resource-constrained settings, particularly from Asia.

Methods

We conducted a retrospective cohort study including all adults initiating standard ART (non-tenofovir-based) between 03/2003 and 09/2012. HBV infection was diagnosed by HBV surface antigen detection. HCV diagnosis relied on antibody detection. The independent effect of HBV and HCV on long-term (≥5 years) ART response in terms of mortality (using Cox regression), severe livertoxicity (using logistic regression) and CD4 count increase (using mixed-effects modelling) was determined.

Results

A total of 3089 adults were included (median age: 35 years (interquartile range 30–41); 46% male), of whom 341 (11.0%) were co-infected with HBV and 163 (5.3%) with HCV. Over a median ART follow-up time of 4.3 years, 240 individuals died. Mortality was 1.6 higher for HBV co-infection in adjusted analysis (P = 0.010). After the first year of ART, the independent mortality risk was 3-fold increased in HCV co-infection (P = 0.002). A total of 180 (5.8%) individuals discontinued efavirenz or nevirapine due to severe livertoxicity, with an independently increased risk for HBV (hazard ratio (HR) 2.3; P<0.001) and HCV (HR 2.8; P<0.001). CD4 recovery was lower in both HBV and HCV co-infection but only statistically significant for HBV (P<0.001).

Discussion

HBV and HCV co-infection was associated with worse ART outcomes. The effect of early ART initiation and providing effective treatment for hepatitis co-infection should be explored.

Alcohol misuse and illicit drug use are associated with HCV/HIV co-infection

We studied hepatitis C virus (HCV) prevalence and risk factors for HCV infection in a sample of Brazilian HIV-positive patients. A cross-sectional study was conducted with 580 HIV-positive patients from a specialized HIV/AIDS diagnosis and treatment centre in southern Brazil. All patients were interviewed for socio-demographic and risk factors and tested for HCV antibodies and HCV-RNA detection. A multivariate analysis was performed to identify risk factors for HCV infection. A total of 138 (24%) patients had past or chronic hepatitis C. The following risk factors were associated with HCV infection for each gender: alcohol misuse and injecting drug use in women (P < 0·001) and low educational level, smoking drug use, and injecting drug use in men (P < 0·01). These results suggest that alcohol misuse, low educational level, smoking drug use, and injecting drug use are probable risk factors for HCV infection in HIV-positive patients. This information contributes to an understanding of the epidemiology of HIV/HCV co-infection in Brazil.

A combination microbicide gel protects macaques against vaginal simian human immunodeficiency virus-reverse transcriptase infection, but only partially reduces herpes simplex virus-2 infection after a single high-dose cochallenge

Herpes simplex virus-2 (HSV-2) infection increases HIV susceptibility. We previously established a rhesus macaque model of vaginal HSV-2 preexposure followed by cochallenge with HSV-2 and simian/human immunodeficiency virus-reverse transcriptase (SHIV-RT). Using this model, we showed that a gel containing the nonnucleoside reverse transcriptase inhibitor (NNRTI) MIV-150 in carrageenan (CG) reduced SHIV-RT infection. To evaluate the efficacy of new generation microbicides against both viruses, we first established dual infection after single vaginal cochallenge with SHIV-RT and HSV-2 in HSV-2-naive macaques. All animals (6/6) became HSV-2 infected, with 4/6 coinfected with SHIV-RT. In a control group cochallenged with SHIV-RT and UV-inactivated HSV-2, 2/4 became SHIV-RT infected, and none had detectable HSV-2. Low-level HSV-2-specific antibody and T cell responses were detected in some HSV-2-infected animals. To test a CG gel containing MIV-150 and zinc acetate (MZC), which provided naive animals full protection from SHIV-RT for at least 8 h, MZC (vs. CG) was applied daily for 14 days followed by cochallenge 8 h later. MZC prevented SHIV-RT infection (0/9 infected, p=0.04 vs. 3/6 in CG controls), but only reduced HSV-2 infection by 20% (6/9 infected vs. 5/6 in CG, p=0.6). In HSV-2-infected animals, none of the gel-treated animals seroconverted, and only the CG controls had measurable HSV-2-specific T cell responses. This study shows the promise of MZC to prevent immunodeficiency virus infection (even in the presence of HSV-2) and reduce HSV-2 infection after exposure to a high-dose inoculum. Additionally, it demonstrates the potential of a macaque coinfection model to evaluate broad-spectrum microbicides.

CD4/CD8 ratio is a promising candidate for non-invasive measurement of liver fibrosis in chronic HCV-monoinfected patients

The extent of liver fibrosis is an important factor in prognosis and clinical decision-making in chronic hepatitis C virus (HCV) infection. We investigated CD4/CD8 ratio in HCV-monoinfected and HIV/HCV-coinfected patients, in order to reveal its relation with liver fibrosis. CD4/CD8 ratio in the peripheral blood was assessed by flow cytometry in a cohort of 19 HCV-monoinfected, 14 HIV/HCV-coinfected, ten HIV-monoinfected patients and 15 healthy controls. Liver fibrosis was assessed by transient elastography (n = 25) or by liver biopsy (n = 8). Coinfection with HIV was associated with decreased CD4/CD8 ratios in chronic HCV-infected patients, despite adequate antiretroviral treatment. Furthermore, HCV-monoinfected patients with F3-F4 liver fibrosis demonstrated much lower CD4/CD8 ratios than patients with F0-F2 fibrosis (1.4 versus 2.5, p = 0.023). Similarly, we observed a strong negative correlation between the CD4/CD8 ratio and liver stiffness measured by transient elastography (R = -0.78, p = 0.0006). ROC analysis revealed that CD4/CD8 ratio as a non-invasive marker for fibrosis is very promising (area under the curve 0.8). Although our study was performed with a relatively small number of patients, our findings suggest that the CD4/CD8 ratio is a promising candidate for non-invasive evaluation of liver fibrosis in HCV-monoinfected patients.

Regression of liver fibrosis is progressive after sustained virological response to HCV therapy in patients with hepatitis C and HIV coinfection

There are few data about the long-term histological outcome of HIV-/HCV-coinfected patients after therapy with interferon and ribavirin. We performed an observational study of 216 patients who received therapy against HCV and who had at least three successive transient elastographies (TE) during the follow-up. The primary endpoint was confirmed fibrosis regression, defined as a reduction of at least 1 point in Metavir fibrosis score, confirmed and without worsening in successive TE. At baseline, 23% had fibrosis stage 4 or cirrhosis. Overall, 82 (38%) achieved sustained virological response (SVR), without differences in baseline fibrosis or time of follow-up. Confirmed fibrosis regression was observed in 55% of patients, higher for SVR (71% vs 44%; P < 0.01), and the likelihood of achieving fibrosis regression at 3, 5 and 7 years was 0.17, 0.51 and 0.67, respectively, for SVR patients, in comparison with 0.02, 0.23 and 0.41 for no SVR patients (P < 0.01, log-rank test at any time point). Progressive regression, defined as continuous improvement in successive TE, was observed in 62% of patients with advanced liver fibrosis or cirrhosis who achieved SVR. In a Cox regression model, only SVR (HR, 4.01; 95% CI, 2.33-7.57; P < 0.01) and a younger age (HR, 1.14; 95% CI, 1.05-1.25; P < 0.01; per year) were associated with fibrosis regression. This study confirms that the rate of liver fibrosis regression increases during the follow-up after SVR to interferon therapy in HIV-/HCV-coinfected patients.

