Saliva Real-Time Polymerase Chain Reaction for Targeted Screening of Congenital Cytomegalovirus Infection

Maternal and congenital human cytomegalovirus infection: laboratory testing for detection and diagnosis

Human cytomegalovirus (CMV) is the leading cause of congenital infection worldwide and the most common cause of non-genetic sensorineural hearing loss. As there is no vaccine or other specific intervention to prevent congenital CMV infection, there is a need to identify maternal and congenital infections with sensitive and specific testing as early as possible. There is no widely accepted practice for screening during pregnancy or in all newborns for identification of possible cases of congenital CMV. Currently, screening during pregnancy is limited to those identified as at risk followed by fetal and/or neonatal testing when congenital infection is suspected. This review focuses primarily on the current status of laboratory testing for diagnosis of maternal and congenital CMV infections. Primary maternal infection is best diagnosed using serologic testing, including CMV IgM, IgG, and avidity testing, while fetal infection should be assessed by nucleic acid amplification testing (NAAT) of amniotic fluid. Urine and saliva NAATs are the mainstay for diagnosis of congenital CMV in the first 3 weeks of life. Testing of dried blood spots can be useful for diagnosis of congenital CMV outside of the newborn period. The gaps in knowledge such as the prognostic value of viral loads in various sample types are addressed.

Implementation of pooled saliva tests for universal screening of cCMV infection

Congenital cytomegalovirus (cCMV) is the most common intrauterine infection, leading to neurodevelopmental disabilities. Universal newborn infant screening of cCMV has been increasingly advocated. In the absence of a high-throughput screening test, which can identify all infected newborn infants, the development of an accurate and efficient testing strategy has remained an ongoing challenge. Here we assessed the implementation of pooled saliva polymerase chain reaction (PCR) tests for universal screening of cCMV, in two hospitals of Jerusalem from April 2022 through April 2023. During the 13-month study period, 15,805 infants (93.6% of all live newborn infants) were screened for cCMV using the pooled approach that has since become our routine screening method. The empirical efficiency of the pooling was six (number of tested newborn infants per test), thereby sparing 83% of the saliva tests. Only a minor 3.05 PCR cycle loss of sensitivity was observed for the pooled testing, in accordance with the theoretical prediction for an eight-sample pool. cCMV was identified in 54 newborn infants, with a birth prevalence of 3.4 per 1,000; 55.6% of infants identified with cCMV were asymptomatic at birth and would not have been otherwise targeted for screening. The study demonstrates the wide feasibility and benefits of pooled saliva testing as an efficient, cost-sparing and sensitive approach for universal screening of cCMV.

Extensive comparison of salivary collection, transportation, preparation, and storage methods: a systematic review

BACKGROUND

Human saliva as a bodily fluid-similar to blood-is utilized for diagnostic purposes. Unlike blood sampling, collecting saliva is non-invasive, inexpensive, and readily accessible. There are no previously published systematic reviews regarding different collection, transportation, preparation, and storage methods for human saliva.

DESIGN

This study has been prepared and organized according to the preferred reporting items for systematic reviews and meta-analyses (PRISMA) 2020 guidelines. This systematic review has been registered at PROSPERO (Registration ID: CRD42023415384). The study question according to the PICO format was as followed: Comparison of the performance (C) of different saliva sampling, handling, transportation, and storage techniques and methods (I) assessed for analyzing stimulated or unstimulated human saliva (P and O). An electronic search was executed in Scopus, Google Scholar, and PubMed.

RESULTS

Twenty-three descriptive human clinical studies published between 1995 and 2022 were included. Eight categories of salivary features and biomarkers were investigated (i.e., salivary flow rate, total saliva quantity, total protein, cortisol, testosterone, DNA quality and quantity, pH and buffering pH). Twenty-two saliva sampling methods/devices were utilized. Passive drooling, Salivette®, and spitting were the most utilized methods. Sampling times with optimum capabilities for cortisol, iodine, and oral cancer metabolites are suggested to be 7:30 AM to 9:00 AM, 10:30 AM to 11:00 AM, and 14:00 PM to 20:00 PM, respectively. There were 6 storage methods. Centrifuging samples and storing them at -70 °C to -80 °C was the most utilized storage method. For DNA quantity and quality, analyzing samples immediately after collection without centrifuging or storage, outperformed centrifuging samples and storing them at -70 °C to -80 °C. Non-coated Salivette® was the most successful method/device for analyzing salivary flow rate.

