Journal of Clinical Virology最新文献

Background

The advent of lateral flow devices (LFDs) for SARS-CoV-2 detection enabled widespread use of rapid self-tests during the pandemic. While self-testing using LFDs is now common, whether self-testing provides comparable performance to professional testing was a key question that remained important for pandemic planning.

Methods

Three prospective multi-centre studies were conducted to compare the performance of self- and professional testing using LFDs. Participants tested themselves or were tested by trained (professional) testers at community testing sites in the UK. Corresponding qRT-PCR test results served as reference standard. The performance of Innova, Orient Gene and SureScreen LFDs by users (self) and professional testers was assessed in terms of sensitivity, specificity, and kit failure (void) rates. Impact of age, sex and symptom status was analysed using logistic regression modelling.

Results

16,617 participants provided paired tests, of which 15,418 were included in the analysis. Self-testing with Innova, Orient Gene or SureScreen LFDs achieved sensitivities of 50 %, 53 % or 72 %, respectively, compared to qRT-PCR. Self and professional LFD testing showed no statistically different sensitivity with respect to corresponding qRT-PCR testing. Specificity was consistently equal to or higher than 99 %. Sex and age had no or only marginal impact on LFD performance while sensitivity was significantly higher for symptomatic individuals. Sensitivity of LFDs increased strongly to up to 90 % with higher levels of viral RNA measured by qRT-PCR.

Conclusions

Our results support SARS-CoV-2 self-testing with LFDs, especially for the detection of individuals whose qRT-PCR tests showed high viral concentrations.

Introduction

Quality control (QC) is one component of an overarching quality management system (QMS) that aims at assuring laboratory quality and patient safety. QC data must be acceptable prior to reporting patients’ results. Traditionally, QC statistics, records, and corrective actions were tracked at the Johns Hopkins Molecular Virology Laboratory using Microsoft Excel. Unity Real-Time (UnityRT), a QMS software (Bio-Rad Laboratories), which captures and analyzes QC data by instrument and control lot per assay, was implemented and its impact on the workflow was evaluated. The clinical utility of real-time QC monitoring using UnityRT is highlighted with a case of subtle QC trending of HIV-1 quantitative control results.

Methods

A comprehensive workflow analysis was performed, with a focus on Epstein Barr Virus (EBV) and BKV quantitative viral load testing (Roche cobas 6800). The number of QC steps and time to complete each step were assessed before and after implementing UnityRT.

Results

Our assessment of monthly QC data review revealed a total of 10 steps over 57 min when using Microsoft Excel, versus 6 steps over 11 min when using UnityRT. HIV-1 QC monitoring revealed subtle trending of the low positive control above the mean from November to December 2022, correlating with a change in the reagent kit lot. This associated with a shift in patients’ results from positives below the lower limit of quantification to positives between 20 and 100 copies/mL.

Conclusions

UnityRT consolidated QC analyses, monitoring, and tracking corrective actions. UnityRT was associated with significant time savings, which along with the interfaced feature of the QC capture and data analysis, have improved the workflow and reduced the risk of laboratory errors. The HIV-1 case revealed the value of the real-time monitoring of QC.

Background

JC polyomavirus (JCPyV) persists asymptomatic in more than half of the human population. Immunocompromising conditions may cause reactivation and acquisition of neurotropic rearrangements in the viral genome, especially in the non-coding control region (NCCR). Such rearranged JCPyV strains are strongly associated with the development of progressive multifocal leukoencephalopathy (PML).

Methods

Using next-generation sequencing (NGS) and bioinformatics tools, the NCCR was characterized in cerebrospinal fluid (CSF; N = 21) and brain tissue (N = 16) samples from PML patients (N = 25), urine specimens from systemic lupus erythematosus patients (N = 2), brain tissue samples from control individuals (N = 2) and waste-water samples (N = 5). Quantitative PCR was run in parallel for diagnostic PML samples.

