Human Immunodeficiency Virus Co-infected Patients Research Articles

Therapy of Hepatitis C: From Empiricism to Eradication

The complications of chronic hepatitis C virus infection can be prevented by antiviral therapy. The initial choice of interferon alfa and, subsequently, ribavirin as potential treatments for chronic hepatitis C was empirical. Nevertheless, the combination of pegylated interferon alfa and ribavirin has become the standard treatment of chronic hepatitis C. Since the advent of interferon-based therapy, enormous progress has been made in understanding the mechanisms of treatment efficacy and failure, and in everyday patient management. The principal advances are: a better understanding of hepatitis C virus steady-state kinetics and the antiviral mechanisms of interferon and ribavirin; easier treatment decisions thanks to novel assays to assess liver disease severity and the virological characteristics of infection; a better use of virological tests to tailor therapy; a better management of adverse effects; a better understanding of virological treatment failure; and a better management of "special" populations, including patients with decompensated cirrhosis and end-stage liver disease, liver transplant recipients, hemodialysis patients and renal transplant recipients, human immunodeficiency virus-coinfected patients, intravenous drug users and patients on opiate replacement therapy, or virological non responders to previous therapies. Steady-state HCV kinetics offers several potential targets for new drugs. These targets should ideally be hit simultaneously in order to achieve viral eradication within a reasonable time frame. Future drugs for HCV infection will belong to four main categories, including new interferons, alternatives to ribavirin, specific HCV inhibitors, and immune modulators. New treatments and vaccines might make it possible to eradicate HCV in the future.

Predictive factors of lopinavir/ritonavir discontinuation for drug-related toxicity: results from a cohort of 416 multi-experienced HIV-infected individuals

The objective of this study was to find predictive factors of lopinavir/ritonavir (LPV/r) discontinuation for drug-related toxicities in highly pre-treated human immunodeficiency virus (HIV)-infected subjects. The study was an observational study of HIV patients starting LPV/r with HIV RNA >3 log 10 copies/mL and a follow-up ≥6 months. Parameters studied were HIV RNA, CD4+ cell counts, metabolic parameters and drug-related adverse events. Acquired immune deficiency syndrome (AIDS) events and deaths were recorded. The Kaplan–Meier (KM) model was used to estimate time-dependent probability, and the multivariable Cox model to identify predictors of LPV/r discontinuation for adverse events. The study evaluated 416 HIV-infected patients. Seventy-seven patients (18.5%) discontinued LPV/r for toxicities. Adverse events leading to LPV/r discontinuation were gastrointestinal symptoms in 40 cases, hyperlipidaemia in 27 and increase of aspartate aminotransferase (AST)/alanine aminotransferase (ALT) in 10 patients. Nineteen patients (4.6%) developed an AIDS event during observation and 15 (3.6%) died. The KM probability of LPV/r discontinuation for toxicities was 5.3% (range 3.1–7.5%) at month 12 and 15.7% (range 12.1–19.3%) at month 24. Subjects with hepatitis C virus (HCV)–HIV co-infection (odds ratio (OR) 7.40; 95% confidence interval (CI) 3.73–14.66 versus HCV-negative; P = 0.001) and receiving LPV/r plus nucleoside reverse transcriptase inhibitors (NRTIs) and protease inhibitor (PI)/non-nucleoside reverse transcriptase inhibitor (NNRTI) (OR 1.74; 95% CI 1.04–2.91 versus LPV/r plus only NRTIs; P = 0.04) showed a higher risk of LPV/r discontinuation by a Cox analysis, whereas non-intravenous drug abusers (IVDUs) (OR 0.40; 95% CI 0.24–0.67 versus IVDUs; P = 0.001) had a lower risk. The rate of discontinuation for toxicity decreased by 17% for each additional month of LPV/r exposure (OR 0.83; 95% CI 0.80–0.86 for each additional month; P < 0.001). LPV/r was substantially well tolerated. Diarrhoea was the most frequent adverse event leading to discontinuation. HCV–HIV co-infected patients and patients with a short exposure to LPV/r have a higher risk of discontinuing LPV/r and should be strictly monitored.

Hepatitis B virus and human immunodeficiency virus co‐infection in sub‐Saharan Africa: a call for further investigation

A growing body of evidence indicates that human immunodeficiency virus (HIV)-positive individuals are more likely to be infected with hepatitis B virus (HBV) than HIV-negative individuals, possibly as a result of shared risk factors. There is also evidence that HIV-positive individuals who are subsequently infected with HBV are more likely to become HBV chronic carriers, have a high HBV replication rate, and remain hepatitis Be antigen positive for a much longer period. In addition, it is evident that immunosuppression brought about by HIV infection may cause reactivation or reinfection in those previously exposed to HBV. Furthermore, HIV infection exacerbates liver disease in HBV co-infected individuals, and there is an even greater risk of liver disease when HIV and HBV co-infected patients are treated with highly active anti-retroviral therapy (HAART). Complicating matters further, there have been several reports linking HIV infection to 'sero-silent' HBV infections, which presents serious problems for diagnosis, prevention, and control. In sub-Saharan Africa, where both HIV and HBV are endemic, little is known about the burden of co-infection and the interaction between these two viruses. This paper reviews studies that have investigated HIV and HBV co-infection in sub-Saharan Africa, against a backdrop of what is currently known about the interactions between these two viruses.

