Department of Neonatology, Hadassah Hebrew University Medical Center, Jerusalem, Israel.
Clinical Virology Unit, Department of Clinical Microbiology and Infectious Diseases, Hadassah Hebrew University Medical Center, Jerusalem, Israel.
J Infect Dis. 2019 Oct 22;220(11):1790-1796. doi: 10.1093/infdis/jiz373.
Saliva real-time polymerase chain reaction (PCR) was shown to be sensitive and specific for the detection of congenital cytomegalovirus (cCMV) in universal screening studies. In the current study, we assessed the performance of saliva real-time PCR in newborns undergoing targeted cCMV screening.
Saliva real-time PCR results were prospectively correlated with reference-standard urine detection in newborns undergoing targeted cCMV screening over a 3-year period, in successive validation (concurrent testing of all saliva and urine specimens) and routine-screening (confirmatory urine testing of positive saliva results) implementation phases.
The sensitivity, specificity, and positive and negative predictive values of saliva real-time PCR were 98.3% (95% confidence interval, 90.8%-99.9%), 91.5% (89.3%-93.3%), 45.6% (36.7%-54.7%), and 99.9% (99.2%-99.9%), respectively, in 856 concurrently tested newborns. True-positive saliva real-time PCR detection (defined in relation to urine detection) was associated with earlier saliva sampling (P = .002) and a higher saliva viral load (P < .001). We further identified a saliva viral load cutoff value that reliably distinguished between true-positive and false-positive saliva results.
In newborns undergoing targeted screening for cCMV, saliva real-time PCR is highly sensitive yet has a low positive predictive value, necessitating confirmatory testing. Early sampling and application of a validated viral load cutoff could improve the assay performance and support its large-scale implementation in this growing clinical setting.
唾液实时聚合酶链反应（PCR）已被证明在通用筛查研究中对先天性巨细胞病毒（cCMV）的检测具有敏感性和特异性。在本研究中，我们评估了唾液实时 PCR 在接受靶向 cCMV 筛查的新生儿中的表现。
在 3 年期间，在连续的验证（同时检测所有唾液和尿液标本）和常规筛查（阳性唾液结果的确认性尿液检测）实施阶段，前瞻性地将唾液实时 PCR 结果与参考标准尿液检测相关联。
在 856 例同时检测的新生儿中，唾液实时 PCR 的敏感性、特异性、阳性和阴性预测值分别为 98.3%（95%置信区间，90.8%-99.9%）、91.5%（89.3%-93.3%）、45.6%（36.7%-54.7%）和 99.9%（99.2%-99.9%）。真正的阳性唾液实时 PCR 检测（与尿液检测相关定义）与早期唾液取样（P =.002）和较高的唾液病毒载量（P <.001）相关。我们进一步确定了一个唾液病毒载量截断值，可以可靠地区分真正阳性和假阳性的唾液结果。
在接受靶向 cCMV 筛查的新生儿中，唾液实时 PCR 具有高度敏感性，但阳性预测值较低，需要进行确认性检测。早期取样和应用经过验证的病毒载量截断值可以提高检测性能，并支持在这个不断增长的临床环境中大规模实施。