Results

Archetype NCCR (i.e. ABCDEF block structure) and archetype-like NCCR harboring minor mutations were detected in two CSF samples and in one CSF sample and in one tissue sample, respectively. Among samples from PML patients, rearranged NCCRs were found in 8 out of 21 CSF samples and in 14 out of 16 brain tissue samples. Complete or partial deletion of the C and D blocks was characteristic of most rearranged JCPyV strains. From ten CSF samples and one tissue sample NCCR could not be amplified.

Conclusions

Rearranged NCCRs are predominant in brain tissue and common in CSF from PML patients. Extremely sensitive detection and identification of neurotropic viral populations in CSF or brain tissue by NGS may contribute to early and accurate diagnosis, timely intervention and improved patient care.

Background

Developing countries experience limited access to HCV laboratory tests for different reasons. Providing near to real–time HCV testing and results especially to at–risk populations including those in rural settings for timely initiation to treatment is key. Within a rural Myanmar setting, we compared HCV diagnostic detection and quantification of the GeneXpert, and Advanced Biological Laboratories UltraGene–HCV assays against the gold standard and reference method Roche real–time HCV in Myanmar.

Methods

Blood samples from 158 high–risk individuals were assessed using three different methods at baseline. Results were checked for normality and log transformed. Log differences and bias between methods were calculated and correlated. Pearson's correlation coefficient was used to determine the association of HCV viral loads across all methods. The level of agreement with the standard method (Roche real time HCV) was assessed using Bland–Altman analyses.

Results

There was a strong positive correlation coefficient between all three methods with GeneXpert and Roche having the strongest, r = 0.96, (p<0.001). Compared to Roche, ABL (mean difference, 95 % limits of agreement; -0.063 and -1.4 to 1.3 Log10IU/mL) and GeneXpert (mean difference, 95 % limits of agreement; -0.28 and -0.7 to 1.8 Log10IU/mL) showed a good level of agreement with the GeneXpert being slightly superior.

Conclusion

We demonstrate the excellent performance and no-inferiority, in terms of levels of agreements of both GeneXpert and ABL compared to the Roche platform and supporting the use of the POC assays as alternative a cost-effective methods in HCV detection and diagnosis in developing and low resource settings countries.

Background

The QuantiFERONCMV (QF-CMV) assay is an interferon-gamma release assay (IGRA) used to monitor CMV-specific cell-mediated immunity (CMV-CMI) by ELISA in transplant patients. However, a chemiluminescent immunoassay (CLIA) has been developed to quantify IFNG in the QuantiFERON-Tuberculosis (TB) to detect latent TB infection.

Objectives

The aim of this work is to compare the results of QF-CMV by ELISA with those obtained by CLIA in an automated Liaison XL analyzer using the QuantiFERON-TB Gold Plus reagents.

Study Design

The QF-CMV assay had been performed by ELISA in kidney and lung transplant patients between July 2019-April 2023 at the IMIBIC/Reina Sofía Hospital (Cordoba, Spain). The remaining QF-CMV supernatants had been preserved at -80 ºC from then. Now, the IFNG levels in the same samples were determined by CLIA.

Results

One hundred and three QF-CMV supernatants from kidney (n = 50) and lung (n = 53) transplant patients were selected. An agreement of 87.4 % (kappa coefficient 0.788) between CLIA and ELISA was observed. Thirteen (12.6 %) discrepant results were detected. Some Indeterminate results by ELISA converted to Non-reactive by CLIA (0.53–0.92 IU/mL for Mitogen-Nil values). Likewise, borderline Non-reactive results by ELISA were above the 0.2 IU/mL cut-off by CLIA and then were Reactive (0.21–0.31 for CMV-Nil values).

Conclusion

CLIA shows substantial concordance with ELISA and acceptable discrepancies. The possible higher sensitivity of CLIA returns a higher number of Reactive results, which entails potential clinical consequences. Therefore, a new threshold to confer protection against CMV infection after transplantation needs to be defined.

