Virology Laboratory, Microbiology Department, University Hospital 12 de Octubre, Madrid, Spain.
Biomedical Research Institute imas12. University Hospital, 12 de Octubre, Madrid, Spain.
J Clin Virol. 2020 Aug;129:104504. doi: 10.1016/j.jcv.2020.104504. Epub 2020 Jun 10.
Retrospective diagnosis of congenital cytomegalovirus (cCMV) infection may be challenging mainly because of the high variable sensitivity of PCR on dried blood spots (DBS) samples.
To compare cytomegalovirus (CMV) viral load (VL) values in different samples obtained at birth from infants with cCMV infection. To evaluate dried umbilical cord (DUC) samples as an alternative to DBS.
Saliva and/or urine, peripheral blood (PB), and DBS from 16 infants with confirmed cCMV infection were collected at birth. CMV VL were determined by DNA extraction and real-time polymerase chain reaction (rt-PCR). In two cases, VL was determined from DUC samples.
Six (37.5 %) of the 16 infants were symptomatic, and 10 (62.5 %) were asymptomatic. The CMV VL found in saliva (median: 1,958,525 [IQR: 597,683-3,483,843] IU/mL) and in urine (median: 691,865 [IQR: 188,489.5-3,175,696] UI/mL) were both higher than those found in PB (median: 1115 [IQR: 364-4,002] IU/mL), p: 0.0001). Symptomatic infants presented 100 % of detectable VL in PB and 50 % in DBS. Asymptomatic infants showed 75 % of detectable VL in PB and 30 % in DBS. The VL in DUC were 22,341, 9754 IU/mL and 994 IU/mL.
When VL was detectable in PB, the values were lower than in saliva or urine, in both symptomatic and asymptomatic cases of cCMV. The low sensitivity in DBS samples could be due to low blood volume content, making CMV VL undetectable even when using optimised extraction and PCR protocols. In our limited experience, DUC could play a complementary diagnostic role when DBS VL is undetectable.
先天性巨细胞病毒（cCMV）感染的回顾性诊断可能具有挑战性，主要是因为干血斑（DBS）样本的 PCR 灵敏度存在高度差异。
比较先天性巨细胞病毒（CMV）感染患儿出生时不同样本中的病毒载量（VL）值。评估脐带干血（DUC）样本作为 DBS 的替代样本。
收集 16 例确诊 cCMV 感染婴儿的唾液和/或尿液、外周血（PB）和 DBS。通过 DNA 提取和实时聚合酶链反应（rt-PCR）测定 CMV VL。在两个病例中，通过 DUC 样本测定 VL。
16 例婴儿中 6 例（37.5%）有症状，10 例（62.5%）无症状。唾液（中位数：1,958,525 [IQR：597,683-3,483,843] IU/mL）和尿液（中位数：691,865 [IQR：188,489.5-3,175,696] UI/mL）中的 CMV VL 均高于 PB（中位数：1115 [IQR：364-4,002] IU/mL），p：0.0001）。有症状婴儿的 PB 和 DBS 中均有 100%的 VL 可检测到。无症状婴儿的 PB 和 DBS 中 VL 可检测率分别为 75%和 30%。DUC 的 VL 分别为 22,341、9754IU/mL 和 994IU/mL。
当 PB 中 VL 可检测到，其值低于 PB 中唾液或尿液中的值，无论是有症状还是无症状的 cCMV。DBS 样本的低灵敏度可能是由于血容量含量低，即使使用优化的提取和 PCR 方案，CMV VL 也无法检测到。根据我们有限的经验，当 DBS VL 不可检测时，DUC 可发挥补充诊断作用。