CONCLUSION

It is highly suggested that scientists take aid from the reported categorized outcomes, and design their study questions based on the current voids for each method/device.

Correlation of serum biochemical parameters and saliva pH in healthy individuals

Saliva has the potential to work alongside needles in standard medical diagnosis. Yet the number of studies aimed at deciphering the biochemical communication between saliva and the rest of the body's systems is still very limited. The aim of this study is to investigate the interfluid interaction between saliva and serum by determining the correlation between saliva pH and serum biochemical parameters under mild conditions. Ultimately, using saliva may provide a stress-free diagnostic tool, but more ambitiously, the pH of saliva could present a genuine cost-effective screening tool that may immensely benefit areas with limited access to health care and diagnostic labs. Saliva and blood samples were collected from 43 randomly selected children (7-12 years), living in Jeddah, free from obesity and chronic or systemic body and mouth diseases. A complete serum biochemical analysis was performed, and the salivary pH of all samples was measured immediately at the time of collection. The correlations between saliva pH and serum biochemical parameters were investigated using Univariate and multiple linear regression models. Our results showed that pH has a weak significant positive correlation with total protein and a negative weak significant correlation with urea. Weak correlations suggest the existence of more serum factors to be investigated for their effect on the pH using a stepwise multiple linear regression. The multiple linear models' calculated saliva pH values were close to the measured values, demonstrating its possible capacity to predict saliva pH using serum parameters. The regression model's successful prediction of saliva pH using serum biochemicals reflects the significant correlations between the body fluids' parameters and invites more research to elucidate these relationships.

Multicenter Evaluation of the DiaSorin Molecular Simplexa Congenital CMV Direct PCR Test on Neonatal Saliva and Urine Specimens

Cytomegalovirus (CMV) is the most common virus associated with congenital infection worldwide and is a major cause of sensorineural hearing loss (SNHL) and developmental delay. Up to 90% of infants with congenital CMV (cCMV) infection are asymptomatic at birth, making the diagnosis challenging. Postnatal diagnosis involves testing newborn saliva and/or urine collected before 21 days of life to confirm cCMV infection. This multicenter study evaluated the performance of the Simplexa Congenital CMV Direct real-time PCR assay for the qualitative detection of CMV in newborn saliva (n = 2,023) and urine (n = 1,797) specimens. Compared to two PCR/bidirectional sequencing assays, the Simplexa Congenital CMV Direct assay demonstrated positive percent agreement (PPA) and negative percent agreement (NPA) of 98.6% and 99.9%, respectively, for saliva samples and a PPA of 97.8% and an NPA of 99.9% for urine specimens. Overall concordance was κ = 0.98 or near perfect compared to the composite reference methods with both sample types. By 95% probit analysis, the limit of detection (LoD) using the AD-169 reference strain was 350 ± 12 copies/mL in urine. The LoDs of saliva swabs in either 1 mL or 3 mL of transport medium were 274 ± 12 copies/mL and 300 ± 14 copies/mL, respectively. The Simplexa Congenital CMV Direct assay can be applied to both saliva and urine specimens collected from newborns less than 21 days of age to rapidly and reliably identify CMV infection.

Diagnostic test accuracy of PCR by saliva specimen for cytomegalovirus infection in newborn: A protocol for systematic review and meta-analysis

BACKGROUND

This study aimed to assess the diagnostic accuracy of polymerase-chain-reaction by saliva.

METHOD

We searched Pubmed, EMBASE, Cochrane Library and Web of Science. A case-control or cohort study designed to explore the saliva specimens for diagnosing the cytomegalovirus infection was eligible for this study. Sensitivity (SEN), specificity (SPE), diagnostic odds ratio (DOR), and summary receiver operating characteristic curves were calculated.