Applications and limitations of inflammatory biomarkers for studies on neurocognitive impairment in HIV infection

Despite reduced prevalence of severe forms of HIV-associated neurocognitive disorders (HAND) on current antiretroviral therapy (ART) regimens, milder forms of neurocognitive impairment (NCI) remain prevalent in HIV-infected populations. These mild forms of HAND consist of subtypes, probably reflecting distinct, though possibly overlapping, pathophysiological mechanisms. Factors associated with HAND in HIV patients with prolonged viral suppression on ART include older age, low nadir CD4, active HCV co-infection, and cardiovascular risk factors, but underlying mechanisms and their relationship to innate immune activation, chronic inflammation, and other features of systemic disease are poorly understood. In this article, we discuss applications and limitations of plasma inflammatory biomarkers for studies on HAND in HIV patients on ART and describe an analysis pipeline to reduce common sources of noise and increase likelihood of identifying relevant inflammatory biomarkers. Clinical covariates and comorbidities that influence inflammatory biomarkers, such as aging, obesity, metabolic abnormalities, HCV co-infection, and substance abuse, are also reviewed. As an example for using this analytic pipeline, we present an exploratory study of 22 plasma inflammatory biomarkers (IFN-α 2b and -γ, 16 cytokines/chemokines, sIL-2R, sCD14, HA, and YKL-40) in a cohort of HIV-infected individuals with advanced disease, frequent HCV co-infection, and viral suppression on ART. The identification of inflammatory biomarkers associated with HAND in HIV+ patients on ART may be useful to distinguish between HAND subtypes with distinct pathophysiology, and is important for achieving a systems-level understanding of the biology of these disorders, developing effective therapies, and evaluating therapeutic outcomes.

Hepatitis C virus/HIV coinfection and responses to initial antiretroviral treatment

OBJECTIVE

To explore the relationship between hepatitis C virus (HCV)/HIV coinfection and responses to initial antiretroviral treatment (ART).

METHODS

Four AIDS Clinical Trials Group HIV treatment studies' data were combined to compare initial ART responses between HCV/HIV-coinfected and HIV-monoinfected patients as evaluated by virologic failure, CD4 cell measures, occurrence of AIDS/death and grade 3/4 safety events, using Kaplan-Meier estimates and proportional hazard, regression and mixed effects models, adjusting for baseline covariates.

RESULTS

Of the 3041 included participants, 81% were men, 19% had prior history of AIDS, the median (25th, 75th percentile) baseline HIV RNA was 4.72 (4.38-5.18) log10 copies/ml, and the median (25th, 75th percentile) baseline CD4 cell count was 216.0 (76.5-327.0) cells/μl. The 279 HCV/HIV-coinfected individuals were older (44 vs. 37 years), more likely to be black non-Hispanic (47 vs. 36%), and previous/current intravenous drug user (52 vs. 5%) than the 2762 HIV-monoinfected patients (all P values <0.001). HCV/HIV coinfection was associated with earlier virologic failure, hazard ratio (95% confidence interval): 1.43 (1.07-1.91); smaller mean CD4 cell increase and CD4% increase [-33.8 (-52.2 to -15.4) cells/μl and -1.16% (-1.43 to -0.89%), respectively] over a median of 132 weeks of follow-up; earlier occurrence of grade 3/4 safety event, hazard ratio 1.51 (1.26-1.81); and increased AIDS/mortality, hazard ratio 2.10 (1.31-3.37). Treatment effects comparing antiretroviral regimens were not significantly different by HCV/HIV coinfection status.

CONCLUSION

HCV/HIV coinfection is associated with attenuated response to ART. Results support earlier initiation of HIV therapy and increased monitoring of those initiating ART with HCV/HIV coinfection.

Modeling the impact of hepatitis C viral clearance on end-stage liver disease in an HIV co-infected cohort with targeted maximum likelihood estimation

Despite modern effective HIV treatment, hepatitis C virus (HCV) co-infection is associated with a high risk of progression to end-stage liver disease (ESLD) which has emerged as the primary cause of death in this population. Clinical interest lies in determining the impact of clearance of HCV on risk for ESLD. In this case study, we examine whether HCV clearance affects risk of ESLD using data from the multicenter Canadian Co-infection Cohort Study. Complications in this survival analysis arise from the time-dependent nature of the data, the presence of baseline confounders, loss to follow-up, and confounders that change over time, all of which can obscure the causal effect of interest. Additional challenges included non-censoring variable missingness and event sparsity. In order to efficiently estimate the ESLD-free survival probabilities under a specific history of HCV clearance, we demonstrate the double-robust and semiparametric efficient method of Targeted Maximum Likelihood Estimation (TMLE). Marginal structural models (MSM) can be used to model the effect of viral clearance (expressed as a hazard ratio) on ESLD-free survival and we demonstrate a way to estimate the parameters of a logistic model for the hazard function with TMLE. We show the theoretical derivation of the efficient influence curves for the parameters of two different MSMs and how they can be used to produce variance approximations for parameter estimates. Finally, the data analysis evaluating the impact of HCV on ESLD was undertaken using multiple imputations to account for the non-monotone missing data.

Effect of hepatitis C virus on immunological and virological responses in HIV-infected patients initiating highly active antiretroviral therapy: a meta-analysis

Co-infection of human immunodeficiency virus (HIV) with hepatitis C virus (HCV) is rather common. In the era of highly active antiretroviral therapy (HAART), viral hepatitis could result in adverse outcomes in HIV+ patients. The current meta-analysis aims to evaluate the impact of HCV on immunological and virological responses after HAART initiation in HIV/HCV co-infected individuals by synthesizing the existing scientific evidence. A comprehensive search of electronic databases was performed. Eligible studies were analysed using univariate and multivariate meta-analytic methods. Totally, 21 studies involving 22533 individuals were eligible. The estimated summary difference in CD4 cell counts increase between HIV and HIV/HCV co-infected subjects after 3-12 months on HAART was 34.86 cells/mm(3) [95% confidence interval (CI): 16.82-52.89]. The difference was more prominent in patients with baseline CD4 counts below 350 cells/mm(3) (38.97, 95% CI: 20.00-57.93) and attenuated 2 years later (13.43, 95% CI: 0.83-26.04). The analysis of ratio measures yielded similar findings. The virological control remained unaffected by the presence of HCV (adjusted Hazard Ratio for co-infected patients vs those with HIV alone: 0.99, 95% CI: 0.91-1.07). The bivariate meta-analytic method confirmed the results of the univariate approaches. This meta-analysis supports the adverse effect of HCV on immune recovery of HIV+ patients initiating HAART, especially of those with initially impaired immunologic status. Although this effect diminishes over time, early administration of HAART in the setting of co-infection seems to be justified.

