Ultrasensitive amplification refractory mutation system real-time PCR (ARMS RT-PCR) assay for detection of minority hepatitis B virus-resistant strains in the era of personalized medicine.

Resistance to antiviral treatment for chronic hepatitis B virus (HBV) has been associated with mutations in the HBV polymerase region. This study aimed at developing an ultrasensitive method for quantifying viral populations with all major HBV resistance-associated mutations, combining the amplification refractory mutation system real-time PCR (ARMS RT-PCR) with a molecular beacon using a LightCycler. The discriminatory ability of this method, the ARMS RT-PCR with molecular beacon assay, was 0.

Renal transplantation from hepatitis B surface antigen (HBsAg)-positive donors to HBsAg-negative recipients: a case of post-transplant fulminant hepatitis associated with an extensively mutated hepatitis B virus strain and review of the current literature.

Purpose: The purpose of this study was to present a fatal case of fulminant hepatitis B (FHB) that developed in a renal transplant recipient, immunized against hepatitis B, 1 year post transplantation.

Methods: Polymerase chain reaction amplification and full genome sequencing were performed to investigate whether specific mutations were associated with hepatitis B virus (HBV) transmission and FHB.

Results: Molecular analysis revealed multiple mutations in various open reading frames of HBV, the most important being the G145R escape mutation and a frameshift mutation-insertion (1838insA) within the pre-C/C reading frame.

Comparative evaluation of the performance of the Abbott RealTime HIV-1 assay for measurement of HIV-1 plasma viral load on genetically diverse samples from Greece.

Background: HIV-1 is characterized by increased genetic heterogeneity which tends to hinder the reliability of detection and accuracy of HIV-1 RNA quantitation assays.

Methods: In this study, the Abbott RealTime HIV-1 (Abbott RealTime) assay was compared to the Roche Cobas TaqMan HIV-1 (Cobas TaqMan) and the Siemens Versant HIV-1 RNA 3.0 (bDNA 3.

HBV viremia in newborns of HBsAg(+) predominantly Caucasian HBeAg(-) mothers.

Background: Hepatitis B virus infection is an important public health problem worldwide and eliminating mother-to-infant transmission is important to decrease the prevalence of chronic HBV-infection. Although, immunoprophylaxis given at birth largely prevents mother-to-infant transmission, perinatal HBV viremia has been reported in HBsAg(-) newborns born mainly to HBeAg(+) women in endemic areas.

Objectives: To examine the incidence of perinatal HBV viremia in newborns of HBsAg(+) predominantly HBeAg(-) mothers.

Development of a new ultra sensitive real-time PCR assay (ultra sensitive RTQ-PCR) for the quantification of HBV-DNA.

Background: Improved sensitivity of HBV-DNA tests is of critical importance for the management of HBV infection. Our aim was to develop and assess a new ultra sensitive in-house real-time PCR assay for HBV-DNA quantification (ultra sensitive RTQ-PCR).

Results: Previously used HBV-DNA standards were calibrated against the WHO 1st International Standard for HBV-DNA (OptiQuant(R) HBV-DNA Quantification Panel, Accrometrix Europe B.

Quantitative detection of the M204V hepatitis B virus minor variants by amplification refractory mutation system real-time PCR combined with molecular beacon technology.

Mutations in the highly conserved tyrosine-methionine-aspartate-aspartate (YMDD) motif are frequently associated with resistance to antivirals and represent a major concern in the treatment of hepatitis B virus (HBV) infection. Conventional methods fail to detect minority populations of drug-resistant viral quasispecies if they represent less than 25% of the total sample virus population. The amplification refractory mutation system real-time PCR (ARMS RT-PCR) was combined with molecular beacon technology using the LightCycler system.

Development and assessment of a multiplex real-time PCR assay for quantification of human immunodeficiency virus type 1 DNA.

Previous studies showed that high levels of human immunodeficiency virus type 1 (HIV-1) DNA are associated with a faster progression to AIDS, an increased risk of death, and a higher risk of HIV RNA rebound in patients on highly active antiretroviral therapy. Our objective was to develop and assess a highly sensitive real-time multiplex PCR assay for the quantification of HIV-1 DNA (RTMP-HIV) based on molecular beacons. HIV-1 DNA quantification was carried out by RTMP in a LightCycler 2.

Molecular characterization of occult hepatitis B cases in Greek blood donors.

The use of sensitive nucleic acid testing for hepatitis B virus in blood donors revealed a number of HBV DNA(+) cases among HBsAg(-) donors, a status known as occult HBV infection. The purpose of this study was the serological and molecular characterization of occult HBV infection in Greek blood donors. A prospective study was undertaken in order to identify occult HBV infection cases in blood donors.

Emergence of an NNRTI resistance mutation Y181C in an HIV-infected NNRTI-naive patient.

The purpose of our study was to examine the emergence of the Y181C resistance mutation in an NNRTI-naive subject (index patient) at different time points. Phylogenetic trees in protease (PR) and partial reverse transcriptase (RT) regions were inferred by the maximum likelihood (ML) method. The Y181C mutation was detected for the first time when the patient was receiving d4T + ddI + LPV/r; the previous drug combination was 3TC + AZT + IDV.

HBV virological assessment.

Management of hepatitis B virus (HBV) infected patients involves serological diagnosis, quantitation of HBV-DNA and measurement of HBV drug resistance. Different serological markers such as HBsAg, anti-HBs, anti-HBc (total and IgM), HBeAg and anti-HBe are assessed by immunoassays in order to define the infection status. The emergence of surface mutants however is a continuous challenge to design more effective immunoassays.

A viral kinetic study using pegylated interferon alfa-2b and/or lamivudine in patients with chronic hepatitis B/HBeAg negative.

We studied viral dynamic parameters in 44 chronic hepatitis B/hepatitis B e antigen (HBeAg)(-) patients treated with pegylated interferon alfa-2b (PEG-IFN) 100 or 200 microg weekly or lamivudine 100 mg daily or the combination of PEG-IFN 100 or 200 microg with lamivudine. Patients receiving PEG-IFN monotherapy exhibited viral load oscillations between weekly injections, which were resolved by the addition of lamivudine. The median pharmacological delay was estimated at 4.