Bernd Kupfer

Effect of antiretroviral therapy on liver-related mortality in patients with HIV and hepatitis C virus coinfection

BACKGROUND Highly active antiretroviral therapy (HAART) has improved the prognosis of HIV infection. However, replication of hepatitis C virus (HCV) is not inhibited by HAART, and treatment-related hepatotoxicity is common. To clarify the effect of HAART in HIV/HCV-coinfected patients, we studied liver-related mortality and overall mortality in 285 patients who were regularly treated during the period 1990-2002 at our department. METHODS Survival was analysed retrospectively by Kaplan-Meier and Coxs regression analyses after patients (81% haemophiliacs) had been stratified into three groups according to their antiretroviral therapy (HAART n=93, available after 1995; treatment exclusively with nucleoside analogues n=55, available after 1992; or no treatment, n=137). FINDINGS Liver-related mortality rates were 0.45, 0.69, and 1.70 per 100 person-years in the HAART, antiretroviral-treatment, and untreated groups. Kaplan-Meier analysis of liver-related mortality confirmed the significant survival benefit in patients with antiretroviral therapy (p=0.018), and regression analysis identified HAART (odds ratio 0.106 [95% CI 0.020-0.564]), antiretroviral treatment (0.283 [0.103-0.780]), CD4-positive T-cell count (0.746 [0.641-0.868] per 0.05x10(9) cells/L), serum cholinesterase (0.962 [0.938-0.986] per 100 U/L), and age (1.065 [1.027-1.105] per year) as independent predictors of liver-related survival. Severe drug-related hepatotoxicity was seen in five patients treated with nucleoside analogues alone and 13 treated with HAART. No patient died from drug-related hepatotoxicity. INTERPRETATION In addition to improved overall survival, antiretroviral therapy significantly reduced long-term liver-related mortality in our patients. This survival benefit seems to outweigh by far the associated risks of severe hepatotoxicity.

Human Bocavirus: Passenger or Pathogen in Acute Respiratory Tract Infections?

SUMMARY Human bocavirus (HBoV) is a newly identified virus tentatively assigned to the family Parvoviridae, subfamily Parvovirinae, genus Bocavirus. HBoV was first described in 2005 and has since been detected in respiratory tract secretions worldwide. Herein we review the literature on HBoV and discuss the biology and potential clinical impact of this virus. Most studies have been PCR based and performed on patients with acute respiratory symptoms, from whom HBoV was detected in 2 to 19% of the samples. HBoV-positive samples have been derived mainly from infants and young children. HBoV DNA has also been detected in the blood of patients with respiratory tract infection and in fecal samples of patients with diarrhea with or without concomitant respiratory symptoms. A characteristic feature of HBoV studies is the high frequency of coinciding detections, or codetections, with other viruses. Available data nevertheless indicate a statistical association between HBoV and acute respiratory tract disease. We present a model incorporating these somewhat contradictory findings and suggest that primary HBoV infection causes respiratory tract symptoms which can be followed by prolonged low-level virus shedding in the respiratory tract. Detection of the virus in this phase will be facilitated by other infections, either simply via increased sample cell count or via reactivation of HBoV, leading to an increased detection frequency of HBoV during other virus infections. We conclude that the majority of available HBoV studies are limited by the sole use of PCR diagnostics on respiratory tract secretions, addressing virus prevalence but not disease association. The ability to detect primary infection through the development of improved diagnostic methods will be of great importance for future studies seeking to assign a role for HBoV in causing respiratory illnesses.

Spontaneous Viral Clearance, Viral Load, and Genotype Distribution of Hepatitis C Virus (HCV) in HIV-Infected Patients with Anti-HCV Antibodies in Europe

BACKGROUND Variables influencing serum hepatitis C virus (HCV) RNA levels and genotype distribution in individuals with human immunodeficiency virus (HIV) infection are not well known, nor are factors determining spontaneous clearance after exposure to HCV in this population. METHODS All HCV antibody (Ab)-positive patients with HIV infection in the EuroSIDA cohort who had stored samples were tested for serum HCV RNA, and HCV genotyping was done for subjects with viremia. Logistic regression was used to identify variables associated with spontaneous HCV clearance and HCV genotype 1. RESULTS Of 1940 HCV Ab-positive patients, 1496 (77%) were serum HCV RNA positive. Injection drug users (IDUs) were less likely to have spontaneously cleared HCV than were homosexual men (20% vs. 39%; adjusted odds ratio [aOR], 0.36 [95% confidence interval {CI}, 0.24-0.53]), whereas patients positive for hepatitis B surface antigen (HBsAg) were more likely to have spontaneously cleared HCV than were those negative for HBsAg (43% vs. 21%; aOR, 2.91 [95% CI, 1.94-4.38]). Of patients with HCV viremia, 786 (53%) carried HCV genotype 1, and 53 (4%), 440 (29%), and 217 (15%) carried HCV genotype 2, 3, and 4, respectively. A greater HCV RNA level was associated with a greater chance of being infected with HCV genotype 1 (aOR, 1.60 per 1 log higher [95% CI, 1.36-1.88]). CONCLUSIONS More than three-quarters of the HIV- and HCV Ab-positive patients in EuroSIDA showed active HCV replication. Viremia was more frequent in IDUs and, conversely, was less common in HBsAg-positive patients. Of the patients with HCV viremia analyzed, 53% were found to carry HCV genotype 1, and this genotype was associated with greater serum HCV RNA levels.