RESULTS

Nine articles were selected for the meta-analysis. For assessing saliva PCR with urine culture, the SEN, SPE, and DOR were 0.97 [95% confidential interval (CI):0.61,1.00] 1.00 [95%CI:0.99, 1.00] 15672 [95%CI:558, 440325], respectively; for assessing saliva PCR with urine PCR, the SEN, SPE, and DOR were 0.87 [95%CI:0.79, 0.92] 1.00 [95%CI:1.00, 1.00] 15637 [95%CI:5946, 41126], respectively; for total assessment, the SEN, SPE, and DOR were0.91 [95%CI:0.70, 0.98] 1.00 [95%CI:1.00, 1.00] 8493 [95%CI:1429, 50487], respectively.

CONCLUSION

We reported that saliva PCR performed well in the diagnosis of cytomegalovirus infection.

Prevalence, Outcome, and Prevention of Congenital Cytomegalovirus Infection in Neonates Born to Women With Preconception Immunity (CHILd Study)

BACKGROUND

Human cytomegalovirus (HCMV) is the leading infectious cause of congenital disabilities. We designed a prospective study to investigate the rate, outcome, and risk factors of congenital CMV (cCMV) infection in neonates born to immune women, and the potential need and effectiveness of hygiene recommendations in this population.

METHODS

The study was composed of 2 sequential parts: an epidemiology (part 1) and a prevention (part 2) study. Performance of part 2 depended upon a cCMV rate >0.4%. Women enrolled in part 1 did not receive hygiene recommendations. Newborns were screened by HCMV DNA testing in saliva and cCMV was confirmed by urine testing.

RESULTS

Saliva swabs were positive for HCMV DNA in 45/9661 newborns and cCMV was confirmed in 18 cases. The rate of cCMV was .19% (95% confidence interval [CI]: .11-.29%), and 3 out of 18 infants with cCMV had symptoms of CMV at birth. Age, nationality, occupation, and contact with children were similar between mothers of infected and noninfected newborns. Twin pregnancy (odds ratio [OR]: 7.2; 95% CI: 1.7-32.2; P = .037) and maternal medical conditions (OR: 3.9; 95% CI: 1.5-10.1; P = .003) appeared associated with cCMV. Given the rate of cCMV was lower than expected, the prevention part of the study was cancelled.

CONCLUSIONS

Newborns from women with preconception immunity have a low rate of cCMV, which appears to be mostly due to reactivation of the latent virus. Therefore, serological screening in childbearing age would be pivotal to identify HCMV-seropositive women, whose newborns have a low risk of cCMV.

CLINICAL TRIALS REGISTRATION

www.clinicaltrials.gov (NCT03973359).

An Ethical Analysis of Newborn Congenital Cytomegalovirus Screening

Congenital cytomegalovirus (cCMV) affects approximately 1 in every 200 US infants and can be associated with long-term neurodevelopmental sequelae, including sensorineural hearing loss, cerebral palsy, and intellectual disability. As cCMV is infrequently diagnosed based on clinical suspicion alone, newborn cCMV screening programs have been gaining traction, especially hearing-targeted programs which only test infants who fail their newborn hearing screen. cCMV screening programs raise unique ethical dilemmas of both under- and over-diagnosis of cCMV. In this Ethics Rounds, we present a case in which the parents of a child with symptomatic cCMV that was not recognized until 4 years of age urge the birth hospital to implement a cCMV screening program. We then ask a parent-clinician, a medical ethicist and pediatrician, and a primary care pediatrician to comment on how they would advise the hospital administration and consider the ethical and clinical implications of a cCMV screening program. The commentaries herein arrive at differing conclusions about cCMV screening. The first highlights the developmental advantages of early cCMV detection, supporting a broad approach to treatment beyond antiviral medication alone. The second explores cCMV screening from the perspective of newborn screening as a public health program, noting shortcomings in available testing platforms, and raising concerns about overdiagnosis and overtreatment. The final commentary challenges the risks of undue parental anxiety and vulnerable child syndrome as a barrier to screening, instead considering cCMV screening as a controlled opportunity to understand and support the experiences of affected children and their families.