GB virus C genotype determination in GB virus-C/HIV co-infected individuals.

Several recent studies have indicated that patients infected with human immunodeficiency virus (HIV) exhibit a beneficial effect of co-infection with GB virus C (GBV-C). The benefit is demonstrated by slower progression to acquired immunodeficiency syndrome (AIDS) and prolonged survival time after the development of AIDS. In some but not all studies, a significant association between GBV-C/HIV co-infection and increased CD4(+) cell counts has been reported. To understand further the possible role that GBV-C might play in the reduced morbidity and mortality among HIV-infected patients, we sought to examine the presence of different GBV-C genotypes in a cohort of co-infected patients. PCR products derived from the 5'-untranslated region (5'-UTR) and the second envelope gene (E2) were sequenced directly and genotyped by phylogenetic analysis. While 5'-UTR analysis delineated the major type, analysis of the complete E2 gene was required for identification of group 2 subtypes, designated 2a and 2b. Among 35 patients tested, GBV-C genotype was determined for 33: two patients were infected with genotype 1, 12 with type 2a, and 19 with type 2b. Clinical data were available for 25 genotyped patients: one infected with genotype 1, nine with genotype 2a, and 15 with type 2b. CD4 cell counts tended to be lower in patients infected with genotype 2a compared with those with genotype 2b (310 +/- 136 vs 430 +/- 199, P = 0.054). Additional studies with larger cohorts from separate geographical regions are needed to determine whether a particular GBV-C genotype is associated with reduced morbidity or mortality among HIV co-infected patients.

Molecular epidemiology of Leishmania infantum on the island of Majorca: a comparison of phenotypic and genotypic tools

In the Mediterranean basin, Leishmania infantum is the causative agent of both visceral and cutaneous leishmaniasis, and is an important opportunistic parasite in patients infected with human immunodeficiency virus (HIV). The commonest method used to study the variability of Leishmania spp. is isoenzyme analysis. In addition to this, we employed 3 assays based on the polymerase chain reaction (PCR): random amplified polymorphic deoxyribonucleic acid (RAPD), intergenic region typing (IRT), based on the amplification of ribosomal ribonucleic acid internal transcribed spacers and restriction fragment length polymorphism (PCR-RFLP). We used 54 L. infantum stocks isolated from HIV co-infected patients, 38 isolated from dogs, 3 isolated from immunocompetent patients and 3 isolated from 1826 sand flies in the island of Majorca (Spain), a closed ecological niche. Zymodemes MON-1 (70%), MON-24 (11%) and MON-34 (18%) were found among the human isolates, and MON-1 (95%) and MON-108 (5%) among those from dogs. RAPD and IRT could not discriminate among the strains as they all gave the same pattern, even when different zymodemes were examined. In contrast, PCR-RFLP was able to distinguish the strains and, furthermore, a dendrogram (unweighted pair group method with arithmetic average [UPGMA]) was constructed from the genetic distances derived from RFLP data. The Leishmania isolates from HIV-infected subjects formed a single cluster, supporting the existence of an artificial anthroponotic cycle previously proposed by our group, in which syringes have been substituted for sand flies, and in which certain clones have been spread among intravenous drug users. This contrasts with the clusters representing a zoonotic cycle, involving dogs, sand flies and both immunocompetent and immunocompromised humans.

Influence of CD4 cell counts on the genetic heterogeneity of hepatitis C virus in patients coinfected with human immunodeficiency virus.

To study the effects of reduced CD4 T cell activity on hepatitis C virus (HCV) genetic heterogeneity, HCV quasi-species complexity and diversification over time were analyzed for 56 human immunodeficiency virus-coinfected patients. Patients were selected retrospectively from the French Seroconverter Cohort (SEROCO) and the French Hemophilia Cohort (HEMOCO) for having stable CD4 cell counts for 3 years. HCV complexity was assessed by single-strand conformation polymorphism analysis of the envelope-coding region (HVR) and the core region at 2 time points 3 years apart. Increased HVR complexity was associated with higher CD4 cell count and HCV genotype 1 infection. Qualitative variation of HVR and core region was not related to CD4 cell count and depended on the initial complexity. Complexity of both regions remained unchanged over 3 years. Among these HCV-HIV-coinfected patients with stable CD4 cell counts, viral genotype and CD4 cell count may have influenced HVR complexity before their inclusion in the study but were not involved in HVR diversification during the 3-year follow-up period.