Interferon-lambda serum levels in hepatitis C

BACKGROUND & AIMS Dendritic cells (DCs) trigger adaptive immune responses and are an important source of antiviral cytokines. In hepatitis C virus (HCV) infection DC function is markedly impaired. Thus far, studies have focused on types I and II interferon (IFN). We studied IFN-lambda1 (IL-29) and IFN-lambda2/3 (IL-28A/B) serum levels in patients with different outcomes of HCV infection. METHODS IFN-lambdas were measured by ELISAs detecting IL-29 or IL-28A and IL-28B, respectively. Results were stratified with respect to the recently discovered rs12979860 T/C polymorphism upstream of the IL-28B gene. RESULTS In general IL-29 serum levels exceeded IL-28A/B at least twofold, with IL-29 and IL-28A/B levels being significantly higher in carriers of the rs12979860 C allele than in TT homozygous individuals (p<0.02). IL-29 levels were substantially lower in patients with chronic hepatitis C than in healthy controls (p=0.005) and patients with spontaneously resolved hepatitis (p=0.001). Patients with acute hepatitis C showed IL-29 levels intermediate between chronic hepatitis C and normal controls; and IL-29 serum levels were higher in patients who spontaneously resolved hepatitis C than in those who became chronic. In vitro HCV proteins NS3 and E2 directly inhibited IL-29 production in poly I:C-stimulated purified DCs. CONCLUSIONS Our data suggest that HCV proteins modify IFN-lambda production in DCs. Carriers of the rs12979860 C allele associated with resolution of HCV infection exhibited increased IFN-lambda levels. Moreover, high IFN-lambda levels predisposed to spontaneous resolution of HCV infection. Thus, IFN-lambdas seem to play an important role in the control of hepatitis C.

Reactivation of hepatitis B in a long-term anti-HBs-positive patient with AIDS following lamivudine withdrawal

BACKGROUND/AIMS In HIV-infected patients, who have recovered completely from an acute hepatitis B infection and become anti-HBs positive, hepatitis B infection may be reactivated after progression to AIDS. CASE REPORT We present the case of a homosexual male patient with AIDS who developed clinical and serological reactivation of hepatitis B with detectable HBV-DNA 18 years after complete recovery from acute hepatitis B infection. Prior to reactivation, antiretroviral triple therapy including lamivudine was changed to therapy without lamivudine. After reintroduction of lamivudine in the triple therapy, HBV-DNA became undetectable and the patient lost HBsAg and again developed anti-HBs antibodies. CONCLUSION The hepatitis B in this patient can be explained best by reactivation of persistent HBV infection, possibly because of transient decline in antibodies against HBs-antigen due to a reduction in CD4+ lymphocyte numbers and B cell dysfunction. This observation points to the clinical relevance of HBV persistence in serum and blood cells of anti-HBs-positive subjects for many years after recovery from acute hepatitis B infection. The possible role of lamivudine withdrawal which immediately preceded HBV breakthrough in our patient is noteworthy. Regular monitoring of markers of HBV infection, including HBV-DNA, in patients with AIDS appears justified after discontinuation of lamivudine.

Computational methods for the design of effective therapies against drug resistant HIV strains

The development of drug resistance is a major obstacle to successful treatment of HIV infection. The extraordinary replication dynamics of HIV facilitates its escape from selective pressure exerted by the human immune system and by combination drug therapy. We have developed several computational methods whose combined use can support the design of optimal antiretroviral therapies based on viral genomic data.

Prospective study of Human Bocavirus (HBoV) infection in a pediatric university hospital in Germany 2005/2006

Abstract Background Human Bocavirus (HBoV), a new species of the genus parvovirus newly detected in 2005, seems to be a worldwide distributed pathogen among children with respiratory tract infection (prevalence 2%–18%). Recently published retrospective studies and one prospective birth cohort study suggest that HBoV-primary infection occurs in infants. Methods Prospective single center study over one winter season (November 2005–May 2006) with hospitalized children without age restriction using PCR-based diagnostic methods. Results HBoV DNA was detected in 11 (2.8%) of 389 nasopharyngeal aspirates from symptomatic hospitalized children (median age 9.0 months; range: 3–17 months). RSV, HMPV, HCoV, and Influenza B were detected in 13.9% (n =54), 5.1% (n =20), 2.6% (n =10), and 1.8% (n =7), respectively. There was no influenza A DNA detected in any of the specimens. The clinical diagnoses were acute wheezing (bronchitis) in four patients, radiologically confirmed pneumonia in six patients (55%) and croup syndrome in one patient. In five to six patients with pneumonia, HBoV was the only pathogen detected. While no patient had to be mechanically ventilated, 73% needed oxygen supplementation. In four (36.4%) patients at least one other viral pathogen was found (plus RSV n =3; 27.3%; Norovirus n =1; 9.1%). Conclusion HBoV causes severe respiratory tract infections in infants and young children. Its role as a copathogen and many other open questions has to be defined in further prospective studies.

