Cytomegalovirus infection during pregnancy: state of the science

Human Cytomegalovirus-IE1 induces neonate liver injury in transgenic mouse

Congenital human cytomegalovirus (HCMV) is a significant contributor to liver damage in infants and children. HCMV-encoded IE1 protein plays an important role in viral replication and disease progression. To investigate the effects IE1 on neonate liver, the transgenic mouse model (IE1 mice) and transcriptome sequencing were performed. The results showed that compared to wild-type mice, IE1 can cause liver injury by affecting drug metabolism, fatty acid metabolism, steroid hormone biosynthesis, and retinol metabolism. Furthermore, cytochrome P450 (CYP) enzymes family play a crucial role in liver metabolism disorder of IE1 mice. Combined with the results of the PPI analysis and qRT-PCR validation, Cyp4f39, Cyp3a44, and Cyp3a11 may be the key genes of IE1 causing liver injury. Overall, our study highlights the potential harmful effects of the HCMV IE1 protein on the neonatal liver, offering new insights into the mechanisms underlying liver injury associated with congenital HCMV infection.

Acute Severe Ulcerative Colitis and Cytomegalovirus During Pregnancy: A Case Report

This is the first case report of cytomegalovirus colitis following viral reactivation during pregnancy in a patient hospitalized for acute severe ulcerative colitis and treated with ganciclovir despite its teratogenic risk given her corticosteroid-refractory nature, with favorable outcomes after 3 years.

Health and economic evaluation of cytomegalovirus vaccination strategy among young women in China: a modelling study

Background

Congenital cytomegalovirus (cCMV) infection imposes a substantial economic burden on both families and society in China. There is currently a paucity of dynamic models to study cytomegalovirus (CMV) vaccination strategies for China's high-seroprevalence population (over 95%). Recent clinical trials demonstrated that the messenger RNA (mRNA) vaccine candidate, mRNA-1647, exhibited potential efficacy in both preinfection and postinfection contexts. This study aims to assess the cost-effectiveness of various CMV vaccination strategies for Chinese young women.

Method

An age-structured dynamic model was adopted, using Mathematica software, to simulate three strategies: (1) no vaccination (status quo); (2) pre-marriage vaccination (age 20-28 years); (3) reproductive-age vaccination (age 20-40 years). The vaccine was assumed to have 50% coverage and 50% efficacy for the first 5 years, with efficacy gradually decreasing over the next 15 years, costing US$300 per treatment course. This study period covers 2025-2050. Health outcomes included reductions in cCMV infection incidence, morbidity and mortality. We conducted cost-effectiveness, scenario and sensitivity analyses, discounting costs and disability-adjusted life years (DALYs) at 3% annually. The strategy would be considered cost-effective if the incremental cost-effectiveness ratio (ICER) was below China's 2023 per capita gross domestic product (US$12 675).

Results

By 2050, pre-marriage and reproductive-age vaccination strategies could prevent cCMV infection incidence by 38.8% (95% uncertainty interval [UI], 33.7% to 43.5%) and 43.3% (38.3% to 47.1%), respectively, with ICERs of US$4751 (4124 to 5378) and US$10 814 (10 290 to 11 338) per DALY averted compared with the status quo. However, the reproductive-age strategy is not cost-effective, with an ICER of US$25 553 (12 566 to 36 126) versus the pre-marriage strategy.

Conclusions

Prioritising pre-marriage vaccination could control cCMV infection in China. Our findings would inform public health policies and guide future research on optimising CMV vaccination strategies.

Is Neonatal Viremia a Possible Predictor of the Timing of Maternal Infection in Asymptomatic Congenital Cytomegalovirus Infection? A Retrospective Study

Background: Asymptomatic congenital cytomegalovirus (acCMV) infections represent 85-90% of all congenital CMV infection. The incidence of late-onset sequelae in these cases significantly contribute to the burden of CMV disease. The timing of maternal infection (TMI) has been identified as the main predictor of late-onset sequelae in acCMV infants, and follow-up programs in Europe are currently calibrated according to the TMI. Our aim was to evaluate neonatal viremia as a possible predictor of the TMI in acCMV infections. Methods: Plasma viral loads (PVLs) were assessed in the first month of life in a population of acCMV-infected newborns delivered by women who suffer a primary CMV infection during pregnancy. TMI was assigned to a trimester of pregnancy according to the maternal serological screening. PVLs were evaluated in relation to the TMI and gestational age (GA) at birth. Results: One hundred and ten newborns were, respectively, assigned to preconceptional (6.4%), 1st (27.3%), 2nd (38.2%), and 3rd (28.2%) trimester infections. Median neonatal PVLs values were significantly different between groups (p < 0.001). First-trimester infections exhibited significantly higher PVLs when compared with third-trimester ones (p < 0.001). Overall, PVLs showed an inverse correlation with GA at birth (p = 0.003). Conclusions: Median neonatal PVLs are significantly higher in 1st trimester infections if compared with 3rd trimester ones, but a wide overlap between PVL values prevent their possible use as a predictor of the TMI. In our population, a significant inverse relationship, mainly dependent on 1st and 2nd trimester infections, is demonstrated between PVLs and GA. Overall, fetal viremia is already decreasing weeks before the term of pregnancy.

Designing a novel multi-epitope antigen for diagnosing human cytomegalovirus infection: An immunoinformatics approach

Human cytomegalovirus (HCMV) infection can lead to congenital infections and severe complications, particularly in immunocompromised individuals. Current serological tests for diagnosing HCMV infection often face limitations in sensitivity and specificity. Developing multi-epitope antigens for serological assays offers the potential for enhancing diagnostic accuracy. This study aimed to design a novel multi-epitope antigen for HCMV infection diagnosis using immunoinformatic approaches. Five tegument proteins (universal protein resource [UniProt] ID: Po8318, Po6725, F5HC97, Q6RX10, and F5HC05) were selected based on their antigenic properties and literature review. Six linear B-cell epitopes were predicted within conserved regions of each antigen sequence and linked with appropriate linkers. The designed multi-epitope antigen underwent thorough evaluation for physicochemical properties, solubility, antigenicity, and cross-reactivity. Additionally, the three-dimensional structure of the antigen was predicted, refined, and validated. The nucleotide sequence of the designed antigen was optimized for successful expression in Escherichia coli and inserted into a pET23a (+) vector. Immunoinformatic analysis revealed that the multi-epitope antigen exhibits stability, antigenicity, and lacks cross-reactivity. Our findings suggest that this multi-epitope antigen is a promising candidate for diagnosing HCMV infection. However, further validation through laboratory testing is required to confirm its diagnostic efficacy.

Neuron-restricted cytomegalovirus latency in the central nervous system regulated by CD4+ T-cells and IFN-γ

All human herpesviruses establish latency following the resolution of the primary infection. Among these, α-herpesviruses HSV-1, HSV-2 and VZV establish latency in neurons, whereas neurons are not traditionally considered a site of latency for other herpesviruses. Using a combination of in vivo murine models and ex vivo human fetal tissues, we discovered that cytomegalovirus (CMV), a ubiquitous β-herpesvirus, can persist in neurons and that CD4+ T-cell-derived interferon-gamma is critical in restricting active viral replication in this cell type. Furthermore, we show that mouse CMV can establish latency in neurons and that CD4+ T-cells are essential in preventing viral reactivation. Our findings may have translational significance because human cytomegalovirus (HCMV) is the leading cause of congenital viral infections resulting in neurodevelopmental and neuroinflammatory lesions with long-term functional sequelae.

The Utility of Serologic TORCH Testing During Pregnancy for Maternal-related Versus Fetal-related Indications: A Retrospective Study

BACKGROUND

Clear guidelines have not been established about the utility of TORCH serology testing in women for whom TORCH infection is suspected according to clinical and laboratory manifestations during pregnancy. We aimed to compare rates of TORCH infections [specifically cytomegalovirus (CMV), Toxoplasma and rubella] in women who underwent TORCH serology testing due to maternal- versus fetal-related indications.

