Dataset Information

Cellular DNA quantification in respiratory samples for the normalization of viral load: a real need?

ABSTRACT:

Background

Respiratory tract infections have an enormous social economic impact, with high incidence of hospitalization and high costs. Adequate specimen collection is the first crucial step for the correct diagnosis of viral respiratory infections.

Objectives

The present retrospective study aimed: i) to verify the cell yield obtained from sampling the nasal respiratory tract using mid-turbinate flocked swabs; ii) to evaluate the normalization of viral load, based on cell number; and iii) to compare the kinetics of viral infection obtained with normalized vs non-normalized viral load.

Study design

The number of cells were quantified by real-time PCR in residual extract of nasal swabs tested for respiratory viruses detection and stored at -80?°C in a universal transport medium (UTM™).

Results

A total of 513 virus-positive and 226 virus-negative samples were analyzed. Overall, a median of 4.42 log₁₀ ?2-microgolubin DNA copy number/ml of UTM^™ (range 1.17-7.26) was detected. A significantly higher number of cells was observed in virus-positive as compared to virus-negative samples (4.75 vs 3.76; p?10 RNA copies/ml of UTM^™ and log₁₀ RNA copies/median number of cells were compared in virus-positive samples and a strict correlation (r?=?0.89, p?10 (range -1.99 to 0.40).

Conclusions

The normalization of viral load using cellular load compliments the validation of real-time PCR results in the diagnosis of respiratory viruses but is not strictly needed.

SUBMITTER: Piralla A

PROVIDER: S-EPMC7173160 | biostudies-literature | 2018 Oct

REPOSITORIES: biostudies-literature

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Publications

Cellular DNA quantification in respiratory samples for the normalization of viral load: a real need?

Piralla Antonio A Giardina Federica F Rovida Francesca F Campanini Giulia G Baldanti Fausto F

Journal of clinical virology : the official publication of the Pan American Society for Clinical Virology 20180727

<h4>Background</h4>Respiratory tract infections have an enormous social economic impact, with high incidence of hospitalization and high costs. Adequate specimen collection is the first crucial step for the correct diagnosis of viral respiratory infections.<h4>Objectives</h4>The present retrospective study aimed: i) to verify the cell yield obtained from sampling the nasal respiratory tract using mid-turbinate flocked swabs; ii) to evaluate the normalization of viral load, based on cell number; ...[more]

PMID: 30103163

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Project description:Viral load (VL) monitoring is the standard of care in developing country settings for detecting HIV treatment failure. Since 2010 the World Health Organization has recommended a phase-in approach to VL monitoring in resource-limited settings. We conducted a systematic review of the accuracy and precision of HIV VL technologies for treatment monitoring.A search of Medline and Embase was conducted for studies evaluating the accuracy or reproducibility of commercially available HIV VL assays. 37 studies were included for review including evaluations of the Amplicor Monitor HIV-1 v1.5 (n?=?25), Cobas TaqMan v2.0 (n?=?11), Abbott RealTime HIV-1 (n?=?23), Versant HIV-1 RNA bDNA 3.0 (n?=?15), Versant HIV-1 RNA kPCR 1.0 (n?=?2), ExaVir Load v3 (n?=?2), and NucliSens EasyQ v2.0 (n?=?1). All currently available HIV VL assays are of sufficient sensitivity to detect plasma virus levels at a lower detection limit of 1,000 copies/mL. Bias data comparing the Abbott RealTime HIV-1, TaqMan v2.0 to the Amplicor Monitor v1.5 showed a tendency of the Abbott RealTime HIV-1 to under-estimate results while the TaqMan v2.0 overestimated VL counts. Compared to the Amplicor Monitor v1.5, 2-26% and 9-70% of results from the Versant bDNA 3.0 and Abbott RealTime HIV-1 differed by greater than 0.5log10. The average intra and inter-assay variation of the Abbott RealTime HIV-1 were 2.95% (range 2.0-5.1%) and 5.44% (range 1.17-30.00%) across the range of VL counts (2log10-7log10).This review found that all currently available HIV VL assays are of sufficient sensitivity to detect plasma VL of 1,000 copies/mL as a threshold to initiate investigations of treatment adherence or possible treatment failure. Sources of variability between VL assays include differences in technology platform, plasma input volume, and ability to detect HIV-1 subtypes. Monitoring of individual patients should be performed on the same technology platform to ensure appropriate interpretation of changes in VL. Prospero registration # CD42013003603.

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Dataset Information

Cellular DNA quantification in respiratory samples for the normalization of viral load: a real need?

Background

Objectives

Study design

Results

Conclusions

Publications

Cellular DNA quantification in respiratory samples for the normalization of viral load: a real need?

Similar Datasets

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