Comparative evaluation of a triplex nucleic acid test for detection of HBV DNA, HCV RNA, and HIV-1 RNA, with the Procleix Tigris System

Lamivudine 24-month-long prophylaxis is a safe and efficient choice for the prevention of hepatitis B virus reactivation in HBsAg-negative/HBcAb-positive patients with advanced DLBCL undergoing upfront R-CHOP-21

Introduction

Occult hepatitis B infection (OBI) is a condition where replication-competent hepatitis B virus-DNA (HBV-DNA) is present in the liver, with or without HBV-DNA in the blood [<200 international units (IU)/ml or absent] in HB surface antigen (HBsAg)-negative/HB core antibody (HBcAb)-positive individuals. In patients with advanced stage diffuse large B-cell lymphoma (DLBCL) undergoing 6 cycles of R-CHOP-21+2 additional R, OBI reactivation is a frequent and severe complication. There is no consensus among recent guidelines on whether a pre-emptive approach or primary antiviral prophylaxis is the best solution in this setting of patients. In addition, questions still unresolved are the type of prophylactic drug against HBV and adequate prophylaxis duration.

Methods

In this case-cohort study, we compared a prospective series of 31 HBsAg-/HBcAb+ patients with newly diagnosed high-risk DLBCL receiving lamivudine (LAM) prophylaxis 1 week before R-CHOP-21+2R until 18 months after (24-month LAM series) versus 96 HBsAg-/HBcAb+ patients (from January 2005 to December 2011) undergoing a pre-emptive approach (pre-emptive cohort) and versus 60 HBsAg-/HBcAb+ patients, from January 2012 to December 2017, receiving LAM prophylaxis [1 week before immunochemotherapy (ICHT) start until 6 months after] (12-month LAM cohort). Efficacy analysis focused primarily on ICHT disruption and secondarily on OBI reactivation and/or acute hepatitis.

Results

In the 24-month LAM series and in the 12-month LAM cohort, there were no episodes of ICHT disruption versus 7% in the pre-emptive cohort (P = 0.05). OBI reactivation did not occur in any of the 31 patients in the 24-month LAM series versus 7 out of 60 patients (10%) in the 12-month LAM cohort or 12 out of 96 (12%) patients in the pre-emptive cohort (P = 0.04, by χ ² test). No patients in the 24-month LAM series developed acute hepatitis compared with three in the 12-month LAM cohort and six in the pre-emptive cohort.

Discussion

This is the first study collecting data regarding a consistent and homogeneous large sample of 187 HBsAg-/HBcAb+ patients undergoing standard R-CHOP-21 for aggressive lymphoma. In our study, 24-month-long prophylaxis with LAM appears to be the most effective approach with a null risk of OBI reactivation, hepatitis flare-up, and ICHT disruption.

Current laboratory tests for diagnosis of hepatitis B virus infection

BACKGROUND

Hepatitis B virus (HBV) has a long history in human infectious diseases. HBV infection can progress chronically, leading to cancer. After introduction of a vaccine, the overall incidence rate of HBV infection has decreased, although it remains a health problem in many countries.

PURPOSE

The aim of this review was to summarise current diagnostic efforts for HBV infection and future HBV diagnosis perspectives.

METHODS

We reviewed and summarised current laboratory diagnosis related with HBV infection in clinical practice.

RESULTS

There have been various serologic- and molecular-based methods to diagnose acute or chronic HBV infection. Since intrahepatic covalently closed circular DNAs (cccDNAs) function as robust HBV replication templates, cure of chronic HBV infection is limited. Recently, new biomarkers such as hepatitis B virus core-related antigen (HBcrAg) and HBV RNA have emerged that appear to reflect intrahepatic cccDNA status. These new biomarkers should be validated before clinical usage.

CONCLUSION

An effective diagnostic approach and current updated knowledge of treatment response monitoring are important for HBV infection management. Brand new ultrasensitive and accurate immunologic methods may pave the way to manage HBV infection in parallel with immunotherapy era.

Update of the statements on biology and clinical impact of occult hepatitis B virus infection

In October 2018 a large number of international experts with complementary expertise came together in Taormina to participate in a workshop on occult hepatitis B virus infection (OBI). The objectives of the workshop were to review the existing knowledge on OBI, to identify issues that require further investigation, to highlight both existing controversies and newly emerging perspectives, and ultimately to update the statements previously agreed in 2008. This paper represents the output from the workshop.