Coinfection with Hepatitis C Virus among HIV-Positive People in the Kathmandu Valley, Nepal

Background:

Previous research has studied the rate of hepatitis C virus (HCV) coinfection among HIV-positive people regardless of their antiretroviral therapy (ART) status. Our objectives were to measure the seroprevalence of HCV both in HIV-positive people receiving ART and in those not receiving ART and to describe the characteristics of coinfected people in the Kathmandu Valley, Nepal.

Methods:

We conducted a cross-sectional survey of 319 HIV-positive people residing in the Kathmandu Valley, Nepal. We screened the participants’ serum samples for HCV antibodies using the Latex Photometric Immunoassay based on third-generation assay.

Results:

A total of 138 (43.3%) participants were HCV positive. The prevalence of HCV coinfection was 96.2% (125 of 130) among participants with lifetime injection drug use (IDU). Among participants not receiving ART, the coinfection rate was 58.1% (50 of 86) compared with 37.8% (88 of 233) among those receiving ART. In multivariable analysis, participants who reported lifetime IDU and were current smokers were more likely to have HCV coinfection. The adjusted odds ratio (AOR) of HCV coinfection for ART was decreased, although it was not statistically significant (AOR = 0.45; 95% confidence interval = 0.13-1.48).

Conclusion:

The high prevalence of HCV coinfection among both individuals receiving ART and those not receiving ART suggests that screening for HCV among HIV-positive people would be useful, in particular, for those with lifetime IDU and soon after their HIV diagnosis.

Variation in both IL28B and KIR2DS3 genes influence pegylated interferon and ribavirin hepatitis C treatment outcome in HIV-1 co-infection

Pegylated-IFN and ribavirin remains the current treatment for chronic HCV infection in patients co-infected with HIV-1, but this regimen has low efficacy rates, particularly for HCV genotype 1/4 infection, has severe side effects and is extremely costly. Therefore, accurate prediction of treatment response is urgently required. We have recently shown that the NK cell gene, KIR2DS3 and a SNP associated with the IL28B gene synergise to increase the risk of chronic infection in primary HCV mono-infected patients. Identification of SNPs associated with the IL28B gene has also proven very powerful for predicting patient response to treatment. Patients co-infected with HIV-1 are of particular concern given they respond less well to HCV treatment, have more side effects and suffer a more rapid liver disease progression. In this study, we examined both IL28B and KIR2DS3 for their ability to predict treatment response in a cohort of HIV-1/HCV co-infected patients attending two treatment centres in Europe. We found that variation in both host genetic risk factors, IL28B and KIR2DS3, was strongly associated with sustained virological response (SVR) to treatment in our co-infected cohort (n = 149). The majority of patients who achieved a rapid virological response (RVR) achieved a SVR. However, it is currently impossible to predict treatment outcome in patients who fail to achieve an RVR. In our cohort, the presence of host genetic risk factors, IL28B-T and KIR2DS3 alleles, resulted in increased odds of treatment failure in these RVR negative patients (n = 88). Our data suggests that testing for host genetic factors will improve predicting treatment responsiveness in the clinical management of co-infected patients, and provides further evidence of the importance of the innate immune system in the immune response to HCV.

Determinants of immunological and virological responses to antiretroviral therapy amongst HIV-infected adults in central Argentina: negative influence of hepatitis C infection

BACKGROUND

The purpose of this study was to update the epidemiological data on the prevalence of coinfection with hepatitis C virus (HCV) and HIV, and to identify whether specific clinical and epidemiological factors influenced the response of HIV-positive adults to highly active antiretroviral therapy (HAART).

METHODS

This retrospective observational cohort study of 238 HIV-infected patients evaluated the effect of different epidemiological and clinical parameters (including HCV coinfection) on therapy response among HIV-infected adults initiating HAART. Multiple logistic regression models were used to identify factors associated with therapy response and estimated risk coefficients.

RESULTS

Seroprevalence of HCV infection in this population was 26% (62/238). We did not observe a significant association between immunological or virological response relating to patient gender or HAART regimen. However, this analysis showed that HCV serological status, age at HIV diagnosis, duration of treatment and WHO clinical stage of AIDS (<200 CD4 cells/ml independently of viral load either < or > to 100,000 copies/ml), were significantly associated with immunological and virological responses to HAART.

CONCLUSIONS

These results show further evidence that hepatitis C serostatus is associated with a reduced response to HAART.

Hepatitis C Virus and HIV Type 1 Co-Infection

Around 33 million people worldwide are living with Human Immunodeficiency Virus (HIV) infection, and approximately 20-30% of HIV-infected individuals are also infected with Hepatitis C virus (HCV). The main form of HCV transmission is via the blood borne route; high rates of co-infection are found in intravenous drug users with HCV prevalence rates as high as 90%. Introduction of effective antiretroviral therapy (ART) has led to a significant decline in HIV-related morbidity, but at the same time the incidence of HCV related liver disease is increasing in the co-infected population. Meta analysis has revealed that individuals who are co-infected with HIV/HCV harbor three times greater risk of progression to liver disease than those infected with HCV alone. Increased risk of progression to Acquired Immunodeficiency Syndrome (AIDS) and AIDS-related deaths is shown among the co-infected patients by some studies, suggesting that HCV infection may accelerate the clinical course of HIV infection. HCV may also affect the incidence of liver toxicity associated with ART, affecting the management of HIV infection. There is a lack of optimal therapeutic approaches to treat HCV infection in HIV co-infected patients. This review discusses recent literature pertaining HIV/HCV co-infection, in addition to providing a snapshot of impact of co-infection on human genome at the level of gene expression and its regulation by microRNAs (miRNAs).

A case of HIV-1 slow seroconversion: diagnostic implications

We report the case of a 30-year-old woman who failed to achieve diagnostic Western blot criteria for HIV-1 infection until 21 months after her initial presentation. This case highlights the importance of suspecting delayed HIV seroconversion in cases with persistently indeterminant Western blots.

HCV clearance from saliva of HIV-HCV-coinfected patients on treatment with interferon plus ribavirin

OBJECTIVE

To determine hepatitis C virus (HCV) RNA clearance from blood and saliva of HIV-HCV-coinfected patients undergoing combined therapy with pegylated interferon plus ribavirin (PEG-IFN-RIB).

SUBJECTS AND METHODS

Study group was formed of 60 HIV-infected patients with chronic hepatitis C who were starting treatment with PEG-IFN-RIB. Blood and saliva samples were taken at baseline, at the end of treatment and 24 and 48 weeks later. A nested RT-PCR technique was used to detect HCV-RNA in saliva.