METHODS

This 10-year single-center retrospective study included all the women beyond 24 weeks of gestation who underwent TORCH serology testing due to maternal- or fetal-related indications. Maternal-related indications included fever, gastroenteritis, elevated liver enzymes and thrombocytopenia. Fetal-related indications included intrauterine growth restriction, polyhydramnios and oligohydramnios.

RESULTS

During the study period, 304 women underwent TORCH serology testing due to maternal-related indications and 771 due to fetal-related indications. For the maternal-related compared with the fetal-related indication group, maternal and congenital TORCH infections were more prevalent ( P = 0.015), specifically CMV ( P = 0.036). Eight (2.6%) of the women with maternal-related indications had a primary TORCH infection; 4 of them (50%) had concomitant congenital infections. Six (0.8%) of the women with fetal-related indications had a primary infection; none had a related congenital infection. Among the women with maternal-related indications, higher rates of maternal TORCH infection were found among those with thrombocytopenia (7.1%) and elevated liver enzymes (3.0%). During the study period, maternal-indicated TORCH testing detected 10.8% of neonates born with a confirmed TORCH infection.

CONCLUSIONS

The clinical yield of TORCH serology for nonspecific sonographic fetal features was low. Nonetheless, maternal-related indications should prompt testing for CMV and Toxoplasma infection.

Evaluation and Management of Congenital Cytomegalovirus Infection

The purpose of this review is to serve as an update on congenital cytomegalovirus (CMV) evaluation and management for obstetrician-gynecologists and to provide a framework for counseling birthing people at risk for or diagnosed with a primary CMV infection or reactivation or reinfection during pregnancy. A DNA virus, CMV is the most common congenital viral infection and the most common cause of nongenetic childhood hearing loss in the United States. The risk of congenital CMV infection from transplacental viral transfer depends on the gestational age at the time of maternal infection and whether the infection is primary or nonprimary. Although the risk of congenital CMV infection is lower with infection at earlier gestational ages, clinical sequelae are more severe with maternal infections earlier in gestation. At present, routine screening for maternal CMV infection is not recommended by U.S. guidelines. When maternal primary infection is confirmed in early pregnancy, emerging data support consideration of maternal antiviral therapy to prevent congenital CMV infection. When congenital CMV infection is confirmed, typically after an abnormal prenatal ultrasound result, there are more limited data on the utility of maternal antiviral therapy. Universal newborn screening for congenital CMV infection is not mandatory in most U.S. states at present. Newborns diagnosed with congenital CMV infection undergo an extensive evaluation to determine whether neurologic symptoms are present, which guides postnatal evaluation and management. In this review, we discuss the diagnosis and management of maternal CMV infection, the risk and diagnosis of congenital CMV infection, prevention and potential treatment of congenital CMV infection in utero, and neonatal congenital CMV infection diagnosis and management.

Diagnosis and management of congenital Cytomegalovirus: Critical Appraisal of Clinical Practice Guidelines

OBJECTIVES

To review the currently available Clinical Practice Guidelines regarding the diagnosis and management of Cytomegalovirus (CMV) infection in pregnancy.

METHODS

Medline, Turning Research into Practice (TRIP), Web of Science databases and scientific societies' websites were searched electronically up to April 2024. We included national and international Clinical Practice Guidelines regarding diagnosis, treatment and follow-up of CMV infection in pregnancy, published in English language. Quality assessment of the included guidelines was performed using the Appraisal of Guidelines for Research and Evaluation (AGREE) II tool.

RESULTS

Ten Clinical Practice Guidelines and two expert consensus statements were included. The review showed agreement among national and international guidelines about the diagnostic criteria for primary maternal CMV infection and about the gold standard for confirmation of fetal infection. Regarding treatment, only two societies recommended routine administration of Valaciclovir in case of primary infection in the clinical practing setting. Fetal surveillance including ultrasound and magnetic resonance imaging (MRI) in case of confirmed infection was found to be heterogeneous among the recommendations.

CONCLUSIONS

Although consensus was obtained regarding the diagnostic criteria for primary CMV infection in pregnancy, there was heterogeneity among Clinical Practice Guidelines with regards to other aspects of clinical management of CMV in pregnancy. In addition, some topics where not addressed in the current guidelines, including the treatment of non-confirmed fetal infection and the management of non-primary maternal infection. Recommendations regarding prevention of congenital CMV are rapidly evolving based on the new available evidence.

Universal screening and valacyclovir for first trimester primary cytomegalovirus: a cost-effectiveness analysis

BACKGROUND

Universal prenatal screening for cytomegalovirus is not currently recommended in the United States, as no effective interventions have previously been available. With growing evidence that treating maternal first trimester primary cytomegalovirus infections with valacyclovir reduces vertical transmission, universal screening may become an important tool in congenital cytomegalovirus prevention.

OBJECTIVE

This study examined the cost-effectiveness of a universal screening approach for maternal cytomegalovirus in the first trimester of pregnancy followed by valacyclovir treatment in positive cases for prevention of the sequelae of congenital cytomegalovirus.

STUDY DESIGN

A decision-analytic model was constructed to compare outcomes of universal screening and subsequent valacyclovir treatment in a theoretical cohort of 2,869,141 individuals, the estimated number of pregnant people in the United States who receive prenatal care by the first trimester. Individuals found to be immunoglobulin G positive, immunoglobulin M positive, and to have low immunoglobulin G avidity were considered to have primary cytomegalovirus infection and received valacyclovir. Outcomes included cases of vertical cytomegalovirus transmission, abortions, stillbirths, neonatal deaths, cases of hearing loss, cases of neurodevelopmental disabilities, costs, and quality-adjusted life years. Model inputs were derived from literature. Sensitivity analyses were performed via tornado analysis, univariable sensitivity analysis, and multivariable sensitivity analysis with Monte Carlo simulation.

RESULTS

In our study, universal screening in the first trimester for primary cytomegalovirus and subsequent treatment with valacyclovir in positive cases decreased adverse outcomes by preventing 2898 vertical transmissions, 94 abortions, 19 stillbirths, 11 neonatal deaths, 460 cases of hearing loss, and 263 cases of neurodevelopmental disability. Universal screening and subsequent treatment was the dominant strategy as it saved 242.2 million dollars and led to 3437 additional quality-adjusted life years. Tornado analysis demonstrated that there were no threshold values which would change the model results, when all variables were varied across a predetermined range. Univariable sensitivity analyses demonstrated that even with decreasing specificity of screening tests, decreasing maternal utility of neonatal hearing loss, and increasing the price of screening up to 17 times the current cost, universal screening remained the cost-effective strategy. Monte Carlo analysis demonstrated that the screening strategy remained cost-saving in 100% of trials.

CONCLUSION

Our results demonstrate that screening for first trimester primary cytomegalovirus may be a cost-saving intervention, as identification of cases allows for the provision of treatment, which in turn reduces vertical cytomegalovirus transmission and costly sequelae.

Prevalence and timing of prenatal ultrasound findings in cytomegalovirus-infected pregnancies

INTRODUCTION

To investigate the prevalence and timing of prenatal neurosonographic abnormalities after primary cytomegalovirus seroconversion by the first trimester of pregnancy. The additional value of magnetic resonance imaging (MRI) and the correlation between cytomegalovirus viral load in amniotic fluid and adverse neonatal outcomes were evaluated.

MATERIAL AND METHODS

A retrospective study between 2006 and 2022 examined data from 440 women with amniocentesis for periconceptional and first-trimester cytomegalovirus seroconversion. Cases with positive amniocentesis and subsequent follow-up were included. Prenatal neurosonography, MRI, and clinical outcomes were analyzed.

RESULTS

Out of 190 women included, 37% (n = 70) presented with a normal neurosonography. Patients exhibiting abnormal neurosonography findings showed higher viral loads in amniotic fluid compared to those with a normal neurosonography (p = 0.002). In 26% (n = 49) the first abnormal ultrasound sign was already picked up at amniocentesis, and the most common ones were echogenic bowels (49%) and periventricular echogenicity (43%). With increasing gestational age, the likelihood of a new abnormal neurosonography finding decreases. MRI discovered additional abnormalities in 14% (n = 10).