Frequent hepatitis B virus rebound among HIV-hepatitis B virus-coinfected patients following antiretroviral therapy interruption.

Background:The impact of antiretroviral therapy (ART) interruption in HIV–hepatitis B virus (HBV)-coinfected patients was examined in the Strategic Management of AntiRetroviral Therapy (SMART) study. Methods:Plasma HBV DNA was measured in all hepatitis B surface antigen-positive (HBV-positive) participants at baseline, and at months 1, 2, 4, 6, 8, 10, and 12. Results:Among HBV-positive participants in the ART interruption (drug conservation) (n = 72) and ART continuation (virological suppression) (n = 62) arms, HBV DNA rebound of more than 1 log from baseline at months 1–4 was seen in 31–33% (P = 0.003) and 3–4% (P = 0.017), respectively. Thirteen HBV-positive participants had HBV DNA rebound of more than 3 log, including 12 in the drug conservation arm, of which eight were on tenofovir-containing regimens. Factors independently associated with a HBV DNA rebound were drug conservation arm (P = 0.0002), nondetectable HBV DNA at baseline (P = 0.007), and black race (P = 0.03). Time to ART reinitiation was shorter (7.5, 15.6, and 17.8 months; P < 0.0001) and proportion reinitiating greater (62.5, 46.5, and 39.7%; P = 0.0002) among HBV-positive participants as compared with hepatitis C virus-positive and non-HBV/hepatitis C virus participants in the drug conservation arm. No hepatic decompensation events occurred among HBV-positive participants in either arm. Conclusion:HBV DNA rebound following ART interruption is common and may be associated with accelerated immune deficiency in HIV–HBV-coinfected patients.

A Novel Diagnostic Target in the Hepatitis C Virus Genome

Background Detection and quantification of hepatitis C virus (HCV) RNA is integral to diagnostic and therapeutic regimens. All molecular assays target the viral 5′-noncoding region (5′-NCR), and all show genotype-dependent variation of sensitivities and viral load results. Non-western HCV genotypes have been under-represented in evaluation studies. An alternative diagnostic target region within the HCV genome could facilitate a new generation of assays. Methods and Findings In this study we determined by de novo sequencing that the 3′-X-tail element, characterized significantly later than the rest of the genome, is highly conserved across genotypes. To prove its clinical utility as a molecular diagnostic target, a prototype qualitative and quantitative test was developed and evaluated multicentrically on a large and complete panel of 725 clinical plasma samples, covering HCV genotypes 1–6, from four continents (Germany, UK, Brazil, South Africa, Singapore). To our knowledge, this is the most diversified and comprehensive panel of clinical and genotype specimens used in HCV nucleic acid testing (NAT) validation to date. The lower limit of detection (LOD) was 18.4 IU/ml (95% confidence interval, 15.3–24.1 IU/ml), suggesting applicability in donor blood screening. The upper LOD exceeded 10−9 IU/ml, facilitating viral load monitoring within a wide dynamic range. In 598 genotyped samples, quantified by Bayer VERSANT 3.0 branched DNA (bDNA), X-tail-based viral loads were highly concordant with bDNA for all genotypes. Correlation coefficients between bDNA and X-tail NAT, for genotypes 1–6, were: 0.92, 0.85, 0.95, 0.91, 0.95, and 0.96, respectively; X-tail-based viral loads deviated by more than 0.5 log10 from 5′-NCR-based viral loads in only 12% of samples (maximum deviation, 0.85 log10). The successful introduction of X-tail NAT in a Brazilian laboratory confirmed the practical stability and robustness of the X-tail-based protocol. The assay was implemented at low reaction costs (US

Quality control assessment of human immunodeficiency virus type 2 (HIV-2) viral load quantification assays: results from an international collaboration on HIV-2 infection in 2006.

8.70 per sample), short turnover times (2.5 h for up to 96 samples), and without technical difficulties. Conclusion This study indicates a way to fundamentally improve HCV viral load monitoring and infection screening. Our prototype assay can serve as a template for a new generation of viral load assays. Additionally, to our knowledge this study provides the first open protocol to permit industry-grade HCV detection and quantification in resource-limited settings.