RESULTS

HCV-RNA was detected in saliva at baseline in 64.7% of patients. Thirty-four patients completed follow-up. The response rate (undetectable HCV-RNA) in blood was 79.4% at the end of treatment; 55.8% at 24 weeks after the end of treatment and 50% at 48 weeks. HCV was detected in saliva of 13 (38.2%) patients at the end of treatment and in 18 (52.9%) patients at 24 and 48 weeks later. Concordance of HCV clearance from blood and saliva reached its maximum value at 48 weeks after the end of treatment (odds ratio, 112.51).

CONCLUSION

In HIV-HCV-coinfected patients responders to PEG-IFN-RIB, the salivary glands do not appear to be a sanctuary site for HCV, although viral clearance from saliva may be slower than from blood.

Effect of HCV infection on cause-specific mortality after HIV seroconversion, before and after 1997

BACKGROUND & AIMS

Individuals with human immunodeficiency virus (HIV) infection frequently also are infected with hepatitis C virus (HCV) (co-infection), but little is known about its effects on the progression of HIV-associated disease. We aimed to determine the effects of co-infection on mortality from HIV and/or acquired immune deficiency syndrome (AIDS), and hepatitis or liver disease, adjusting for the duration of HIV infection.

METHODS

We analyzed data from the 16 cohorts of the Concerted Action on Seroconversion to AIDS and Death in Europe (CASCADE) collaboration, which included information on HCV infection and cause of death. A competing-risks proportional subdistribution hazards model was used to evaluate the effect of HCV infection on the following causes of death: HIV- and/or AIDS-related, hepatitis- or liver-related, natural, and non-natural.

RESULTS

Of 9164 individuals with HIV infection and a known date of seroconversion, 2015 (22.0%) also were infected with HCV. Of 718 deaths, 395 (55.0%) were caused by HIV infection and/or AIDS, and 39 (5.4%) were caused by hepatitis or liver-related disease. Among individuals infected with only HIV or with co-infection, the mortality from HIV infection and/or AIDS-related causes and hepatitis or liver disease decreased significantly after 1997, when combination antiretroviral therapy became widely available. However, after 1997, HIV and/or AIDS-related mortality was higher among co-infected individuals than those with only HIV infection in each risk group: injection drug use (adjusted hazard ratio [aHR], 2.43; 95% confidence interval [CI], 1.14-5.20), sex between men and women or hemophilia (aHR, 3.43; 95% CI, 1.70-6.93), and sex between men (aHR, 3.11; 95% CI, 1.49-6.48). Compared with individuals infected with only HIV, co-infected individuals had a higher risk of death from hepatitis or liver disease.

CONCLUSIONS

Based on analysis of data from the CASCADE collaboration, since 1997, when combination antiretroviral therapy became widely available, individuals co-infected with HIV and HCV have had a higher risk of death from HIV and/or AIDS, and from hepatitis or liver disease, than patients infected with only HIV. It is necessary to evaluate the effects of HCV therapy on HIV progression.

Predictors of Chronic Hepatitis C Evolution in HIV Co-Infected Patients From Romania

BACKGROUND

Due to a recent alarming increase in the number of HIV-HCV co-infected patients in Romania.

OBJECTIVES

A cross sectional study was conducted to assess the baseline predictors of liver disease evolution.

PATIENTS AND METHODS

83 HIV-HCV co-infected patients, untreated for HCV infection, were evaluated for viral replication, liver fibrosis (estimated by a noninvasive marker - FIB4), and plasma levels of IP-10 (interferon-gamma inducible protein 10) - a cytokine associated with an unfavorable outcome of HCV infection.

RESULTS

The median value for HCV viral load was high (6.3 log10 IU/mL), 98.8% of the patients were infected with HCV genotype 1. Although 53% of the patients received antiretroviral therapy (cART), only 31.8% of these achieved undetectable HIV levels. HCV viral load was significantly higher in patients with AIDS (6.4 vs. 6.1 log10IU/mL; P = 0.04), and in those naïve for cART (6.5 vs. 5.9 log10 IU/mL; P = 0.04). Severe fibrosis was directly correlated with immunosupression (56% vs. 17.4%, P = 0.03), HCV replication (6.1 vs. 4.9 log10IU/mL P = 0.008), and IP-10 median values (312 vs. 139 pg/ml, P=0.008). A serum IP-10 level higher than 400 pg/mL was significantly associated with FIB-4 median values (4.09 vs. 1.7, P = 0.004), HCV viral load (6.4 vs. 6.1 log10 IU/mL, P = 0.02) and ALT level (206.8 vs. 112.4 IU/L, P = 0.05).

CONCLUSIONS

An important part of the HIV-HCV co-infected patients had negative baseline predictors for the evolution of HCV infection; their therapeutical management must be conducted with special attention towards adherence and potential overlapping drug toxicities. High concentrations of plasma IP-10 are reliable markers for the severity of liver disease.

Pharmacokinetic interaction between boceprevir and etravirine in HIV/HCV seronegative volunteers

OBJECTIVE

The primary aim of this study was to determine the bioequivalence of boceprevir, an HCV protease inhibitor and etravirine, an HIV non-nucleoside reverse transcriptase inhibitor; area under the concentration time curve (AUC(0,τ)); maximum concentration (C(max)); and trough concentration (C(8) or C(min)) when administered in combination versus alone.

DESIGN

Open-label crossover study in healthy volunteers.

METHODS

Boceprevir, etravirine, and the combination were administered for 11-14 days with intensive sampling between days 11 and 14 of each sequence. Boceprevir and etravirine were quantified using validated liquid chromatography coupled with tandem mass spectrometry and high-performance liquid chromatography/ultraviolet assays, respectively and pharmacokinetics determined using noncompartmental methods. Geometric mean ratios (GMRs) and 90% confidence interval (CI) for the combination versus each drug alone were evaluated using 2 one-sided t tests. The hypothesis of equivalence was rejected if 90% GMR CI was not contained in the interval (0.8-1.25).

RESULTS

Twenty subjects completed study. GMRs (90% CI) for etravirine AUC(o,τ), C(max), and C(min) were 0.77 (0.66 to 0.91), 0.76 (0.68 to 0.85), and 0.71 (0.54 to 0.95), respectively, in combination versus alone. Boceprevir GMRs (90% CI) for AUC(o,τ), C(max), and C(8) were 1.10 (0.94 to 1.28), 1.10 (0.94 to 1.29), and 0.88 (0.66 to 1.17), respectively, in combination versus alone. All adverse events (n = 112) were mild or moderate. Six subjects discontinued: 4 due to rash, 1 due to central nervous system effects, and 1 for a presumed viral illness.

CONCLUSIONS

Etravirine AUC(o,τ), C(max), and C(min)decreased 23%, 24%, and 29%, respectively, with boceprevir. Boceprevir AUC(0,τ) and C(max) increased 10% and C(8) decreased 12% by etravirine. Additional research is needed to elucidate the mechanism(s) and therapeutic implications of the observed interaction.