CONCLUSIONS

The results highlight the importance of combining diagnostic modalities, from amniocentesis to biweekly ultrasound monitoring and subsequent MRI evaluation, to capture the chronological progression and subsequent outcome of congenital cytomegalovirus.

Contribution of fetal blood sampling to determining the prognosis of congenital cytomegalovirus infections: a case-cohort study in Switzerland

BACKGROUND

Cytomegalovirus is responsible for the most common congenital infection, affecting 0.5% to 1.0% of live births in Europe. Congenital cytomegalovirus infection can be diagnosed during pregnancy by viral DNA amplification in the amniotic fluid, but the prognosis of fetuses without severe brain abnormalities remains difficult to establish on the basis of prenatal imaging alone.

OBJECTIVE

To identify predictors of moderate to severe symptomatic cytomegalovirus infection among fetal blood parameters and to propose an algorithm on the basis of these parameters and on prenatal imaging that would provide the best positive and negative predictive values.

STUDY DESIGN

Fetal blood sampling at 21-28 weeks gestation was performed in fetuses with congenital cytomegalovirus infection confirmed by amniocentesis after maternal infection in the first-trimester or periconceptional period. We compared the levels of hemoglobin, thrombocytes, γ-glutamyl transpeptidase, aspartate aminotransferase, alanine aminotransferase, β2-microglobulin, immunoglobulins G and M, and cytomegalovirus DNA viral loads in amniotic fluid and fetal blood between those with moderate to severe symptomatic infection and those with asymptomatic to mild infection (median follow-up of 36 months for live births).

RESULTS

Among 58 fetuses included, 25 (43%) had a moderate to severe symptomatic infection: 16 with severe cerebral abnormalities, 5 with multiple signs or symptoms at birth, 2 with bilateral sensorineural hearing loss, and 2 with neurodevelopmental delay. The values of thrombocytes, aspartate aminotransferase, β2 microglobulin, Immunoglobulin M, and cytomegalovirus viral loads differed significantly between fetuses with moderate to severe symptomatic infection and those with asymptomatic to mild infection. The optimal strategy to predict moderate to severe symptomatic infection was to first perform fetal brain imaging, followed by fetal blood sampling with the following cutoffs: thrombocytes <120,000/mL, viremia ≥5 log10/mL, and β2 microglobulin ≥12 mg/L). This recursive algorithm had a negative predictive value of 100% for moderately to severely symptomatic infection.

CONCLUSION

The combination of thrombocytes, β2-microglobulin, and cytomegalovirus viral load in fetal blood can be used for prognosis determination, particularly in cytomegalovirus-infected fetuses without severe brain abnormalities at the time of prenatal diagnosis. Future studies should evaluate whether these parameters remain useful in infected fetuses who have been treated with valacyclovir before fetal blood sampling.

Clinical Characteristics and Outcomes of Intrauterine Blood Transfusion (IUT) for Infectious Etiologies

OBJECTIVE

Congenital viral infection may result in fetal anemia and thrombocytopenia. While intrauterine blood transfusions (IUTs) are more commonly performed for Rh alloimmunization, reports using IUT for infection have varying success. Our primary objective was to characterize the outcomes of patients undergoing IUT for infectious etiologies at our center compared with Rh disease.

STUDY DESIGN

This was a case series of patients undergoing IUT from 2012-2023. Infectious etiologies were identified by maternal serologies and confirmed by amniotic fluid polymerase chain reactions (PCR). Clinical outcomes were obtained from electronic medical records.

RESULTS

During the study period, 70 patients underwent IUT, 34% (24/70) for Rh alloimmunization and 17% (12/70) for infection. Those with infectious etiologies were more likely to be diagnosed at earlier gestational ages (22 vs. 25 weeks, p = 0.04), with hydrops (75 vs. 33%, p = 0.03), and thrombocytopenia (27 ± 33 × 103 vs. 163 ± 112 × 103, p < 0.01). Perinatal death was significantly greater in cases of CMV (4/5, 80%) compared to parvovirus (1/7, 14%) or Rh alloimmunization (5/24, 21%) (p = 0.02).

CONCLUSION

Anemias and thrombocytopenias related to fetal infection may be indications for IUT. Compared with Rh alloimmunization, IUT in fetal infections was performed significantly earlier, and hydrops were more common at the time of IUT. In the case of CMV, greater rates of IUFD (80%) were observed. Patients should be counseled on the various outcomes by indication.

Cytomegalovirus infection of the fetal brain: intake of aspirin during pregnancy blunts neurodevelopmental pathogenesis in the offspring

BACKGROUND

Congenital cytomegalovirus (CMV) infections represent one leading cause of human neurodevelopmental disorders. Despite their high prevalence and severity, no satisfactory therapy is available and pathophysiology remains elusive. The pathogenic involvement of immune processes occurring in infected developing brains has been increasingly documented. Here, we have used our previously validated rat model of CMV infection of the fetal brain in utero to test whether the maternal administration of four different drugs with immunomodulatory properties would have an impact on the detrimental postnatal outcome of CMV infection.

METHODS

CMV infection of the rat fetal brain was done intracerebroventricularly. Each of the drugs, including acetylsalicylic acid (aspirin, ASA), a classical inhibitor of cyclooxygenases Cox-1 and Cox-2, the two key rate-limiting enzymes of the arachidonic acid-to-prostaglandins (PG) synthesis pathway, was administered to pregnant dams until delivery. ASA was selected for subsequent analyses based on the improvement in postnatal survival. A combination of qRT-PCR, mass spectrometry-based targeted lipidomics, immunohistochemistry experiments, monitoring of neurologic phenotypes and electrophysiological recordings was used to assess the impact of ASA in CMV-infected samples and pups. The postnatal consequences of CMV infection were also analyzed in rats knocked-out (KO) for Cox-1.

RESULTS

Increased PGE2 levels and increased proportions of Cox-1+ and Cox-2+ microglia were detected in CMV-infected developing brains. Maternal intake of ASA led to decreased proportion of Cox-1+ fetal, but not neonatal, microglia, while leaving the proportions of Cox-2+ microglia unchanged. Maternal intake of ASA also improved the key postnatal in vivo phenotypes caused by CMV infection and dramatically prevented against the spontaneous epileptiform activity recorded in neocortical slices from CMV-infected pups. In contrast with maternal intake of ASA, Cox-1 KO pups displayed no improvement in the in vivo phenotypes after CMV infection. However, as with ASA administration, the spontaneous epileptiform activity was dramatically inhibited in neocortical slices from CMV-infected, Cox-1 KO pups.

CONCLUSION

Overall, our data indicate that, in the context of CMV infection of the fetal brain, maternal intake of ASA during pregnancy improved CMV-related neurodevelopmental alterations in the offspring, likely via both Cox-1 dependent and Cox-1 independent mechanisms, and provide proof-of-principle for the use of ASA against the detrimental outcomes of congenital CMV infections.

Maternal Cytomegalovirus (CMV) Serology: The Diagnostic Limitations of CMV IgM and IgG Avidity in Detecting Congenital CMV Infection

INTRODUCTION

Congenital cytomegalovirus (cCMV) is a common congenital viral infection. Testing for cCMV usually begins with assessing maternal CMV serology, specifically IgM and IgG antibodies. A negative maternal CMV IgM suggests a low risk of recent maternal CMV infection, thereby suggesting a low risk of cCMV in the fetus. Consequently, cCMV is often ruled out when maternal CMV IgM is negative.

METHODS

In our perinatal autopsy and placental pathology database, we identified 5 cases of cCMV despite negative maternal CMV IgM results in the second trimester.