Amniotic fluid biomarkers predict the severity of congenital cytomegalovirus infection

BACKGROUNDCytomegalovirus (CMV) is the most common intrauterine infection, leading to infant brain damage. Prognostic assessment of CMV-infected fetuses has remained an ongoing challenge in prenatal care, in the absence of established prenatal biomarkers of congenital CMV (cCMV) infection severity. We aimed to identify prognostic biomarkers of cCMV-related fetal brain injury.METHODSWe performed global proteome analysis of mid-gestation amniotic fluid samples, comparing amniotic fluid of fetuses with severe cCMV with that of asymptomatic CMV-infected fetuses. The levels of selected differentially excreted proteins were further determined by specific immunoassays.RESULTSUsing unbiased proteome analysis in a discovery cohort, we identified amniotic fluid proteins related to inflammation and neurological disease pathways, which demonstrated distinct abundance in fetuses with severe cCMV. Amniotic fluid levels of 2 of these proteins - the immunomodulatory proteins retinoic acid receptor responder 2 (chemerin) and galectin-3-binding protein (Gal-3BP) - were highly predictive of the severity of cCMV in an independent validation cohort, differentiating between fetuses with severe (n = 17) and asymptomatic (n = 26) cCMV, with 100%-93.8% positive predictive value, and 92.9%-92.6% negative predictive value (for chemerin and Gal-3BP, respectively). CONCLUSIONAnalysis of chemerin and Gal-3BP levels in mid-gestation amniotic fluids could be used in the clinical setting to profoundly improve the prognostic assessment of CMV-infected fetuses.FUNDINGIsrael Science Foundation (530/18 and IPMP 3432/19); Research Fund - Hadassah Medical Organization.

Detection of Cytomegalovirus in Urine Dried on Filter Paper

Urine is the best specimen for the diagnosis of congenital cytomegalovirus, but collection and processing of liquid urine are impractical for screening. Urine dried on filter paper was processed by the same convenient, low-cost method used by newborn screening to test blood spots and showed high sensitivity and specificity.

Universal newborn screening for congenital cytomegalovirus infection: feasibility and relevance in a French type-III maternity cohort

OBJECTIVE

Evaluation of relevance and feasibility of universal newborn congenital cytomegalovirus infection (cCMVI) screening in saliva.

DESIGN

Retrospective, population-based cohort study.

SETTING

Clamart, France, 2016-2020.

POPULATION

All neonates born consecutively in our level III maternity unit.

METHODS

CMV PCR in saliva for all neonates at birth, and, if positive, CMV PCR in urine to confirm or exclude cCMVI. Prospective and retrospective characterisation of maternal infections. ROC curve analysis to assess saliva PCR performances. Acceptability of screening among staff members evaluated by a survey.

MAIN OUTCOME MEASURES

Number of cCMVI neonates; number of expected and unexpected cCMVI.

RESULTS

Among 15 341 tested neonates, 63 had cCMVI (birth prevalence of 0.4%, 95% CI 0.3-0.5). In 50% of cases, maternal infection was a non-primary infection (NPI) during pregnancy. cCMVI was expected or suspected (maternal primary infection [PI], antenatal or neonatal signs) in 24/63 neonates (38%), and unexpected in 39/63 neonates (62%). The best CMV saliva threshold to predict cCMVI was 356 (2.55 log) copies/ml [95% CI 2.52 log-3.18 log], with an area under the ROC curve of 0.97. Over 90% of the 72 surveyed staff members reported that the screening was easy and quick. No parent refused the screening.

CONCLUSIONS

Universal screening for cCMVI with CMV PCR on saliva samples is feasible and highly acceptable to parents and healthcare providers. Over half (62%) of the cases had no prenatal/neonatal signs of cCMVI or a maternal history of CMV infection during pregnancy and would probably not have been diagnosed without universal screening.

TWEETABLE ABSTRACT

In 62% of congenital cytomegalovirus infection cases, only universal neonatal screening in saliva can detect infection.

A New Specimen for Syphilis Diagnosis: Evidence by High Loads of Treponema pallidum DNA in Saliva

BACKGROUND

DNA from many pathogens can be detected in saliva. However, the presence and quantity of Treponema pallidum DNA in patients with syphilis in saliva is unknown.