Monocyte activation in HIV/HCV coinfection correlates with cognitive impairment

Coinfection with human immunodeficiency virus (HIV) and hepatitis C virus (HCV) challenges the immune system with two viruses that elicit distinct immune responses. Chronic immune activation is a hallmark of HIV infection and an accurate indicator of disease progression. Suppressing HIV viremia by antiretroviral therapy (ART) effectively prolongs life and significantly improves immune function. HIV/HCV coinfected individuals have peripheral immune activation despite effective ART control of HIV viral load. Here we examined freshly isolated CD14 monocytes for gene expression using high-density cDNA microarrays and analyzed T cell subsets, CD4 and CD8, by flow cytometry to characterize immune activation in monoinfected HCV and HIV, and HIV-suppressed coinfected subjects. To determine the impact of coinfection on cognition, subjects were evaluated in 7 domains for neuropsychological performance, which were summarized as a global deficit score (GDS). Monocyte gene expression analysis in HIV-suppressed coinfected subjects identified 43 genes that were elevated greater than 2.5 fold. Correlative analysis of subjects' GDS and gene expression found eight genes with significance after adjusting for multiple comparisons. Correlative expression of six genes was confirmed by qPCR, five of which were categorized as type 1 IFN response genes. Global deficit scores were not related to plasma lipopolysaccharide levels. In the T cell compartment, coinfection significantly increased expression of activation markers CD38 and HLADR on both CD4 and CD8 T cells but did not correlate with GDS. These findings indicate that coinfection is associated with a type 1 IFN monocyte activation profile which was further found to correlate with cognitive impairment, even in subjects with controlled HIV infection. HIV-suppressed coinfected subjects with controlled HIV viral load experiencing immune activation could benefit significantly from successful anti-HCV therapy and may be considered as preferential candidates.

Cause-specific life expectancies after 35 years of age for human immunodeficiency syndrome-infected and human immunodeficiency syndrome-negative individuals followed simultaneously in long-term cohort studies, 1984-2008

Parametric and semiparametric competing risks methods were used to estimate proportions, timing, and predictors of acquired immune deficiency syndrome (AIDS)-related and non-AIDS-related mortality among individuals both positive and negative for the human immunodeficiency syndrome (HIV) in the Multicenter AIDS Cohort Study (MACS) and Women's Interagency HIV Study (WIHS) from 1984 to 2008 and 1996 to 2008, respectively. Among HIV-positive MACS participants, the proportion of deaths unrelated to AIDS increased from 6% before the introduction of highly active antiretroviral therapy (HAART) (before 1996) to 53% in the HAART era (P < 0.01); the median age of persons who died from non-AIDS-related causes after age 35 years increased from 49.0 to 66.0 years (P < 0.01). In both cohorts during the HAART era, median ages at time of non-AIDS-related death were younger for HIV-positive individuals than for comparable HIV-negative individuals (8.7 years younger in MACS (P < 0.01) and 7.6 years younger in WIHS (P < 0.01)). In a multivariate proportional cause-specific hazards model, unemployment (for non-AIDS death, hazard ratio (HR) = 1.8; for AIDS death, HR = 2.3), depression (for non-AIDS death, HR = 1.4; for AIDS death, HR = 1.4), and hepatitis B or C infection (for non-AIDS death, HR = 1.8, for AIDS death; HR = 1.4) were significantly (P < 0.05) associated with higher hazards of both non-AIDS and AIDS mortality among HIV-positive individuals in the HAART era, independent of study cohort. The results illuminate the changing face of mortality among the growing population infected with HIV.

When to start, what to start and other treatment controversies in pediatric HIV infection

Over the last decade there have been dramatic changes in the management of pediatric HIV infection. Whilst observational studies and several randomized control trials (RCTs) have addressed some questions about when to start antiretroviral therapy (ART) in children and what antiretrovirals to start, many others remain unanswered. In infants, early initiation of ART greatly reduces mortality and disease progression. Treatment guidelines now recommend ART in all infants younger than 1 or 2 years of age depending on geographical setting. In children >1 year of age, US, European (Paediatric European Network for Treatment of AIDS; PENTA) and WHO guidelines differ and debate is ongoing. Recent data from an RCT in Thailand in children with moderate immune suppression indicate that it is safe to monitor asymptomatic children closely without initiating ART, although earlier treatment was associated with improved growth. Untreated HIV progression in children aged over 5 years is similar to that in adults, and traditionally adult treatment thresholds are applied. Recent adult observational and modeling studies showed a survival advantage and reduction of age-associated complications with early treatment. The current US guidelines have lowered CD4+ cell count thresholds for ART initiation for children aged >5 years to 500 cells/mm3. Co-infections influence the choice of drugs and the timing of starting ART. Drug interactions, overlapping toxicities and adherence problems secondary to increased pill burden are important issues. Rapid changes in the pharmacokinetics of antiretrovirals in the first years of life, limited pharmacokinetic data in children and genetic variation in metabolism of many antiretrovirals make correct dosing difficult. Adherence should always be addressed prior to starting ART or switching regimens. The initial ART regimen depends on previous exposure, including perinatal administration for prevention of mother to child transmission (PMTCT), adherence, co-infections, drug availability and licensing. A European cohort study in infants indicated that treatment with four drugs produced superior virologic suppression and immune recovery. Protease inhibitor (PI)-based ART has the advantage of a high barrier to viral resistance. A recent RCT conducted in several African countries showed PI-based ART to be advantageous in children aged <3 years compared with nevirapine-based ART irrespective of previous nevirapine exposure. Another trial in older children from resource rich settings showed both regimens were equally effective. Treatment interruption remains a controversial issue in children, but one study in Europe demonstrated no short-term detrimental effects. ART in children is a rapidly evolving area with many new antiretrovirals being developed and undergoing trials. The aim of ART has shifted from avoiding mortality and morbidity to achieving a normal life expectancy and quality of life, minimizing toxicities and preventing early cancers and age-related illnesses.

Chronic HCV infection: epidemiological and clinical relevance

Hepatitis C virus (HCV), first recognized as a cause of transfusion-associated acute and chronic hepatitis in 1989, plays a major role as a cause of chronic liver injury, with potential for neoplastic degeneration. It is mainly transmitted by the parenteral route. However, although with lower efficiency, it may be also transmitted by sexual intercourses and by the mother-to-child route. Epidemiological evidence shows that a wave of infection occurred in the 1945-65 period (baby boomers) in western countries. After acute infection, as many as 50-85% of the patients fail to clear the virus resulting in chronic liver infection and/or disease. It is estimated that, on a global scale, about 170 million people are chronically infected with HCV, leading to about 350.000 deaths yearly. Among western countries southern Europe, and particularly Italy, is among the most affected areas. The impact on the public health systems is noteworthy, with high number of hospitalizations due to chronic liver disease, cirrhosis or hepatocellular carcinoma. While waiting for a safe and effective vaccine to be made available, new promising direct-acting antiviral (DAA) drugs offer a better therapeutic scenario than in the past even for the poor responder genotypes 1 and 4, provided that effective screening and care is offered. However, the long and aspecific prodromic period before clinical symptoms develop is a major obstacle to early detection and treatment. Effective screening strategies may target at-risk groups or age specific groups, as recently recommended by the CDC.