RESULTS

In all 5 cases, fetal abnormalities were first detected by ultrasound in the second trimester, prompting maternal CMV testing. Since second trimester maternal CMV IgM was negative in all cases, cCMV was considered unlikely, thus precluding further prenatal CMV testing in 4 of these cases. The diagnosis of cCMV was subsequently made through placental and/or autopsy examinations. Following this diagnosis, retrospective CMV serology and IgG avidity testing was performed on stored frozen first-trimester maternal blood samples in 3 cases. Among these, the first-trimester samples in 2 cases were IgG+, IgM+, and exhibited low IgG avidity, suggesting a primary maternal CMV infection around the time of conception. In the third case, both first and second-trimester maternal blood samples were IgG+, IgM-, and showed high IgG avidity, suggesting a non-primary maternal CMV infection (i.e., reactivation or reinfection of CMV).

CONCLUSION

A negative maternal CMV IgM in the second trimester cannot exclude cCMV infection. While CMV IgG avidity testing and analysis of stored frozen first-trimester maternal blood samples provide valuable insights, they have limitations. CMV PCR performed on amniotic fluid is a useful prenatal diagnostic tool. For cases of unexplained fetal abnormalities or death, autopsy and placental examination are recommended.

Clinical Practice Guidelines for the Management of Congenital Cytomegalovirus Infection in Japan 2023: Executive Summary

Congenital cytomegalovirus (cCMV) infection is the most common congenital infection in developed countries. Although a standard therapy has not yet been established, evidence for the management of cCMV infection has been accumulating. The first edition of the "Clinical Practice Guidelines for the Management of Congenital Cytomegalovirus Infection" was published in Japan in 2023. This summary outlines the clinical questions (CQs) in the guidelines, with reference to the Japanese Medical Information Distribution Service Manual. Overall, 20 CQs with statements regarding prenatal risk assessment, prevention and management at diagnosis (CQs 1-1-1-3), diagnosis (CQs 2-1-2-6), treatment (CQs 3-1-3-7) and follow-up requirements (CQs 4-1-4-4) have been discussed. For each statement, the levels of recommendation, evidence and consensus rates were determined. These guidelines will assist in the management of patients with cCMV infection.

Callosal Injuries in Cytomegalovirus Fetopathy: A Neurosonographic Study

INTRODUCTION

Among the fetal brain anomalies described in cases of congenital infection, callosal insults are rarely cited in medical literature. The aim of this study was to describe the rate and pattern of callosal injury in cytomegalovirus (CMV) fetopathy.

METHODS

This retrospective study included fetuses with confirmed CMV-PCR, assessed in a single center. Demographic data including maternal seroconversion info were collected. Dedicated US including neurosonography was performed, with high frequency probes, using TV route whenever feasible. Fetal brain biometry including callosal length and the corpus callosum (CC)/OFD ratio was performed. Length below the 5th centile or morphological abnormalities were considered abnormal. Brain and body morphology were thoroughly assessed, and any abnormal finding reported.

RESULTS

Seventy-two patients were included in our cohort. In 76% infection occurred in the 1st T or periconceptional. In 12 patients, the exact time of infection was inconclusive, including two cases of secondary infection. In 34.7%, a callosal anomaly was observed and it was never isolated. CNS abnormalities included: periventricular hyperechogenicity (PVHE) 55.5%, calcifications 52%, ventriculomegaly 33%, periventricular pseudocysts 31.4%, occipital cysts 22.2%, echogenic ganglionic eminence 30.5%, lentostriatal vasculopathy 26.4%, sulcation abnormalities 22.2%, cerebellar findings 18% and HC below -2 SD 18%. In 19 cases, the CC was short with calcifications in four. In one case, the insult was severe and in another the CC was absent. The most common association with CC insult was PVHE (56%) and calcifications (52%).

CONCLUSION

Although not referred as a classic brain structure affected by CMV infection, the CC was injured in one-third of our patients, including cases of late infection. The mechanism of disease and the prenatal patterns of callosal involvement in these cases appear to be different from the postnatal patterns and are not reversible. The presence of a callosal injury would imply a worse prognosis and significant increment to the risk of neurodevelopmental impairment.

Seroprevalence of cytomegalovirus among pregnant women in Singapore

BACKGROUND

Cytomegalovirus (CMV) is the most common congenital infection in pregnancy with potential long-term adverse effects on the fetus. There is limited data on CMV seroprevalence in pregnant women in Singapore, with last reported study dating back over two decades. We look at the latest CMV seroprevalence in antenatal population in Singapore.

METHODS

Between January 2021 and August 2021, 385 pregnant women receiving antenatal care at Singapore General Hospital were randomly selected for CMV IgG test to be performed on their blood samples collected during the first trimester of their pregnancies. Positivity for CMV IgG represents past exposure prior to pregnancy.

RESULTS

Overall CMV seroprevalence was 71.7% (276/385) (95% CI 067, 0.76, p value < 0.001). The trend of CMV IgG positivity increased with age, 68.3% (95% CI 0.60, 0.76, p value < 0.001) in those aged 20-29, 72.5% (95% CI 0.66, 0.78, p value < 0.001) in the 30-39 age group, and 79.0% (95% CI 0.67, 0.76, p value 0.012) in women over 40.

CONCLUSIONS

There is a declining trend in CMV seroprevalence among pregnant women in Singapore, which indicates that a substantial portion of this population faces the risk of primary maternal CMV infection during pregnancy. Emerging research suggests that prenatal treatment with valacyclovir effectively reduces the likelihood of vertical transmission. Considering this evidence, it is imperative to reevaluate the recommendations for universal maternal CMV screening during pregnancy.

In utero treatment of congenital cytomegalovirus infection with valganciclovir: an observational study on safety and effectiveness

BACKGROUND

The treatment of congenital cytomegalovirus (CMV) infection is usually administered to neonates after birth; however, it can be anticipated during the prenatal period by treating pregnant women in order to reduce the severity of the congenital disease. The most commonly used treatment for CMV during pregnancy is valaciclovir; however, valganciclovir has a higher potency against CMV and is the first choice for neonates with congenital CMV disease.

OBJECTIVES

We investigated neonatal and maternal safety of tertiary prevention in infected fetuses showing ultrasound features of infection using valganciclovir.

METHODS

Retrospective cohort study of pregnant women and their symptomatic infected fetuses taking valganciclovir, 3 × 450 mg per day. All fetuses presented at least one prenatal feature on ultrasound. We assessed fetal/neonatal and maternal safety, as well as neonatal efficacy of treatment. The main outcome was neutropenia. Secondary outcomes included other haematological side effects, symptoms at birth and neonatal CMV-PCR was positive.

RESULTS

Seventeen women with singleton pregnancies received valganciclovir from a median (IQR) of 27.1 (26.0-30.3) to 11.6 (6.5-12.9) weeks of gestation. No neonatal neutropenia was reported. One pregnancy was terminated for severe features. Three newborns (18%) were asymptomatic at birth, including one with negative CMV-PCR from blood and saliva. CMV-PCR was positive for 12/13 symptomatic newborns, with a median (IQR) log10 viral load of 3.36 (3.30-4.20), 4.03 (1.75-4.27) and 3.04 (0.00-3.40) log10 copies/mL in blood, urine and saliva, respectively.

CONCLUSIONS

Tertiary prevention by valganciclovir appears to be well tolerated for both fetus and mother. However, more extensive trials accompanied by long-term follow-up are needed.

Intrauterine Fetal Demise, Spontaneous Abortion and Congenital Cytomegalovirus: A Systematic Review of the Incidence and Histopathologic Features

The objective was to review the existing literature reporting on spontaneous abortion (SA) and intrauterine fetal demise (IUFD) associated with cytomegalovirus (CMV) infection. A review using standardized terminology such as 'intrauterine fetal death', 'congenital cytomegalovirus' and 'CMV' was performed using PubMed and Embase (Medline) using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) methodology. Twenty-one studies met inclusion criteria. CMV was identified as a potential or likely factor in a median of 7.1% of SA or IUFD in study cohorts. Of the studies, 11 used fetal remains, 18 used placenta, 6 used serum, and 1 used post-mortem dried blood spot as specimens for testing for CMV. Features commonly observed were fetal thrombotic vasculopathy, hydrops fetalis and chronic villitis. CMV is frequently noted in studies evaluating viral etiologies of SA or IUFD. Large population-based studies are needed to estimate the incidence of CMV-associated SA or IUFD. CMV and congenital CMV should be included on the differential diagnosis in all cases of SA or IUFD of unknown etiology.