Background

Hepatitis Delta virus (HDV) infection is a major cause of liver-related morbidity and mortality in patients infected with HBV, with a global HDV prevalence uncertain. In France, 2 to 5 % of HBs antigen (HBsAg) carriers present anti-HDV antibodies (anti-HDV). The EASL recommends testing for anti-HDV in all HBsAg-positive patients. Since January 2022, we have systematically carried out anti-HDV serology when a positive HBsAg is discovered (new HBsAg carriers).

Objectives

We evaluated the benefit of anti-HDV reflex testing after one year of practice by comparing anti-HDV and HBsAg serology data over the last six years, among the new HBsAg carriers and all the HBsAg carriers.

Study design

HBsAg and anti-HDV were screened using the Abbott Architect HBsAg quanti kit and the DIA.PRO HDVAb kit. Serological, demographic, virological, and clinical data were analyzed.

Results

Implementing anti-HDV reflex testing leads to more than a 2-fold increase in diagnoses of HDV infection among all HBsAg carriers. If the anti-HDV positive rate remains stable among the new HBsAg carriers, a significant increase in the anti-HDV positive rate from 6.8 % to 10.3 % was observed considering all HBsAg carriers. Interestingly, the discovery of anti-HDV carriage increased from 3.9 % to 6.5 % in 2022, allowing earlier identification of HBV-HDV-infected patients and a fast referral to hepatologists for adequate clinical management and, in some cases, the introduction of bulevirtide-based therapy.

Conclusions

Our preliminary results at one year seem promising and evaluating the cost-effectiveness of reflex tests in real life with feedback would be helpful.

Background

Human papillomavirus (HPV) testing on self-samples is a valid tool for cervical cancer screening. HPV self-sample workflows need to be clinically validated to ensure safe use in screening.

Objective

This study evaluated the fully automated NeuMoDx HPV Assay self-sample workflow that is compiled of the NeuMoDx HPV assay and the NeuMoDx 96/288 Molecular Systems, for clinical performance and reproducibility on Evalyn Brush-collected self-samples.

Methods

The clinical performance of the NeuMoDx HPV Assay self-sample workflow for cervical intraepithelial neoplasia grade 2 or worse (CIN2+) and CIN3+ was evaluated on 987 self-samples obtained from women attending national organized HPV-based cervical cancer screening by a noninferiority analysis relative to reference workflows using either HPV-Risk Assay or high-risk HPV GP5+/6+-PCR. Intra- and inter-laboratory reproducibility of the NeuMoDx HPV Assay self-sample workflow using both NeuMoDx 96 and 288 Molecular Systems was assessed on 520 self-samples in three laboratories.

Results

The clinical sensitivity and specificity of the NeuMoDx HPV Assay self-sample workflow for the detection of CIN2+ and CIN3+ were found to be non-inferior to the reference workflows using either HPV-Risk Assay or high-risk HPV GP5+/6+-PCR, with all p-values <0.034. The NeuMoDx HPV Assay self-sample workflow exhibited an intra-laboratory reproducibility of 94.4 % (95 %CI:92.5–96.1 %) with kappa value 0.86 (95 %CI:0.81–0.91). Inter-laboratory agreement was high (all ≥93.4 % and all kappa values ≥0.83).

Conclusions

The NeuMoDx HPV Assay self-sample workflow demonstrated high clinical accuracy for CIN2+/3+ and high reproducibility. The NeuMoDx HPV Assay self-sample workflow can be considered suitable for cervical cancer screening purposes.

Background

Varicella zoster virus (VZV) is among the leading pathogens causing meningitis and encephalitis. While VZV-PCR-positive CSF is considered a gold-standard for diagnosis, it is not-uncommon to detect VZV-DNA in CSF of patients with other acute or chronic illness. Our goal was to determine the clinical relevance of VZV-PCR-positive CSF when investigating patients with neurological symptoms.

Methods

In this retrospective cohort from the largest hospital in Israel, we collected demographic, clinical and laboratory data of patients with VZV-PCR-positive CSF, analyzing the significance of various parameters.