Regression analysis and variable selection for two-stage multiple-infection group testing data

Group testing, as a cost-effective strategy, has been widely used to perform large-scale screening for rare infections. Recently, the use of multiplex assays has transformed the goal of group testing from detecting a single disease to diagnosing multiple infections simultaneously. Existing research on multiple-infection group testing data either exclude individual covariate information or ignore possible retests on suspicious individuals. To incorporate both, we propose a new regression model. This new model allows us to perform a regression analysis for each infection using multiple-infection group testing data. Furthermore, we introduce an efficient variable selection method to reveal truly relevant risk factors for each disease. Our methodology also allows for the estimation of the assay sensitivity and specificity when they are unknown. We examine the finite sample performance of our method through extensive simulation studies and apply it to a chlamydia and gonorrhea screening data set to illustrate its practical usefulness.

Prevalence of Hepatitis B Virus (HBV) Among Blood Donors in Eastern Saudi Arabia: Results From a Five-Year Retrospective Study of HBV Seromarkers

Background

Transfusion-transmissible hepatitis B virus (HBV) infection is a major problem worldwide. Recently, confirmatory nucleic acid tests (NATs) for HBV DNA have been employed in several countries. We assessed the prevalence and yearly trends of HBV infection in blood donors in the Eastern Province of Saudi Arabia, screening for HBV surface antigen (HBsAg), antibody against HBV core antigen (anti-HBc), and HBV DNA.

Methods

Between 2011 and 2015, a total of 22,842 donors were screenedfor HBsAg, anti-HBc, and HBV DNA using the HBsAg Qualitative II kit (Abbott, Ireland Diagnostics Division, Sligo, Ireland), ARCHITECT Anti-hepatitis B core antigen antibody (HBc) II Assay kit (Abbott GmbH & Co. KG, Wiesbaden, Germany), and NAT Procleix Ultrio Elite Assay kit (Grifols Diagnostic Solutions Inc., Los Angeles, CA, USA), respectively.

Results

A total of 739 (3.24%) donors were HbsAg(+), anti-HBc(+), or HBV DNA(+); 63 (0.28%) were HbsAg(+), anti-HBc(+), and HBV DNA(+). Twelve (0.05%) were anti-HBc(+) and HBV DNA(+) but HBsAg(−); they were considered to have occult infection. Further, 664 (2.91%) were HBsAg(−) but anti-HBc(+), indicating chronic or resolving infection. HBV prevalence increased significantly from 2011 to 2012, increased marginally till 2013, and showed a decreasing trend from 2013 (P>0.05).

Conclusions

The five-year prevalence of HBV infection among blood donors in the Eastern Province of Saudi Arabia (3.24%) is lower than that reported for other regions in the country. The occult HBV infection rate of 0.05% emphasizes the importance of NATs in isolating potential infectious blood units.

Dynamic changes in biomarkers in acute human immunodeficiency virus infections: a case report

Background

The highest incidence of human immunodeficiency virus infection in China is among men who have sex with men. This case report aims to describe the dynamic changes in biomarkers in an acute human immunodeficiency virus infection of a Han Chinese man who has sex with men, and to illustrate the possibility of using these biomarkers for the early detection of human immunodeficiency virus infection in Chinese hospital settings.

Case presentation

The 25-year-old Han Chinese male patient presented himself with an 8-day history of symptoms and signs of upper respiratory viral infections to a sexually transmitted infection clinic of a hospital setting in Shanghai. The viral load of human immunodeficiency virus, p24 antigen–antibody complex, and lymphocyte subsets of blood samples were repeatedly measured over the next 39 days. The human immunodeficiency virus from serum was genotyped. This patient was diagnosed as a human immunodeficiency virus infection, and the viral genotype was CRF 01_AE. The onset of the symptoms and signs was 12 days after his last reported unprotected intercourse with a human immunodeficiency virus -infected man. The patient had detectable levels of p24 antigen at his first visit, 20 days after infection, and the HIV viral load was at the highest point (8 × 10⁶ copies/ml). A low concentration of antibody to HIV was observed in the patient’s serum 10 days after his 1st visit (30 days after infection). The confirmation of human immunodeficiency virus infection by Western blot assays was made at day 20 after his 1st visit (40 days after infection).

Conclusions

Symptoms of acute human immunodeficiency virus infection are non-specific. Specific laboratory markers appear shortly after HIV infections. The first biomarker detected from serum is the viral RNA and p24 antigen, followed by HIV-specific antibody. The results suggest that there are urgent needs for both human immunodeficiency virus antigen and antibody testing in routine medical practice, and that human immunodeficiency virus RNA testing should be recommended to detect early infection. Ethics approval was obtained from the Ethics Board of the Shanghai Dermatology Hospital.