Differences in HCV viral decline between low and standard-dose pegylated-interferon-alpha-2a with ribavirin in HIV/HCV genotype 3 patients

Background

The aim of the study was to analyze the different impact of standard and low-dose Peg-IFN-α2a/RBV therapies on HCV viral decline in HIV/HCV genotype 3 co-infected patients during the first weeks of treatment.

Methods

Plasma HCV viral decline was analyzed between baseline and weeks 1, 2 and 4 in two groups of treatment-naïve HCV genotype 3 patients with HIV co-infection. The Standard Dose Group (SDG) included patients who received Peg-IFN at 180 µg/per week with a weight-adjusted dose of ribavirin; Low-Dose Group (LDG) patients received Peg-IFN at 135 µg/per week with 800 mg/day ribavirin. The effect of IL28B genotype on HCV viral decline was evaluated in both groups. HCV viral decline was analyzed using a multivariate linear regression model.

Results

One hundred and six patients were included: 48 patients in the SDG and 58 in the LDG. HCV viral decline for patients in the LDG was less than for those in the SDG (week 1∶1.72±0.74 log₁₀ IU/mL versus 1.78±0.67 log₁₀ IU/mL, p = 0.827; week 2∶2.3±0.89 log₁₀ IU/mL versus 3.01±1.02 log₁₀ IU/mL, p = 0.013; week 4∶3.52±1.2 log₁₀ IU/mL versus 4.09±1.1 log₁₀ IU/mL, p = 0.005). The linear regression model identified the Peg-IFN/RBV dose as an independent factor for HCV viral decline at week 4.

Conclusions

Our results showed that HCV viral decline was less for patients in the low-dose group compared to those receiving the standard dose. Until a randomized clinical trial is conducted, clinicians should be cautious about using lower doses of Peg-IFN/RBV in HIV/HCV genotype 3 co-infected patients.

HIV infection, aging, and immune function: implications for cancer risk and prevention

PURPOSE OF REVIEW

Combination antiretroviral therapy (ART) has turned HIV infection into a complex chronic disease. This article documents cancer risk among HIV-infected persons, reviews immune system effects of HIV infection in relation to cancer risk, discusses implications for cancer prevention, and suggests future research directions.

RECENT FINDINGS

There has been a shift in the cancer spectrum from AIDS-defining cancers (ADC) to non-ADC, although the burden of ADC remains high. Although a high prevalence of non-HIV cancer risk factors among HIV-infected persons contributes to cancer risk, substantial evidence has accumulated in favor of an independent association between HIV-induced immunodeficiency and elevated risk of many specific cancer types, most of viral cause, although further work is needed to disentangle immunodeficiency and smoking effects for lung cancer, and immunodeficiency and hepatitis virus effects for liver cancer. Relationships between cancer risk and two other immune system hallmarks of HIV infection, chronic inflammation, and immune dysfunction/senescence, remain poorly understood.

SUMMARY

Early, sustained ART is a crucial component of cancer prevention. Continued epidemiologic monitoring is needed to detect possible effects on cancer risk of specific ART classes or medications, long-term exposure to systemic inflammation or immune dysfunction, or earlier or more effective ART.

Global burden of hepatitis C: considerations for healthcare providers in the United States

An estimated 2%-3% of the world's population is living with hepatitis C virus (HCV) infection, and each year, >350 000 die of HCV-related conditions, including cirrhosis and liver cancer. The epidemiology and burden of HCV infection varies throughout the world, with country-specific prevalence ranging from <1% to >10%. In contrast to the United States and other developed countries, HCV transmission in developing countries frequently results from exposure to infected blood in healthcare and community settings. Hepatitis C prevention, care, and treatment programs must recognize country-specific epidemiology, which varies by setting and level of economic development. Awareness of the global epidemiology of HCV infection is important for US healthcare providers treating foreign-born patients from countries where HCV infection is endemic and for counseling patients who travel to these countries. Countries with a high burden of HCV infection also would benefit from establishing comprehensive prevention, care, and treatment programs.

HCV coinfection does not alter the frequency of regulatory T cells or CD8+ T cell immune activation in chronically infected HIV+ Chinese subjects

Regulatory T cell (Treg) is a subset of CD4(+) T cells that play a critical role in regulating the immune responses. Human immunodeficiency virus (HIV) infection is associated with T cell abnormalities and alters effector T cell function. There are a large number of patients coinfected with HIV and hepatitis C virus (HCV). Here, we evaluated the proportion of CD4(+) Treg cells expressing CD25 and FOXP3, and the status of immune activation of CD8(+) T cells in 60 Chinese patients chronically infected with HIV and/or HCV. Furthermore, we investigated the influence of highly active antiretroviral therapy (HAART) on the level of Treg cells and immune activated CD8(+) T cells. We observed that the Treg level was upregulated in HIV infection and HCV infection could not enhance this kind of upregulation significantly. The level of Treg cells was negatively correlated with CD4(+) T cell counts and positively correlated with HIV viral loads. We observed considerably elevated CD38 and HLA-DR expression in CD8(+) T cells in HIV-infected subjects but not in HCV-infected patients in comparison to that in healthy controls. There is no significant difference concerning the proportion of CD8(+) T cells expressing CD38 or HLA-DR between HIV-1-monoinfected and HIV/HCV-coinfected patients. After 12-week HAART, the proportion of Treg cells dropped, but still more than the level in healthy controls. HAART could reverse the abnormal immune activation of CD8(+) T cells. The decrease of Tregs did not alter the downregulation of HIV-1-specific CTL responses in these HIV-infected patients after HAART therapy. The level of HIV virus might be the key point for the decline of CTL responses.

Generation of a humanized mouse model with both human immune system and liver cells to model hepatitis C virus infection and liver immunopathogenesis

Establishing a small animal model that accurately recapitulates hepatotropic pathogens, including hepatitis C virus (HCV) infection and immunopathogenesis, is essential for the study of hepatitis virus-induced liver disease and for therapeutics development. This protocol describes our recently developed humanized mouse model for studying HCV and other hepatotropic infections, human immune response and hepatitis and liver fibrosis. The first 5-h stage is the isolation of human liver progenitor and hematopoietic stem cells from fetal liver. Next, AFC8 immunodeficient mice are transplanted with the isolated progenitor/stem cells. This generally takes 2 h. The transplanted mice are then treated for a month with the mouse liver apoptosis-inducing AFC8 dimerizer and left for an additional 2-month period to permit human liver and immune cell growth as well as system reconstitution and development before inoculation with HCV clinical isolates. HCV infection, human immune response and liver disease are observed with high incidence from approximately 2 months after inoculation.

Low-level HIV infection of hepatocytes

BACKGROUND

There are only limited data on whether HIV infection occurs within the liver; therefore, we explored early and late stages of the HIV life cycle in two hepatocyte cell lines--Huh7.5 and Huh7.5JFH1--as well as in primary human hepatocytes.