Results

During a 5-years study, 125 patient-unique VZV-PCR-positive CSFs were recorded, in which only 9 alternative diagnoses were noted. The commonest symptoms were headache (N = 104, 83 %) and rash (N = 96, 76 %). PCR-cycle-threshold (Ct), a surrogate of viral burden, did not significantly vary across the clinical manifestations; however, patients with rash and Ct<35 were prone to develop stroke in the following year (N = 6, 7 %). Empiric nucleoside-analogue treatment was not associated with a better outcome compared to treatment administered upon a positive-PCR result.

Discussion

Our findings suggest that in patients with neurological symptoms, detection of VZV-DNA in CSF renders VZV the probable culprit. Nevertheless, a systematic evaluation of treatment and follow-up algorithms of patients with suspected or proved VZV meningitis and encephalitis is needed. The benefits of a prompt treatment should be weighed against the potential complications of nucleoside-analogue. Conversely, the propensity for stroke in patients with higher viral-burden, necessitates further studies assessing VZV causal role, directing additional workup, treatment and monitoring policy.

Background: Human Adenoviruses are a common cause of disease and can cause significant morbidity and mortality in immunocompromised patients. Nosocomial transmission events can occur with whole genome sequencing playing a crucial role. This study evaluates the performance of a custom designed SureSelect^XT target enrichment assay based on 14 adenovirus genomes for sequencing direct from clinical samples.

Methods: Modifications were made to the SureSelect^XT low input protocol to enhance performance for viral targets. Consensus sequences were generated using an in-house designed three stage bioinformatics pipeline. We assessed, percentage of on target reads, average depth of coverage and percentage genome coverage to determine assay performance across a range of sample matrices.

Results: Whole genome sequences were successfully generated for 91.6 % of samples assessed. Adenovirus DNA concentration was a good indicator of enrichment success. Highly specific enrichment was observed with only 6 % of samples showing < 50 % on target reads. Respiratory and faecal samples performed well where bloods showed higher levels of non-specific enrichment likely confounded by low adenovirus DNA concentrations. Protocol performance did not appear impacted by Adenovirus type or species.

Conclusion: Overall performance of this modified SureSelect^XT protocol appears in line with previously published works although there are some confounding factors requiring further investigation. The use of a small RNA bait set has the potential to reduce associated costs which can be prohibitive.

Background

Tackling HIV drug resistance is one of major challenges for ending AIDS epidemic, but the elevated expense of cutting-edge genomics hampers the advancement of HIV genotype testing for clinical care.

Methods

We developed a HIV genotype testing pipeline that centers on a cost-efficient portable Nanopore sequencer. Accuracy verification was conducted through comparison with parallel data obtained via fixed-site Pacbio sequencing. Our complete pol-gene sequencing strategy coupled with portable high-throughput sequencing was applied to identify drug resistance mutations across 58 samples sourced from the ART-treated Los Angeles General Medical Center Rand Schrader Clinic (LARSC) cohort (7 samples from 7 individuals) and the ART-naïve Center for HIV/AIDS Vaccine Immunology (CHAVI) cohort (51 samples from 38 individuals).

Results

A total of 472 HIV consensus sequences, each tagged with a unique molecular identifier, were produced from over 1.4 million bases acquired through portable Nanopore sequencing, which matched those obtained independently via Pacbio sequencing. With this desirable accuracy, we first documented the linkage of multidrug cross-resistance mutations across Integrase Strand Transfer inhibitors (INSTIs) and Non-Nucleoside Reverse Transcriptase Inhibitors (NNRTIs) from an individual failing a second-generation INSTI regimen. By producing more than 500 full-length HIV pol gene sequences in a single portable sequencing run, we detected Protease Inhibitor (PI), Nucleoside Reverse Transcriptase Inhibitor (NRTI), NNRTI and INSTI resistance mutations. All drug resistance mutations identified through portable sequencing were cross-validated using fixed-site Pacbio sequencing.

Conclusions

Our accurate and affordable HIV drug resistance testing solution is adaptable for both individual patient care and large-scale surveillance initiatives.