Cytomegalovirus congenital infection: long-term outcomes in a valaciclovir treated population

OBJECTIVES

This case series aims to evaluate the long-term outcomes of congenital cytomegalovirus (CMV) infection in a population treated with valaciclovir during pregnancy. The study focuses on assessing the prevalence of long-term sequelae in infants with confirmed CMV fetal infection.

METHODS

A retrospective analysis was conducted on 33 pregnancies corresponding to 34 fetus with confirmed CMV congenital infection. They were followed from November 2004 to December 2020. Valaciclovir treatment was initiated after confirmation of fetal infection, and fetal outcomes were monitored through serial ultrasounds, neurosonography, and fetal magnetic resonance imaging (MRI). Postnatal assessments included: PCR confirmation, symptoms evaluation at birth, and long-term follow-up protocols for visual, auditory, and neurodevelopmental assessment.

RESULTS

Therapy was started at a median gestational age of 24 weeks. Of the 34 newborns 79.4 % were asymptomatic at birth. Median follow-up time was 6 years and 32.35 % developed long-term sequelae. Neurosensorial hearing loss (SNHL) was the predominant sequelae. In the cases which developed sequelae 54.5 % had imaging findings, and all with major findings developed long-term sequelae.

CONCLUSIONS

In our treated population we had a higher asymptomatic rate at birth comparing with a non-treated population, similar to those found in previous studies. We had a long-term sequelae rate of 32.35 %, similar to recent studies on non-treated population, although we registered a slightly lower rate of SNHL. A larger multicenter studies with a longer follow-up time, where treatment is started in the first trimester, is of the utmost importance, so we can truly understand the correlation between these imaging findings, therapy and long-term sequelae.

Reproductive Health in Kidney Transplant Recipients

Increasing number of women with kidney transplants are of reproductive age and desire successful pregnancies. Successful outcomes of pregnancy can be achieved with preconception counseling, education about contraception use, the timing of pregnancy (delaying by first year post-transplant), and the choice of immunosuppression medication. Ensuring stable renal function including optimized creatinine, proteinuria, and blood pressure increases successful outcomes. Pregnancy with kidney transplant has an increased risk of preeclampsia, gestational diabetes militeus, cesarean section, and preterm delivery. Multidisciplinary cooperation with high-risk obstetrics and transplant nephrologists is vital.

The Wide Spectrum of Presentations of Cytomegalovirus Infection in Immunocompetent Hosts: An Exhaustive Narrative Review

CMV is a ubiquitous DNA virus that establishes infection and results in 40-100% seropositivity. Viral replication occurs following an acquired primary infection (or reinfection) or by the reactivation of life-long latency. In immunocompetent patients, CMV infection is mostly asymptomatic or mild and self-limited. However, an extensive review of the literature published up to April 2024 reveals that despite immunocompetence, CMV can cause a very large variety of clinical syndromes in any part of the gastrointestinal tract (the most common pattern), the central or peripheral nervous system, and the eyes, as well as hematological, pulmonary, cardiac, and cutaneous disease. Not uncommonly, more than one system is involved, and though the disease is often self-limited, treatment with intravenous ganciclovir or oral valganciclovir may be required, and in isolated cases, fatalities may occur. Thus, a potential CMV infection should be considered in the differential of myriad syndromes in non-immunocompromised patients. Associated systemic symptoms (fever, sweats, and weight loss), lymphocytosis, and hepatitis are not uncommon and can be a useful clue. Some populations, such as critically ill patients in intensive care, pregnant women, elderly patients, and those with inflammatory bowel disease, may be more susceptible. Moreover, the potential of past, latent CMV infection (i.e., CMV seropositivity) to be associated with significant cardiovascular morbidity and all-cause mortality years later is intriguing and requires further study. All these data indicate the outstanding importance of developing a vaccine against CMV, which hopefully will become available in the foreseeable future. Meanwhile, a solid diagnosis of active CMV infection can be quickly established (or ruled out) by widely available serology tests and PCR amplification, and clinicians in all disciplines need to be more aware of the diverse guises of CMV infection and remember to consider it in any host, including an immunocompetent one.

Useful Clinical Criteria for Identifying Neonates with Congenital Cytomegalovirus Infection at Birth in the Context of an Expanded Targeted Screening Program

Cytomegalovirus (CMV) is the leading infectious cause of brain defects and neurological dysfunctions, including sensorineural hearing loss (SNHL). Targeted screening in neonates failing the hearing screen is currently recommended in Italy according to national guidelines. However, SNHL may not be present at birth; also, congenital CMV (cCMV) may manifest with subtle signs other than SNHL. Therefore, the inclusion of additional criteria for cCMV screening appears clinically valuable. Starting January 2021, we have implemented expanded targeted cCMV screening at our center, with testing in case of maternal CMV infection during pregnancy, inadequate antenatal care, maternal HIV infection or immunosuppression, birthweight and/or head circumference < 10th centile, failed hearing screen, and prematurity. During the first three years of use of this program (2021-2023), 940 (12.3%) of 7651 live-born infants were tested. The most common indication was birthweight < 10th centile (n = 633, 67.3%). Eleven neonates were diagnosed as congenitally infected, for a prevalence of 1.17% (95%CI 0.48-1.86) on tested neonates and of 0.14% (95%CI 0.06-0.23) on live-born infants. None of the cCMV-infected newborns had a failed hearing screen as a testing indication. Implementation of an expanded cCMV screening program appears feasible and of clinical value.

Evaluation of the In Vitro Capacity of Anti-Human Cytomegalovirus Antibodies to Initiate Antibody-Dependent Cell Cytotoxicity

In the setting of infectious diseases, antibodies show different functions beyond neutralizing activity. In this study, we investigated the activation of NK cells in vitro in the presence of human cytomegalovirus (HCMV)-specific antibodies and their potential role in the control of HCMV infection through antibody-dependent cell cytotoxicity (ADCC). Retinal pigmented epithelial cells (ARPE-19) infected with the HCMV strain VR1814 were co-cultured with cytokine-activated peripheral blood mononuclear cells (PBMCs) in the presence of sera collected from 23 HCMV-seropositive and 9 HCMV-seronegative donors. Moreover, 13 pregnant women sampled 3 and 6 months after HCMV primary infection and 13 pregnant women with pre-conception immunity were tested and compared. We determined the percentage of activated NK cells via the analysis of CD107a expression as a marker of degranulation. Significantly higher levels of NK-cell activation were observed using 1/100 and 1/10 dilutions of sera from HCMV-seropositive individuals, and when cells were infected for 96 and 120 h, suggesting that NK cells are activated by antibodies directed against late antigens. In the absence of serum NK cells, activation was negligible. In seropositive subjects, the median percentages of CD107a-positive NK cells in the presence of autologous serum and pooled HCMV-positive serum were similar (14.03% [range 0.00-33.56] and 12.42% [range 1.01-46.00], respectively), while NK-cell activation was negligible using an HCMV-negative serum pool. In HCMV-seronegative subjects, the median percentage of activated NK cells was 0.90% [range 0.00-3.92] with autologous serum and 2.07% [0.00-5.76] in the presence of the HCMV-negative serum pool, while it was 8.97% [0.00-26.49] with the pool of HCMV-positive sera. NK-cell activation using hyperimmune globulin is comparable to what is obtained using autologous serum. Sera from subjects at 3 and 6 months post primary infection showed a lower capacity of NK-cell activation than sera from subjects with past infection (p < 0.001). NK activation against HCMV-infected epithelial cells is dependent on the presence of HCMV-specific antibodies. This serum activity increases with time after the onset of HCMV infection. The protective role of NK-cell activation by HCMV-specific serum antibodies should be verified in clinical settings.