RESULTS

Integrated HIV DNA was detected in Huh7.5 and Huh7.5JFH1 cells, as well as in primary hepatocytes, and was inhibited by the integrase inhibitor raltegravir in a dose-dependent manner. HIV p24 protein was also detected in cell culture supernatants at days 1, 3, 5, and 7 post-infection and was inhibited by AZT, although levels were modest compared to those in a lymphocyte cell line. Culture supernatants from HIV-infected hepatocytes were capable of infecting a non-hepatic HIV indicator cell line.

CONCLUSIONS

These results indicating low-level HIV replication in hepatoctyes in vitro complement evidence suggesting that HIV has deleterious effects on the liver in vivo.

Hepatitis C viral load, genotype 3 and interleukin-28B CC genotype predict mortality in HIV and hepatitis C-coinfected individuals

OBJECTIVE

We hypothesized that hepatitis C virus (HCV) load and genotype may influence all-cause mortality in HIV-HCV-coinfected individuals.

DESIGN AND METHODS

Observational prospective cohort study. Mortality rates were compared in a time-updated multivariate Poisson regression analysis.

RESULTS

We included 264 consecutive HIV-HCV-coinfected individuals. During 1143 person years at risk (PYR) 118 individuals died [overall mortality rate 10 (95% confidence interval; 8, 12)/100 PYR]. In multivariate analysis, a 1 log increase in HCV viral load was associated with a 30% higher mortality risk [adjusted mortality rate ratio (aMRR): 1.30 (1.10,1.54)] when adjusted for sex, age, HIV exposure group, CD4 cell count, HIV RNA, HCV genotype and interleukin (IL)-28B genotype. Further, HCV genotype 3 vs. 1 [aMRR: 1.83 (1.12, 2.98)] and HIV RNA [aMRR: 3.14 (1.37,7.17) for undetectable vs. just detectable HIV RNA] were independent predictors of mortality, whereas a higher CD4 cell count was associated with a 41% reduction in mortality rate per 50 cell increase between 0 and 200 cells/μl [aMRR: 0.59 (0.48, 0.72)] and a 10% reduction for increases above 200 cells/μl [aMRR: 0.90 (0.82-0.98)]. IL28B) CC genotype was associated with 54% higher mortality risk [aMRR: 1.54 (0.89, 3.82] compared to TT genotype.

CONCLUSION

High-HCV viral load, HCV genotype 3 and IL28B genotype CC had a significant influence on the risk of all-cause mortality among individuals coinfected with HIV-1. This may have consequences for the management of HIV-HCV-coinfected individuals.

Silibinin inhibits HIV-1 infection by reducing cellular activation and proliferation

Purified silymarin-derived natural products from the milk thistle plant (Silybum marianum) block hepatitis C virus (HCV) infection and inhibit T cell proliferation in vitro. An intravenous formulation of silibinin (SIL), a major component of silymarin, displays anti-HCV effects in humans and also inhibits T-cell proliferation in vitro. We show that SIL inhibited replication of HIV-1 in TZM-bl cells, PBMCs, and CEM cells in vitro. SIL suppression of HIV-1 coincided with dose-dependent reductions in actively proliferating CD19+, CD4+, and CD8+ cells, resulting in fewer CD4+ T cells expressing the HIV-1 co-receptors CXCR4 and CCR5. SIL inhibition of T-cell growth was not due to cytotoxicity measured by cell cycle arrest, apoptosis, or necrosis. SIL also blocked induction of the activation markers CD38, HLA-DR, Ki67, and CCR5 on CD4+ T cells. The data suggest that SIL attenuated cellular functions involved in T-cell activation, proliferation, and HIV-1 infection. Silymarin-derived compounds provide cytoprotection by suppressing virus infection, immune activation, and inflammation, and as such may be relevant for both HIV mono-infected and HIV/HCV co-infected subjects.

Anti-retroviral drugs do not facilitate hepatitis C virus (HCV) infection in vitro

An estimated 4 to 5 million people are co-infected with HIV/HCV worldwide. Recently observed outbreaks of acute HCV infection among HIV-positive men who have sex with men (MSM) have been linked to behavioral factors such as high risk sexual practices and recreational drug use. However, at the molecular level, many drugs such as glucocorticoids or cyclosporine A have been found to modulate viral replication. Thus, it is conceivable that drugs used in highly active antiretroviral therapy (HAART) may heighten susceptibility to HCV infection and contribute to the recent outbreaks. We therefore performed a comprehensive screen of antiretroviral drugs covering all available drug classes both individually and in typical combinations used during HAART to probe for direct effects on HCV cell entry, replication, new particle assembly and release. Importantly, no significant enhancement or inhibition of HCV cell entry, replication or new particle production was detected. While raltegravir and ritonavir boosted atazanavir reduce HCV replication, a tenfold reduction of HCVcc entry by the CCR5 antagonist maraviroc was observed. In conclusion, commonly used HAART agents do not specifically enhance HCV replication. Thus recent epidemic outbreaks of acute HCV in HIV-infected MSM are unlikely to be related to enhancing effects of HAART drugs.

Challenges for HCV vaccine development in HIV-HCV coinfection

It is estimated that 4-5 million HIV-infected patients are coinfected with HCV. The impact of HIV on the natural course of HCV infection is deleterious. This includes a higher rate of HCV persistence and a faster rate of fibrosis progression. Coinfected patients show poor treatment outcome following standard HCV therapy. Although direct antiviral agents offer new therapeutic options, their use is hindered by potential drug interactions and toxicity in HIV-infected patients under HAART. Overtime, a large reservoir of HCV genotype 1 patients will accumulate in resource poor countries where the hepatitis C treatment is not easily affordable and HIV therapy remains the primary health issue for coinfected individuals. HCV vaccines represent a promising strategy as an adjunct or alternative to current HCV therapy. Here, the authors review the pathogenesis of hepatitis C in HIV-infected patients, with a focus on the impact of HIV on HCV-specific immune responses and discuss the challenges for vaccine development in HIV-HCV coinfection.

HIV-coinfection leads to a modest increase in plasma HCV-RNA load in patients with chronic HCV infection

The influence of HIV coinfection on plasma hepatitis C virus (HCV) RNA load has not been reliably evaluated. We analyzed plasma HCV RNA load in 396 HCV-monoinfected and 467 HIV/HCV-coinfected patients. Median HCV RNA concentrations (interquartile range) in HCV-monoinfected patients were 5.88 (5.3-6.2) log(10)IU/mL versus 5.96 (5.6-6.5) log(10)IU/mL in HIV/HCV-coinfected individuals (p=0.033) as determined with the Cobas Amplicor Test and 6.06 (5.4-5.7) log(10)IU/mL versus 6.3 (5.5-6.9) log(10)IU/mL (p=0.026) using the Cobas TaqMan System. The plasma HCV RNA load in patients with HIV infection and undetectable plasmatic HIV RNA was similar to that observed in HCV-monoinfected individuals [6.02 (5.45-6.61) log(10)IU/mL versus 6.01 (5.36-6.59) log(10)IU/mL, respectively (p=1.0)]. In conclusion, HIV coinfection tends to be associated with higher plasma HCV RNA load, however, the magnitude of the differences is small and this effect can be counterbalanced with antiviral therapy.