METHODS

234 patients with syphilis with different stages and 30 volunteers were enrolled. Paired saliva and plasma samples were collected from all participants. Consecutive saliva samples from 9 patients were collected every 4 hours following treatment. Treponema pallidum DNA in samples was determined by nested polymerase chain reaction (PCR) and droplet digital PCR targeting polA and Tpp47.

RESULTS

Treponema pallidum DNA detection rates in saliva and plasma were 31.0% (9/29) and 51.7% (15/29) in primary syphilis (P = .11), 87.5% (63/72) and 61.1% (44/72) in secondary syphilis (P < .001), 25.6% (21/82) and 8.5% (7/82) in latent syphilis (P = .004), and 21.6% (11/51) and 5.9% (3/51) in symptomatic neurosyphilis (P = .021), respectively. Median (range) loads of Tpp47 and polA in saliva were 627 (0-101 200) and 726 (0-117 260) copies/mL, respectively, for patients with syphilis. In plasma, however, loads of Tpp47 and polA were low: medians (range) of 0 (0-149.6) and 0 (0-176) copies/mL, respectively. Loads of T. pallidum DNA in saliva during treatment fluctuated downward; the clearance time was positively correlated with the loads of T. pallidum DNA before treatment.

CONCLUSIONS

Collection of saliva is noninvasive and convenient. The high loads of T. pallidum DNA in saliva and reduction after treatment indicated that saliva can be not only a diagnostic fluid for syphilis but also an indicator of therapeutic effectiveness.

Comparison of detection strategies for screening and confirming congenital cytomegalovirus infection in newborns in a highly seroprevalent population: a mother-child cohort study

Background

Universal screening of congenital cytomegalovirus (cCMV) infection is important for monitoring and intervention during critical stages of speech and language development. This study aimed to explore the optimal detection strategy for cCMV infection screening.

Methods

Serum samples from pregnant women and saliva and urine samples from their newborns were collected for the anti-CMV IgG and CMV DNA PCR tests, respectively. The sensitivity, specificity, and predictive values as well as the likelihood ratios of 12 potential screening strategies for cCMV infection, based on tests for saliva, urine, and their combination, were evaluated.

Findings

A total of 6729 pregnant women were enrolled, and the seroprevalence was 98.1%. Among 6350 newborns that were followed up, 49 were defined as having cCMV infection. In the screening test, the CMV DNA positivity rate remained similar from day 0 to day 5, increased slowly from day 6 to day 13, and became high in newborns beyond 13 days of birth. In the confirmatory testing, the positive rates increased significantly beyond day 21. For the 49 newborns with cCMV infection, the proportion of agreement between saliva and urine testing was poor. Upon evaluating alternative screening strategies, using saliva and urine screening with saliva and urine confirmation as the reference strategy, saliva screening with saliva and urine confirmation showed good diagnostic accuracy and feasibility, with sensitivity, specificity, positive predictive and negative predictive values of 85.7%, 100.0%, 100.0% and 99.9%, respectively.

Interpretation

In populations with high seroprevalence, saliva screening with saliva and urine confirmation might be an alternative strategy for screening cCMV infections. The suggested timeframes for screening and confirmation are within 13 (ideally 5) and 21 (ideally 13) days of birth, respectively.

Funding

National Natural Science Foundation of China, National Science and Technology Major Project of China and Merck & Co., Inc., Kenilworth, New Jersey, U.S.A.

Congenital Cytomegalovirus Infection: Epidemiology, Timely Diagnosis, and Management

Congenital cytomegalovirus (cCMV) infection is common because of the ubiquitous nature of the virus and the lack of an effective prevention strategy during pregnancy. Most infants with cCMV are asymptomatic, although a notable subset can have sequelae including, most commonly, sensorineural hearing loss and neurodevelopmental disability, which may not be present at birth. Timely screening for cytomegalovirus in the first weeks after birth is critical to appropriately diagnose congenital infection, evaluate affected infants, and determine the treatment course. Antiviral therapy with valganciclovir can optimize end hearing and neurodevelopmental outcomes in symptomatic infants. This review discusses the epidemiology and clinical manifestations of cCMV, targeted and universal screening approaches, and treatment and monitoring of infants with cCMV.