Human cytomegalovirus and neonatal infection

Human cytomegalovirus is an ancient virus that has co-evolved with humans. It establishes a life-long infection in suspectable individuals for which there is no vaccination or cure. The virus can be transmitted to a developing fetus in seropositive pregnant women, and it is the leading cause of congenital infectious disease. While the majority of infected infants remain asymptomatic at birth, congenital cytomegalovirus infection can lead to substantial long-term neurodevelopmental impairments in survivors, resulting in considerable economic and social hardships. Recent discoveries regarding cytomegalovirus pathophysiology and viral replication cycles might enable the development of innovative diagnostics and therapeutics, including an effective vaccine. This Review will detail our understanding of human cytomegalovirus infection, with an in-depth discussion regarding the viral genome and transcriptome that contributes to its pathophysiology. The neonate's clinical course will also be highlighted, including maternal and neonatal testing, treatment recommendations, and long-term outcomes.

Congenital Cytomegalovirus Infection With Isolated "Minor" Lesions at Fetal Magnetic Resonance Imaging: Long-Term Neurological Outcome

BACKGROUND

The prognostic relevance of fetal/early postnatal magnetic resonance (MR) imaging (MRI) isolated "minor" lesions in congenital cytomegalovirus (CMV) infection is still unclear, because of the heterogeneity of previously reported case series. The aim of this study was to report the imaging and long-term clinical follow-up data on a relatively large cohort of infected fetuses.

METHODS

Among 140 CMV-infected fetuses from a single-center 12-year-long fetal MRI database, cases that showed isolated "minor" lesions at MRI, mainly represented by polar temporal lesions, were selected. MRI features were described, and clinical follow-up information was collected through consultation of medical records and telephone interview to establish the auditory and neurological outcome of each patient.

RESULTS

Thirty-six cases were included in the study. The frequency of "minor" lesions increased progressively with ongoing gestational age in cases who underwent serial MR examination; 31% of cases were symptomatic at birth for unilateral altered auditory brainstem response. At long-term clinical follow-up, performed in 35 patients at a mean age of 64.5 months (range: 25 to 138), 43% of patients were asymptomatic and 57% presented with mild/moderate disability including hearing loss (34%), unilateral in all cases but one (therefore classified as severe), and/or minor cognitive and behavioral disorders (49%).

CONCLUSIONS

Descriptive analysis of the type and modality of occurrence of "minor" lesions suggests performing serial fetal/postnatal MR examinations not to miss later-onset lesions. Follow-up data from the present cohort, combined with maternal/fetal factors and serologic-laboratory parameters may contribute to improve prenatal and neonatal period counselling skills.

[Implementation of screening for cytomegalovirus congenital infection in a French type 3 maternity]

OBJECTIVES

Congenital cytomegalovirus (CMV) infection is the most common congenital infection and the leading cause of infectious neurosensorial disability in newborns. We wanted to organize the management of women from the beginning of pregnancy allowing access to antenatal treatment with valaciclovir, recognized since 2020 as limiting materno-fetal transmission. To this end, we set up and evaluated the interest of systematic screening for CMV infection in our maternity. We wanted to organize care for women from the very start of pregnancy.

METHODS

Retrospective and comparative descriptive study carried out at the CHRU de Limoges from July 2017 to December 2019 (targeted screening), then from January 2020 to June 2022, during which period we implemented systematized screening by iterative serologies at the 3rd, 6th, 8th months and before delivery. Our main evaluation criteria were the seroprevalence of CMV infection and the rate of congenital infection. We then described our cases of infection (primary or secondary) during pregnancy.

RESULTS

CMV seroprevalence in our pregnant women increased significantly from 52.7% (779/1478 women screened) to 58.4% (3852/6599 women screened) between the 2 study periods (P=0.04). We diagnosed 11 infections during the first part of the study vs. 27 during the second, with a significant increase in primary infections from 0.14% (9/6524 births) to 0.37% (24/6426 births) (P=0.008). Only 3 secondary infections were diagnosed during the second study period. The rate of congenital infections remained stable between the 2 study periods (6 children/6524=0.09% vs. 8 children/6426=0.12%; P=0.57).

CONCLUSION

Our results confirmed the interest of screening for CMV infection, while modifying the screening strategy we had initiated.

Long-term follow-up of a series of 24 congenital CMV-infected babies with false negative amniocentesis

BACKGROUND

Congenital CMV infection is the most common congenital infection worldwide and a major cause of neurological impairment and sensorineural hearing loss. Fetal CMV infection is confirmed by a positive PCR test in the amniotic fluid (amniocentesis performed after 18-20 weeks of gestation and at least 8 weeks after maternal infection). However, despite a negative antenatal CMV PCR result, some newborns can be tested positive at birth. Although not widely documented, the prognosis for these babies appears to be good.

OBJECTIVES

The aim of this study is to evaluate the long-term prognosis of fetuses with a false-negative AFS for cCMV, with a minimum follow-up period of 6 years.

STUDY DESIGN

This is a retrospective cohort study of false-negative amniocentesis reported at the CUB-Hôpital Erasme and Hôpital CHIREC in Brussels between 1985 and 2017.

RESULTS

Of the 712 negative CMV PCR amniocenteses, 24 had a CMV PCR positive at birth. The false negative rate was 8.6 %. Of the 24 cases, 9 primary maternal infections occurred in the first trimester, 14 in the second trimester and 1 in the third trimester. Among the 24 children, 2 had symptoms at birth (hyperbilirubinemia and left paraventricular cysts), but all had normal follow-up (minimum 4 years, mean 16,6 years).

DISCUSSION

Only 2 cases could be explained by early amniocentesis. Among the others, the false-negative results could be attributed to a low viral load, a delayed infection or, less likely, to a sample degradation.

CONCLUSION

Despite the false-negative results, all 24 children had a normal long-term follow-up.

Cytomegalovirus DNA Loads in Organs of Congenitally Infected Fetus

Congenital cytomegalovirus (cCMV) infection poses significant risks to fetal development, particularly affecting the nervous system. This study reports a fetal autopsy case, examining cCMV infection and focusing on CMV DNA measurements in various fetal organs before formalin fixation, a novel approach for comprehensive CMV DNA evaluations in fetal organs affected by cCMV. A 20-week-old male fetus was diagnosed with cCMV following the detection of CMV DNA in ascites obtained via abdominocentesis in utero. After the termination of pregnancy, multiple organs of the fetus, including the cerebrum, thyroid gland, heart, lungs, liver, spleen, kidneys, and adrenal glands, were extracted and examined for CMV DNA loads using a real-time polymerase chain reaction. Histopathological examination involved hematoxylin-eosin and CMV-specific immunostaining. A correlation was found between CMV DNA loads and pathology, with higher CMV-infected cell numbers observed in organs positively identified with both staining methods, exhibiting CMV DNA levels of ≥1.0 × 104 copies/mL, compared to those detected solely by CMV-specific immunostaining, where CMV DNA levels ranged from 1.0 × 103 to 1.0 × 104 copies/mL. These results highlight a quantifiable relationship between the organ infection extent and CMV DNA concentration, providing insights into cCMV pathogenesis and potentially informing future diagnostic and therapeutic strategies for cCMV infection.

Consensus recommendation for prenatal, neonatal and postnatal management of congenital cytomegalovirus infection from the European congenital infection initiative (ECCI)

Congenital cytomegalovirus (cCMV) infection carries a significant burden with a 0.64% global prevalence and a 17-20% chance of serious long-term effects in children. Since the last guidelines, our understanding, particularly regarding primary maternal infections, has improved. A cCMV guidelines group was convened under the patronage of the European Society of Clinical Virology in April 2023 to refine these insights. The quality and validity of selected studies were assessed for potential biases and the GRADE framework was employed to evaluate quality of evidence across key domains. The resulting recommendations address managing cCMV, spanning prevention to postnatal care. Emphasizing early and accurate maternal diagnosis through serological tests enhances risk management and prevention strategies, including using valaciclovir to prevent vertical transmission. The guidelines also strive to refine personalized postnatal care based on risk assessments, ensuring targeted interventions for affected families.