Virological effectiveness and CD4+ T-cell increase over early and late courses in HIV infected patients on antiretroviral therapy: focus on HCV and anchor class received

Background

The aim of this study was to explore the effects of HCV co-infection on virological effectiveness and on CD4+ T-cell recovery in patients with an early and sustained virological response after HAART.

Methods

We performed a longitudinal analysis of 3,262 patients from the MASTER cohort, who started HAART from 2000 to 2008. Patients were stratified into 6 groups by HCV status and type of anchor class. The early virological outcome was the achievement of HIV RNA <500 copies/ml 4–8 months after HAART initiation. Time to virological response was also evaluated by Kaplan-Meier analysis. The main outcome measure of early immunological response was the achievement of CD4+ T-cell increase by ≥100/mm³ from baseline to month 4–8 in virological responder patients. Late immunological outcome was absolute variation of CD4+ T-cell count with respect to baseline up to month 24. Multivariable analysis (ANCOVA) investigated predictors for this outcome.

Results

The early virological response was higher in HCV Ab-negative than HCV Ab-positive patients prescribed PI/r (92.2% versus 88%; p = 0.01) or NNRTI (88.5% versus 84.7%; p = 0.06). HCV Ab-positive serostatus was a significant predictor of a delayed virological suppression independently from other variables, including types of anchor class. Reactivity for HCV antibodies was associated with a lower probability of obtaining ≥100/mm³ CD4+ increase within 8 months from HAART initiation in patients treated with PI/r (62.2% among HCV Ab-positive patients versus 70.9% among HCV Ab-negative patients; p = 0.003) and NNRTI (63.7% versus 74.7%; p < 0.001). Regarding late CD4+ increase, positive HCV Ab appeared to impair immune reconstitution in terms of absolute CD4+ T-cell count increase both in patients treated with PI/r (p = 0.013) and in those treated with NNRTI (p = 0.002). This was confirmed at a multivariable analysis up to 12 months of follow-up.

Conclusions

In this large cohort, HCV Ab reactivity was associated with an inferior virological outcome and an independent association between HCV Ab-positivity and smaller CD4+ increase was evident up to 12 months of follow-up. Although the difference in CD4+ T-cell count was modest, a stricter follow-up and optimization of HAART strategy appear to be important in HIV patients co-infected by HCV. Moreover, our data support anti-HCV treatment leading to HCV eradication as a means to facilitate the achievement of the viro-immunological goals of HAART.

Review and management of drug interactions with boceprevir and telaprevir

Boceprevir (BOC) and telaprevir (TPV), when added to pegylated interferon and ribavirin for the treatment of chronic hepatitis C virus (HCV) infection, increase the rates of sustained virologic response in treatment-naïve persons to approximately 70%. Though these agents represent an important advance in the treatment of chronic HCV, they present new treatment challenges to the hepatology community. BOC and TPV are both substrates and inhibitors of the hepatic enzyme, cytochrome P450 3A, and the drug transporter, P-glycoprotein, which predisposes these agents to many drug interactions. Identification and appropriate management of potential drug interactions with TPV and BOC is critical for optimizing therapeutic outcomes during hepatitis C treatment. This review highlights the pharmacologic characteristics and drug-interaction potential of BOC and TPV and provides guidance on the management of drug interactions with these agents.

Crosstalk between HIV and hepatitis C virus during co-infection

An estimated one-third of individuals positive for HIV are also infected with hepatitis C virus (HCV). Chronic infection with HCV can lead to serious liver disease including cirrhosis and hepatocellular carcinoma. Liver-related disease is among the leading causes of death in patients with HIV, and individuals with HIV and HCV co-infection are found to progress more rapidly to serious liver disease than mono-infected individuals. The mechanism by which HIV affects HCV infection in the absence of immunosuppression by HIV is currently unknown. In a recent article published in BMC Immunology, Qu et al. demonstrated that HIV tat is capable of inducing IP-10 expression. Further, they were able to show that HIV tat, when added to cells, was able to enhance the replication of HCV. Importantly, the increase in HCV replication by tat was found to be dependent on IP-10. This work has important implications for understanding the effect HIV has on the outcome of HCV infection in co-infected individuals. The findings of Qu et al. may inform the design of intervention and treatment strategies for co-infected individuals.Please see related article: http://www.biomedcentral.com/1471-2172/13/15.

Chronic hepatitis C treatment outcomes in low- and middle-income countries: a systematic review and meta-analysis

OBJECTIVE

To assess the effectiveness of treatment for hepatitis C virus (HCV) infection in low- and middle-income countries and identify factors associated with successful outcomes.

METHODS

We performed a systematic review and meta-analysis of studies of HCV treatment programmes in low- and middle-income countries. The primary outcome was a sustained virological response (SVR). Factors associated with treatment outcomes were identified by random-effects meta-regression analysis.

FINDINGS

The analysis involved data on 12 213 patients included in 93 studies from 17 countries. The overall SVR rate was 52% (95% confidence interval, CI: 48-56). For studies in which patients were predominantly infected with genotype 1 or 4 HCV, the pooled SVR rate was 49% (95% CI: 43-55). This was significantly lower than the rate of 59% (95% CI: 54-64) found in studies in which patients were predominantly infected with other genotypes (P = 0.012). Factors associated with successful outcomes included treatment with pegylated interferon and ribavirin, infection with an HCV genotype other than genotype 1 or 4 and the absence of liver damage or human immunodeficiency virus infection at baseline. No significant difference in the SVR rate was observed between weight-adjusted and fixed-dose ribavirin treatment. Overall, 17% (95% CI: 13-23) of adverse events resulted in treatment interruption or dose modification, but only 4% (95% CI: 3-5) resulted in treatment discontinuation.

CONCLUSION

The outcomes of treatment for HCV infection in low- and middle-income countries were similar to those reported in high-income countries.

Substance Abuse, Hepatitis C, and Aging in HIV: Common Cofactors that Contribute to Neurobehavioral Disturbances

Although the prevalence of neurocognitive disturbances among individuals with HIV has decreased in recent years, rates of impairment still remain high. This review presents findings from comorbid conditions that may contribute to further neurocognitive impairments in this already vulnerable population. We will focus on three co-factors that have received substantial attention in the neuroAIDS literature: drug use, hepatitis C co-infection (HCV), and aging. All three conditions commonly co-occur with HIV and likely interact with HIV in complex ways. Collectively, the extant literature suggests that drug use, HCV, and aging serve to worsen the neurocognitive profile of HIV through several overlapping mechanisms. A better understanding of how specific comorbidities interact with HIV may reveal specific phenotypes of HIV-associated neurocognitive disorder that may aid in the development of more targeted behavioral and pharmacological treatment efforts.