Abbate Isabella, Piralla Antonio, Calvario Agata, Callegaro Annapaola, Giraldi Cristina, Lunghi Giovanna, Gennari William, Sodano Giuseppe, Ravanini Paolo, Conaldi Pier Giulio, Vatteroni Marialinda, Gaeta Aurelia, Paba Pierpaolo, Cavallo Rossana, Baldanti Fausto, Lazzarotto Tiziana
Laboratorio di Virologia, INMI L. Spallanzani, Roma, Italy.
SS Virologia Molecolare, SC Microbiologia e Virologia, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy.
J Clin Virol. 2016 Sep;82:76-83. doi: 10.1016/j.jcv.2016.07.001. Epub 2016 Jul 2.
Inter-laboratory variability in quantifying pathogens involved in viral disease following transplantation may have a great impact on patient care, especially when pre-emptive strategies are used for prevention.
The aim of this study was to analyze the variability in quantifying CMV, EBV and BKV DNA from 15 virology laboratories of the Italian Infections in Transplant Working Group (GLaIT) involved in monitoring transplanted patients.
Panels from international Quality Control programs for Molecular Diagnostics (QCMD, year 2012), specific for the detection of CMV in plasma, CMV in whole blood (WB), EBV and BKV were used. Intra- and inter-laboratory variability, as well as, deviations from QCMD consensus values were measured.
100% specificity was obtained with all panels. A sensitivity of 100% was achieved for EBV and BKV evaluations. Three CMV samples, with concentrations below 3 log10 copies/ml, were not detected by a few centers. Mean intra-laboratory variability (% CV) was 1.6 for CMV plasma and 3.0 for CMV WB. Mean inter-laboratory variability (% CV) was below 15% for all of the tested panels. Inter-laboratory variability was higher for CMV in WB with respect to the CMV plasma panel (3.0 vs 1.6% CV). The percentiles 87.7%, 58.6%, 89.6% and 74.7% fell within±0.5 log10 difference of the consensus values for CMV plasma, CMV WB, EBV and BKV panels, respectively.
An acceptable intra- and inter-laboratory variability, in comparison with international standards was observed in this study. However, further harmonization in viral genome quantification is a reasonable goal for the future.
移植后病毒性疾病中病原体定量的实验室间差异可能对患者护理产生重大影响，尤其是在采用抢先预防策略时。
本研究旨在分析意大利移植感染工作组（GLaIT）的15个病毒学实验室在监测移植患者时，对巨细胞病毒（CMV）、 Epstein-Barr病毒（EBV）和BK病毒（BKV）DNA定量的差异。
使用国际分子诊断质量控制计划（QCMD，2012年）的样本，这些样本专门用于检测血浆中的CMV、全血（WB）中的CMV、EBV和BKV。测量了实验室内和实验室间的差异，以及与QCMD共识值的偏差。
所有样本的特异性均为100%。EBV和BKV评估的灵敏度达到100%。少数中心未检测到三个浓度低于3 log10拷贝/ml的CMV样本。CMV血浆的平均实验室内差异（%CV）为1.6，CMV全血为3.0。所有测试样本的平均实验室间差异（%CV）均低于15%。与CMV血浆样本相比，CMV全血的实验室间差异更高（3.0%CV对1.6%CV）。CMV血浆、CMV全血、EBV和BKV样本的第87.7%、58.6%、89.6%和74.7%分别落在共识值±0.5 log10差异范围内。
本研究观察到与国际标准相比，实验室内和实验室间差异可接受。然而，未来进一步统一病毒基因组定量是一个合理的目标。