Hepatitis c virus and human immunodeficiency virus: clinical issues in coinfection

The prevalence of hepatitis C virus (HCV) and human immunodeficiency virus (HIV) coinfection ranges from nearly 30% to over 50%, depending on the population. Shared modes of transmission and the success of current antiretroviral regimens have contributed to the emergence of HCV as a significant pathogen in the HIV-positive population. HIV coinfection appears to worsen HCV infection, with studies showing more severe fibrosis, a higher frequency of cirrhosis, and increased deaths from liver disease. HIV coinfection may also increase the rate of maternal-fetal transmission of HCV. Similarly, studies suggest a more rapid progression to AIDS or death for HCV genotypes 1a and 1b than for other genotypes in HIV-infected patients with hemophilia. Highly active antiretroviral therapy (HAART), such as HIV protease inhibitors, has no effect on HCV infection and may transiently increase ALT, AST, and hepatitis C viral load. Hepatotoxicity associated with HAART may or may not be related to the presence of HCV and may depend on the specific agents used. Data suggest that treating chronic hepatitis C in HIV–co-infected patients can decrease fibrosis, increase T-cell responsiveness to HCV antigens, and decrease the rate of fatal hepatomas. Interferon α may provide sustained biochemical or virologic responses in HIV/HCV-coinfected patients. The combination of interferon-α and ribavirin may also be a treatment option but is more complex, and additional research is needed. Treating HCV infection in HIV/HCV-coinfected individuals may help lower the hepatitis C viral load and permit treatment with protease inhibitors.

Hepatitis C in human immunodeficiency virus-coinfected patients: Increased variability in the hypervariable envelope coding domain

Patients coinfected with the hepatitis C virus (HCV) and the human immunodeficiency virus (HIV) were studied with regard to nucleotide sequence variability in the E2/NS1 first hypervariable region of the HCV genome. The nucleotide variability within individual patients was compared to patients infected only with HCV. The proportion of predicted synonymous and nonsynonymous amino acid changes, and the relationship to putative high-antigenicity sites, were evaluated in the hypervariable envelope domain. Ninety-one clones from 10 patients with HCV/HIV coinfection were sequenced, following polymerase chain reaction (PCR) amplification of the hypervariable region. The control HCV group included 53 clones from 7 patients. Sequence analysis encompassed the region coding for amino acids 384 to 414. Consensus sequences from each patient were used as the internal standard for nonsynonymous amino acid codon variability. Cumulative proportional comparison at each amino acid site revealed increased variability in HCV RNA from patients with HCV/HIV coinfection versus HCV alone (P < .05). The greatest variability was observed at amino acids 386, 397, 400, 402, 405, 407, and 414, with >l0 percent clonal variation at these sites. Jameson-Wolf plots were used to predict putative high-antigenicity domains. Nonsynonymous clonal variation resulted in alteration of putative antigenic sites within the hypervariable region. All clones had at least one high-probability site. Clones with unique predicted antigenic domains were observed more frequently in HIV/HCV coinfected patients, and, independent of viral titer, were consistent with increased sequence variability. These data suggest an accumulation of envelope variants in the HCV/HIV coinfected patients, which could be related to ineffective viral clearance, and may help explain prior reports of interferon (IFN) resistance in this patient group.

Hepatitis C in human immunodeficiency virus-coinfected patients: Increased variability in the hypervariable envelope coding domain

Patients coinfected with the hepatitis C virus (HCV) and the human immunodeficiency virus (HIV) were studied with regard to nucleotide sequence variability in the E2/NS1 first hypervariable region of the HCV genome. The nucleotide variability within individual patients was compared to patients infected only with HCV. The proportion of predicted synonymous and nonsynonymous amino acid changes, and the relationship to putative high-antigenicity sites, were evaluated in the hypervariable envelope domain. Ninety-one clones from 10 patients with HCV/HIV coinfection were sequenced, following polymerase chain reaction (PCR) amplification of the hypervariable region. The control HCV group included 53 clones from 7 patients. Sequence analysis encompassed the region coding for amino acids 384 to 414. Consensus sequences from each patient were used as the internal standard for nonsynonymous amino acid codon variability. Cumulative proportional comparison at each amino acid site revealed increased variability in HCV RNA from patients with HCV/HIV coinfection versus HCV alone (P < .05). The greatest variability was observed at amino acids 386, 397, 400, 402, 405, 407, and 414, with >l0 percent clonal variation at these sites. Jameson-Wolf plots were used to predict putative high-antigenicity domains. Nonsynonymous clonal variation resulted in alteration of putative antigenic sites within the hypervariable region. All clones had at least one high-probability site. Clones with unique predicted antigenic domains were observed more frequently in HIV/HCV coinfected patients, and, independent of viral titer, were consistent with increased sequence variability. These data suggest an accumulation of envelope variants in the HCV/HIV coinfected patients, which could be related to ineffective viral clearance, and may help explain prior reports of interferon (IFN) resistance in this patient group. (Hepatology 1996 Apr;23(4):688-94)