Manuscript title: Maternal CMV seroprevalence rate in early gestation and congenital cytomegalovirus infection in a Chinese population

BACKGROUND

Congenital human cytomegalovirus (CMV) infection remains largely unrecognized and underemphasized in medical practice. This study aimed to describe the maternal CMV seroprevalence rate in early gestation and congenital CMV infection in a Chinese population.

METHODS

This was a prospective cohort study that was conducted in three hospitals in China from 2015 through 2018. Pregnant women were enrolled in early gestation and followed up in middle and late gestation with serological testing. CMV serostatus was determined by IgG testing in serum during early gestation. Their newborns were screened and confirmed for cCMV infection by real-time PCR testing in both saliva and urine at two time points. The cCMV prevalence, maternal seroprevalence and associated factors were analyzed.

RESULTS

In China, the CMV seroprevalence was 98.11% (6602/6729, 95% CI: 97.76%-98.41%), and the cCMV prevalence was 1.32% (84/6350, 95% CI: 1.07%-1.64%). Over 98% of cCMV-positive newborns were from pregnant women who were seropositive in early gestation in China. The prevalence of cCMV infection in newborns from seropositive and seronegative pregnant women was similar (crude prevalence: 1.33% vs 0.82%, P=1.00; estimated prevalence: 1.29% vs 1.05%, P=0.42). Pregnant women who were under 25 years old or primiparous had a lower seroprevalence. Newborns from pregnant women under 25 years old or from twin pregnancies had a higher prevalence of cCMV infection.

CONCLUSION

In China, the cCMV prevalence was high, and the rates were similar in newborns from pregnant women who were seropositive and seronegative in early gestation. The vast majority of cCMV newborns were from seropositive mothers.Trial registration: ClinicalTrials.gov identifier: NCT02645396..

Saliva, a bodily fluid with recognized and potential diagnostic applications

Human whole saliva is a bodily fluid that can be obtained easily by noninvasive techniques. Specimens can be collected by the patient also at home in order to monitor health status and variations of several analytes of clinical interest. The contributions to whole saliva include secretions from salivary glands and, among others, from the gingival crevicular fluid that derives from the epithelial mucosa. Therefore, saliva is currently a relevant diagnostic fluid for many substances, including steroids, nonpeptide hormones, therapeutic drugs, and drugs of abuse. This review at first briefly describes the different contributions to whole saliva. A section illustrates the procedures for the collection, handling, and storage of salivary specimens. Another section describes the present use of whole saliva for diagnostic purposes and its specific utilization for the diagnosis of several local and systemic diseases. The final sections illustrate the future opportunities offered by various not conventional techniques with a focus on the most recent –omic investigations. It describes the various issues that have to be taken into account to avoid false positives and negatives, such as the strength of the experimental plan, the adequacy of the number of samples under study, and the proper choice of controls.

Sensitivity of Dried Blood Spot Testing for Detection of Congenital Cytomegalovirus Infection

IMPORTANCE

The sensitivity of dried blood spots (DBS) to identify newborns with congenital cytomegalovirus (cCMV) infection has not been evaluated in screening studies using the current, higher-sensitivity methods for DBS processing.

OBJECTIVE

To assess the sensitivity of DBS polymerase chain reaction (PCR) for newborn screening for cCMV infection using saliva as the reference standard for screening, followed by collection of a urine sample for confirmation of congenital infection.

DESIGN, SETTING, AND PARTICIPANTS

This population-based cohort study took place at 5 newborn nurseries and 3 neonatal intensive care units in the Minneapolis/Saint Paul area in Minnesota from April 2016 to June 2019. Newborns enrolled with parental consent were screened for cCMV using DBS obtained for routine newborn screening and saliva collected 1 to 2 days after birth. Dried blood spots were tested for CMV DNA by PCR at both the University of Minnesota (UMN) and the US Centers for Disease Control and Prevention (CDC). Saliva swabs were tested by CMV DNA PCR at the UMN laboratory only. Newborns who screened positive by saliva or DBS had a diagnostic urine sample obtained by primary care professionals, tested by PCR within 3 weeks of birth. Analysis began July 2019.