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.

Is a Higher Amniotic Fluid Viral Load Associated with a Greater Risk of Fetal Injury in Congenital Cytomegalovirus Infection-A Systematic Review and Meta-Analysis

Background: Numerous studies have aimed to predict prenatal and neonatal outcomes for pregnancies complicated by congenital cytomegalovirus (CMV). Presently, assessing CMV severity prenatally relies largely on fetal imaging. A controversy exists regarding CMV viral load (VL) and its association with fetal and neonatal sequelae. Objective: To perform a systematic review and meta-analysis investigating the association between CMV DNA VL in amniotic fluid and fetal and neonatal outcomes in pregnancies with congenital CMV. Results: All cohort, case-control and observational studies that compared outcomes of fetuses with congenital CMV and provided information on individual patient CMV VL quantified in copies per milliliter (c/mL) from inception to January 2023 were included, with no geographical or language restrictions. A total of 1251 citations were reviewed with eight studies meeting inclusion criteria and included in meta-analysis. Affected pregnancies had a higher VL in the amniotic fluid compared to those unaffected with a mean difference of 2.2e+7 (range 1.5e+7 to 2.8e+7). In subgroup analysis, the VL was significantly higher in the fetuses, with imaging findings related to CMV compared to asymptomatic fetuses with a mean difference of 4.1e+7 (95% CI 2.8e+7-5.4e+7). However, among babies with congenital CMV, the VL was not significantly different between symptomatic and asymptomatic babies. Conclusions: Amniotic fluid CMV VL is associated with fetal sequalae in congenital CMV, with a higher VL conferring a greater risk for prenatal injury.

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.

Counseling in fetal medicine: Congenital cytomegalovirus infection

Although the clinical work-up of CMV in pregnancy has gradually become more accurate, counseling for CMV is still challenging. Despite the potential feasibility of universal prenatal serological screening, its introduction in prenatal diagnosis continues to raise concerns related to its real cost-effectiveness. Contextually, anticipating the confirmation of fetal infection earlier in pregnancy is one of the most pressing issues to reduce the parental psychological burden. Amniocentesis is still the gold standard and recent data have demonstrated that it could be performed before 20 weeks of gestation, provided that at least 8 weeks have elapsed from the presumed date of maternal seroconversion. New approaches, such as chorionic villus sampling (CVS) and virome DNA, even if not yet validated as confirmation of fetal infection, have been studied alternatively to amniocentesis to reduce the time-interval from maternal seroconversion and the amniocentesis results. Risk stratification for sensorineural hearing loss (SNHL) and long-term sequelae should be provided according to the prognostic predictors. Nevertheless, in the era of valacyclovir, maternal high-dose therapy, mainly for first trimester infections, can reduce the risk of vertical transmission and increase the likelihood of asymptomatic newborns, but it is still unclear whether valacyclovir continues to exert a beneficial effect on fetuses with positive amniocentesis. This review provides updated evidence-based key counseling points with GRADE recommendations.

Congenital CMV infection in a Brazilian neonatal intensive care unit: high prevalence among twin newborns

BACKGROUND

Cytomegalovirus (CMV) is one of the most important pathogens associated with congenital infection worldwide. Most congenital CMV-infected infants are asymptomatic at birth; however, some can develop delayed sequelae, especially hearing loss.

METHODS

This study aimed to investigate the prevalence of congenital CMV infection in a neonatal intensive care unit in a low-income region of Brazil. The objectives extended to identifying associated factors, assessing the clinical status of infected newborns, and undertaking a two-year follow-up to discern potential long-term consequences in the affected infants. This cross-sectional prospective study enrolled newborns up to three weeks of life requiring intensive medical care. We employed a convenience sampling method to include 498 newborns and 477 mothers in the study. Categorical variables underwent analysis employing Fisher's exact test, whereas the examination of continuous variables involved the Mann‒Whitney test.

RESULTS

CMV DNA was detected in saliva/urine samples from 6 newborns (1.21%), confirming congenital infection. We noted a significantly greater incidence (OR: 11.48; 95% CI: 2.519-52.33; p = 0.0094) of congenital infection among twins (7.14%) than among nontwins (0.66%). The twin patients exhibited discordant infection statuses, suggesting that only one of the babies tested positive for CMV. Most of the infected children were born to mothers who initiated sexual activity at a younger age (p = 0.0269). Only three out of the six newborns diagnosed with CMV infection underwent comprehensive clinical assessments and received continuous follow-up until they reached two years of age. Only one of the children had weight and height measurements below the norm for their age, coupled with developmental delays.

CONCLUSIONS

The prevalence of congenital CMV infection among newborns admitted to the NICU was low and similar to that in the general population. However, we found a significantly greater incidence of congenital CMV infection in twins than in singletons. Interestingly, the twin-infected patients exhibited discordant infection statuses, suggesting that CMV was present in only one of the babies. We also found that most of the infected children were born to mothers who initiated sexual activity at a younger age. Diagnostic accessibility and comprehensive surveillance programs are imperative for effectively managing and preventing congenital CMV infections.

Human neural progenitor cell models to study the antiviral effects and neuroprotective potential of approved and investigational human cytomegalovirus inhibitors

Human cytomegalovirus (HCMV) is the viral leading cause of congenital defects in newborns worldwide. Many aspects of congenital CMV (cCMV) infection, which currently lacks a specific treatment, as well as the main determinants of neuropathogenesis in the developing brain during HCMV infection are unclear. In this study, we modeled HCMV infection at different stages of neural development. Moreover, we evaluated the effects of both approved and investigational anti-HCMV drugs on viral replication and gene expression in two different neural progenitor cell lines, i.e., human embryonic stem cells-derived neural stem cells (NSCs) and fetus-derived neuroepithelial stem (NES) cells. Ganciclovir, letermovir, nitazoxanide, and the ozonide OZ418 reduced viral DNA synthesis and the production of infectious virus in both lines of neural progenitors. HCMV infection dysregulated the expression of genes that either are markers of neural progenitors, such as SOX2, NESTIN, PAX-6, or play a role in neurogenesis, such as Doublecortin. Treatment with antiviral drugs had different effects on HCMV-induced dysregulation of the genes under investigation. This study contributes to the understanding of the molecular mechanisms of cCMV neuropathogenesis and paves the way for further consideration of anti-HCMV drugs as candidate therapeutic agents for the amelioration of cCMV-associated neurological manifestations.

The Auditory Pathway in Congenitally Cytomegalovirus-Infected Human Fetuses

Congenital cytomegalovirus (CMV) infection is the main cause of non-hereditary sensorineural hearing loss (SNHL). In order to shed light on SNHL pathophysiology, we examined the auditory pathway in CMV-infected fetuses; the temporal lobe, in particular the auditory cortex, and the inner ear. We investigated both inner ears and temporal lobes of 20 human CMV-infected fetuses at 21 weeks of gestation. As a negative group, five fetuses from spontaneous miscarriages without CMV infection were studied. Inner ears and temporal lobes were histologically examined, immunohistochemistry for CMV and CMV-PCR were performed. On the auditory cortex, we evaluated the local microglial reaction to the infection. CMV-positive cells were found in 14/20 brains and the damage was classified as severe, moderate, or mild, according to histological features. Fetuses with severe brain damage had a statistically higher temporal lobe viral load and a higher number of activated microglial cells in the auditory cortex compared to fetuses with mild brain damage (p: 0.01; p: 0.01). In the inner ears, the marginal cells of the stria vascularis were the most CMV positive. In our study, CMV affected the auditory pathway, suggesting a tropism for this route. In addition, in the auditory cortex, microglial activation may favor further tissue damage contributing to hearing loss.