Hierarchical group testing for multiple infections

Group testing, where individuals are tested initially in pools, is widely used to screen a large number of individuals for rare diseases. Triggered by the recent development of assays that detect multiple infections at once, screening programs now involve testing individuals in pools for multiple infections simultaneously. Tebbs, McMahan, and Bilder (2013, Biometrics) recently evaluated the performance of a two-stage hierarchical algorithm used to screen for chlamydia and gonorrhea as part of the Infertility Prevention Project in the United States. In this article, we generalize this work to accommodate a larger number of stages. To derive the operating characteristics of higher-stage hierarchical algorithms with more than one infection, we view the pool decoding process as a time-inhomogeneous, finite-state Markov chain. Taking this conceptualization enables us to derive closed-form expressions for the expected number of tests and classification accuracy rates in terms of transition probability matrices. When applied to chlamydia and gonorrhea testing data from four states (Region X of the United States Department of Health and Human Services), higher-stage hierarchical algorithms provide, on average, an estimated 11% reduction in the number of tests when compared to two-stage algorithms. For applications with rarer infections, we show theoretically that this percentage reduction can be much larger.

Mini review: current molecular methods for the detection and quantification of hepatitis B virus, hepatitis C virus, and human immunodeficiency virus type 1

The detection of acute human immunodeficiency virus (HIV), hepatitis B virus (HBV), and hepatitis C virus (HCV) infection is vital for controlling the spread of HIV, HBV, and HCV to uninfected individuals. Considering that these viruses have high replication rates and are undetectable by serological markers, early detection upon transmission is crucial. Various nucleic acid assays have been developed for diagnostics and therapeutic monitoring of infections. In the past decade, rapid and sensitive molecular techniques such as PCR have revolutionized the detection of a variety of infectious viruses, including HIV, HCV, and HBV. Here, we describe two of the most commonly used licensed methods for the detection and quantification of HIV, HCV, and HBV: the cobas TaqScreen MPX (PCR) test and the Tigris System. We used transcription-mediated amplification to review and compare the development and efficiency of these technologies.

Detection and identification of occult HBV in blood donors in Taiwan using a commercial, multiplex, multi-dye nucleic acid amplification technology screening test

BACKGROUND

The ability of a new generation commercial, multiplex, multi-dye test from Roche, the cobas TaqScreen MPX test, version 2.0, to detect and identify occult HBV infections was evaluated using routine donor samples from Kaohsiung Blood Bank, Taiwan.

STUDY DESIGN AND METHODS

A total of 5973 samples were tested by nucleic acid amplification technology (NAT); 5898 in pools of six, 66 in pools of less than six and nine samples individually. NAT-reactive samples were retested with alternative NAT tests, and follow-up samples from the donors were tested individually by NAT and for all the HBV serological markers.

RESULTS

Eight NAT-only-reactive donors were identified, and follow-up samples were obtained from six of the donors. The results indicated that all eight donors had an occult HBV infection with viral loads <12 IU/ml.

CONCLUSION

The cobas(®) TaqScreen MPX test, version 2.0, has an advantage over the current Roche blood screening test, the cobas TaqScreen MPX test, for screening donations in countries with a high prevalence of occult HBV infections since the uncertainty associated with identifying samples with very low viremia is removed by the ability of the test to identify the viral target in samples that are reactive with the cobas TaqScreen MPX test, version 2.0.

Blood screening for human immunodeficiency virus: a new algorithm to reduce the false-positive results

OBJECTIVES

The objectives to this study were to evaluate the performance of an anti-human immunodeficiency virus (HIV) blood screening test and propose a new screening algorithm for blood banks routinely using nucleic acid amplification testing (NAT) to reduce false-positive results.

BACKGROUND

Most anti-HIV enzyme-linked immunosorbent assay (ELISA) results are false-positive because of the low prevalence of HIV infection and high sensitivity of the ELISAs.

METHODS/MATERIALS

A total of 281 588 voluntary donations were collected and sera reactive on one or both anti-HIV ELISAs were confirmed by Western blot (WB) testing. All samples with nonreactive results for the two ELISAs underwent NAT. A confirmed HIV-1-positive result was defined by a reactive result on NAT or WB testing. Correlations between signal-to-cutoff ratios and the confirmed HIV-1 infection rate were analysed for each enzyme immunoassay and two-enzyme immunoassay combination. The positive predictive values (PPVs) of the current and proposed algorithms were calculated.

RESULTS

Seventy-nine donations (13·9%) were positive on WB analysis and one donation negative for anti-HIV antibody was reactive on NAT and confirmed to be a window period donation on additional follow-up testing. The PPV of the 567 donations reactive on one or two ELISAs was 13·9%. However, using the new screening algorithm, 457 donations underwent NAT immediately instead of WB testing. Only 110 donations were tested with WB and the PPV was 71·8%.

CONCLUSION

Screening for HIV is sensitive, specific and time saving for donors with this algorithm, which is suitable for HIV screening in low prevalence settings.