EXPOSURES

Detection of CMV from a saliva swab using a PCR assay.

MAIN OUTCOMES AND MEASURES

Number of children with urine-confirmed cCMV and the proportion of them who were CMV positive through DBS screening.

RESULTS

Of 12 554 individuals enrolled through June 2019 (of 25 000 projected enrollment), 56 newborns were confirmed to have cCMV (4.5 per 1000 [95% CI, 3.3-5.7]). Combined DBS results from either UMN or CDC had a sensitivity of 85.7% (48 of 56; 95% CI, 74.3%-92.6%), specificity of 100.0% (95% CI, 100.0%-100.0%), positive predictive value (PPV) of 98.0% (95% CI, 89.3%-99.6%), and negative predictive value (NPV) of 99.9% (95% CI, 99.9%-100.0%). Dried blood spot results from UMN had a sensitivity of 73.2% (95% CI, 60.4%-83.0%), specificity of 100.0% (100.0%-100.0%), PPV of 100.0% (95% CI, 91.4%-100.0%), and NPV of 99.9% (95% CI, 99.8%-99.9%). Dried blood spot results from CDC had a sensitivity of 76.8% (95% CI, 64.2%-85.9%), specificity of 100.0% (95% CI, 100.0%-100.0%), PPV of 97.7% (95% CI, 88.2%-99.6%), and NPV of 99.9% (95% CI, 99.8%-99.9%). Saliva swab results had a sensitivity of 92.9% (52 of 56; 95% CI, 83.0%-97.2%), specificity of 99.9% (95% CI, 99.9%-100.0%), PPV of 86.7% (95% CI, 75.8%-93.1%), and NPV of 100.0% (95% CI, 99.9%-100.0%).

CONCLUSIONS AND RELEVANCE

This study demonstrates relatively high analytical sensitivity for DBS compared with previous studies that performed population-based screening. As more sensitive DNA extraction and PCR methods continue to emerge, DBS-based testing should remain under investigation as a potential low-cost, high-throughput option for cCMV screening.

Timing of newborn hearing screening in the neonatal intensive care unit: implications for targeted screening for congenital cytomegalovirus infection

OBJECTIVE

To determine when infants in the neonatal intensive care unit (NICU) have the first hearing screen performed, and thus inform targeted testing for cytomegalovirus (CMV)-related hearing loss.

STUDY DESIGN

Retrospective review of electronic health records of infants admitted to a Level 4 outborn NICU and had a first hearing screen performed from 8/2016-8/2018.

RESULT

Among 1498 infants, 546 (36%) had a first hearing screen performed at age >21 days when a positive CMV PCR test cannot distinguish congenital from postnatal CMV acquisition. While most infants tested at >21 days of age were <34 weeks' gestational age (71%), 18% (n = 100) and 11% (n = 59) were ≥34 and ≥37 weeks' gestation, respectively.

CONCLUSION

Targeted CMV testing for failed hearing screen in the NICU is problematic as 36% of infants did not have a hearing screen performed before 21 days of age, supporting the need for CMV screening at NICU admission.

Cytomegalovirus infection during pregnancy: state of the science

Cytomegalovirus is the most common congenital infection, affecting 0.5-2% of all live births and the main nongenetic cause of congenital sensorineural hearing loss and neurological damage. Congenital cytomegalovirus can follow maternal primary infection or nonprimary infection. Sensorineurological morbidity is confined to the first trimester with up to 40-50% of infected neonates developing sequelae after first-trimester primary infection. Serological testing before 14 weeks is critical to identify primary infection within 3 months around conception but is not informative in women already immune before pregnancy. In Europe and the United States, primary infection in the first trimester are mainly seen in young parous women with a previous child younger than 3 years. Congenital cytomegalovirus should be evoked on prenatal ultrasound when the fetus is small for gestation and shows echogenic bowel, effusions, or any cerebral anomaly. Although the sensitivity of routine ultrasound in predicting neonatal symptoms is around 25%, serial targeted ultrasound and magnetic resonance imaging of known infected fetuses show greater than 95% sensitivity for brain anomalies. Fetal diagnosis is done by amniocentesis from 17 weeks. Prevention consists of both parents avoiding contact with body fluids from infected individuals, especially toddlers, from before conception until 14 weeks. Candidate vaccines failed to provide more than 75% protection for >2 years in preventing cytomegalovirus infection. Medical therapies such as cytomegalovirus hyperimmune globulins aim to reduce the risk of vertical transmission but 2 randomized controlled trials have not found any benefit. Valaciclovir given from the diagnosis of primary infection up to amniocentesis decreased vertical transmission rates from 29.8% to 11.1% in the treatment group in a randomized controlled trial of 90 pregnant women. In a phase II open-label trial, oral valaciclovir (8 g/d) given to pregnant women with a mildly symptomatic fetus was associated with a higher chance of delivering an asymptomatic neonate (82%), compared with an untreated historical cohort (43%). Valganciclovir given to symptomatic neonates is likely to improve hearing and neurological symptoms, the extent of which and the duration of treatment are still debated. In conclusion, congenital cytomegalovirus infection is a public health challenge. In view of recent knowledge on diagnosis and pre- and postnatal management, health care providers should reevaluate screening programs in early pregnancy and at birth.

Ethical and Public Health Implications of Targeted Screening for Congenital Cytomegalovirus

Congenital cytomegalovirus (cCMV) is the most common congenital infection and is associated with sensorineural hearing loss, developmental delays, and visual impairment. The clinical presentation of cCMV is variable, and the majority (80%-90%) of newborns will never manifest any clinical symptoms. Given the clinical heterogeneity of cCMV infection, it is challenging to identify which newborns may benefit from testing. Recently, certain states have implemented a targeted screening program in which newborns who fail the newborn hearing screen are tested for cCMV. Clinicians and legislative bodies have been propelled into debates about the ethical and moral permissibility of a targeted cCMV screening approach. Those who oppose this screening approach describe undue burden on patients, families, and the health care system because the majority of newborns who fail the newborn hearing screen and have cCMV will not go on to have any sequelae related to cCMV, including hearing loss. However, those who support this screening approach cite the importance of early detection and ongoing surveillance for hearing loss and developmental delays in this high-risk group of newborns. This debate will be considered by experts in the field.

Characterization of a universal screening approach for congenital CMV infection based on a highly-sensitive, quantitative, multiplex real-time PCR assay

The majority of congenital cytomegalovirus (cCMV) infections are asymptomatic at birth and therefore not diagnosed. Approximately 10–15% of these infants develop late-onset hearing loss and other developmental disorders. Implementation of a universal screening approach at birth may allow early initiation of symptomatic interventions due to a closer follow-up of infants at risk and offers the opportunity to consider treatment of late-onset disease. Real-time PCR assays for the detection of CMV DNA in buccal swab samples demonstrated feasibility and good clinical sensitivity in comparison to a rapid culture screening assay. Because most cCMV infections remain asymptomatic, a universal screening assay that stratifies CMV infected infants according to low and high risk of late-onset cCMV disease could limit the parental anxiety and reduce follow-up costs. We therefore developed and characterized a screening algorithm based on a highly-sensitive quantitative real-time PCR assay that is compatible with centralized testing of samples from universal screening and allows to determine CMV DNA load of saliva samples either as International Units (IU)/ml saliva or IU/10⁵ cell equivalents. 18 of 34 saliva samples of newborns that tested positively by the screening algorithm were confirmed by detection of CMV DNA in blood and/or urine samples obtained during the first weeks of life. All screening samples that could not be confirmed had viral loads of <2.3x10⁵ IU/ml saliva (median: 6.8x10³) or 1.3x10⁵ IU/10⁵ cell equivalents (median: 4.0x10²). The viral load of screening samples with confirmed cCMV infection ranged from 7.5x10² to 8.2x10⁹ IU/ml saliva (median: 9.3x10⁷) or 1.5x10² to 5.6x10¹⁰ IU/10⁵ cell equivalents (median: 3.5x10⁶). Clinical follow-up of these newborns with confirmed cCMV infection should reveal whether the risk of late-onset cCMV disease correlates with CMV DNA load in early life saliva samples and whether a cut-off can be defined identifying cCMV infected infants with or without risk for late-onset cCMV disease.