Cytomegalovirus infection during pregnancy: cross-sectional survey of knowledge and prevention practices of healthcare professionals in French-speaking Switzerland

BACKGROUND

Lack of Cytomegalovirus (CMV) knowledge among healthcare professionals has been proven to be the main threat to pregnant women's awareness, preventing them from reducing the risk of infection. The aims of this study were to assess the knowledge and practices of French-speaking Swiss perinatal professionals in terms of CMV prevention, as well as the sociodemographic-professional factors that influence them.

METHODS

This observational study used a cross-sectional design to collect data-via an anonymous electronic questionnaire in French distributed to gynecologists-obstetricians, general practitioners and midwives via various channels: e-mails and social networks of partner centers, professional associations, and conferences. The 41-item questionnaire collected data on sociodemographic and professional characteristics, general CMV knowledge, national recommendation knowledge and prevention practices. Univariable and multivariable analyses were performed.

RESULTS

A total of 110 gynecologist-obstetricians, 5 general practitioners and 226 midwives participated in the study. While more than 80% of practitioners were familiar with protective hygiene measures, significant gaps were highlighted concerning the transmission routes, as well as the signs of short- and long-term congenital CMV infection. Regarding practice, 63.3% of participants provided information on CMV to their patients, mainly during the first antenatal visit. Among those who did not, lack of knowledge and forgetfulness were the two main reasons cited. Concerning systematic screening, 45.7% of participants offered it to their patients, and 37.3% only offered it to "at risk" groups. The existence of national guidelines on CMV was known by 62.0% of participants. Multivariable analysis revealed that working as a gynecologist-obstetrician was independently associated with higher score of preventive practices, while performing ultrasound or preconception consultations was independently associated with a higher score of general CMV knowledge, and working in a university hospital was independently associated with a higher score of Swiss recommendation knowledge. A level of training higher than the basic medical or midwifery diploma and participation in fetal medicine symposia both promote a higher score of CMV knowledge and prevention practices in line with current recommendations.

CONCLUSION

This study confirms the significant gaps in CMV knowledge among French-speaking Swiss caregivers along with the heterogeneity of their prevention practices. To raise awareness among pregnant women and reduce the burden of congenital CMV infections, improving professional knowledge through access to specific training and standardizing practices should be a national priority.

Genetic Counseling of Fetal Microcephaly

Fetal microcephaly is a small head with various losses of cerebral cortical volume. The affected cases may suffer from a wide range in severity of impaired cerebral development from slight to severe mental retardation. It can be an isolated finding or with other anomalies depending on the heterogeneous causes including genetic mutations, chromosomal abnormalities, congenital infectious diseases, maternal alcohol consumption, and metabolic disorders during pregnancy. It is often a lifelong and incurable condition. Thus, early detection of fetal microcephaly and identification of the underlying causes are important for clinical staff to provide appropriate genetic counseling to the parents and accurate management.

Decoding human cytomegalovirus for the development of innovative diagnostics to detect congenital infection

Cytomegalovirus is the most common cause of congenital infectious disease and the leading nongenetic etiology of sensorineural hearing loss. Although most infected neonates are asymptomatic at birth, congenital cytomegalovirus infection is responsible for nearly 400 infant deaths annually in the United States and may lead to significant long-term neurodevelopmental impairments in survivors. The resulting financial and social burdens of congenital cytomegalovirus infection have led many medical centers to initiate targeted testing after birth, with a growing advocacy to advance universal newborn screening. While no cures or vaccines are currently available to eliminate or prevent cytomegalovirus infection, much has been learned over the last five years regarding disease pathophysiology and viral replication cycles that may enable the development of innovative diagnostics and therapeutics. This Review will detail our current understanding of congenital cytomegalovirus infection, while focusing our discussion on routine and emerging diagnostics for viral detection, quantification, and long-term prognostication. IMPACT: This review highlights our current understanding of the fetal transmission of human cytomegalovirus. It details clinical signs and physical findings of congenital cytomegalovirus infection. This submission discusses currently available cytomegalovirus diagnostics and introduces emerging platforms that promise improved sensitivity, specificity, limit of detection, viral quantification, detection of genomic antiviral resistance, and infection staging (primary, latency, reactivation, reinfection).

Knowledge of cytomegalovirus and available prevention strategies in pregnancy: a cross-sectional study in Portugal

OBJECTIVE

Maternal and fetal congenital infection by cytomegalovirus (CMV) during pregnancy is the leading infectious cause of neurologic impairment and hearing loss. Efforts at limiting CMV exposure are based on hygienic measures. This study assessed the relationship between CMV knowledge and pregnant women's time perspective as per the Zimbardo Time Perspective Inventory (ZTPI) scale.

METHODS

We conducted a prospective descriptive study at a secondary-care Portuguese hospital between October to November 2021. All consecutive pregnant women in antenatal third-trimester appointments were included. The questionnaire included: sociodemographic data, knowledge about CMV, and the ZTPI scale, validated to our population. The number of correct answers in the knowledge section of the questionnaire was tallied to determine the individual knowledge score (KS). We investigated patients subjective perceptions of CMV infection during pregnancy, CMV knowledge, and CMV serologic status of pregnant women.

RESULTS

We enrolled 96 pregnant women. 81.0% had not previously heard about CMV and only 8.8% had heard about it through their obstetrician. No significant association between awareness of CMV and education level was detected. 16.0% of pregnant women declared that they were aware of the hygienic measures for CMV. The CMV serology was performed in 21.3% of those enrolled in the preconception assessment, and 13.8% proved to be immune. From the time perspective, half of the women displayed a future-oriented attitude. Future-oriented women had significantly higher KS. No significant association was found between KS and education level, age, or previous pregnancy. There was a significant association between KS and women that work in health care.

CONCLUSIONS

Most patients had no knowledge of CMV. Being a medical professional and having a future-oriented outlook increases knowledge about CMV. Primary health care and obstetrics doctors may play a crucial role in informing pregnant women of antenatal appointments. The CMV serology coverage is scarce in this sample. This study constitutes a first step toward raising the awareness of the general population about CMV.

Comparison of two serological screening strategies for cytomegalovirus primary infection in the first trimester of pregnancy

INTRODUCTION

CMV serology screening in the first trimester pregnancy is based on IgG and IgM testing followed by IgG avidity in cases with positive IgM. However, the sensitivity of this strategy to diagnose maternal primary infection has been questioned. The objective of the study was to compare this strategy 1 with a strategy 2 consisting of running avidity test on all samples with positive IgG (ignoring IgM results) using fully automated current generation CMV IgG, IgM and IgG avidity assays.

POPULATION AND METHODS

1516 consecutive pregnant women between 12 and 14 weeks were screened in one maternity. Strategy 1 was done prospectively with LIAISON® CMV IgG II and LIAISON® CMV IgM II, followed by LIAISON® CMV IgG Avidity II and VIDAS® CMV IgG avidity II testing in cases with positive or equivocal IgM. Strategy 2 was done retrospectively on the same population and consisted of running avidity with the LIAISON® CMV IgG Avidity II in all samples with positive IgG.

RESULTS

The sensitivity to diagnose a confirmed or a possible maternal primary infection in the first trimester was 91.6 % and 83 % for strategy 1 and 2 respectively (p > 0.99). Strategy 1 missed one possible primary infection and strategy 2 missed 2 confirmed primary infection. Inconclusive results happened in 0 and 0.7 % of samples with strategy 1 and 2 respectively.

CONCLUSION

This study suggests that strategy 1 has better sensitivity and practicability than strategy 2. However, to achieve a good performance with strategy 1, using highly sensitive IgM assay is mandatory.

Anti-CMV therapy, what next? A systematic review

Human cytomegalovirus (HCMV) is one of the main causes of serious complications in immunocompromised patients and after congenital infection. There are currently drugs available to treat HCMV infection, targeting viral polymerase, whose use is complicated by toxicity and the emergence of resistance. Maribavir and letermovir are the latest antivirals to have been developed with other targets. The approval of letermovir represents an important innovation for CMV prevention in hematopoietic stem cell transplant recipients, whereas maribavir allowed improving the management of refractory or resistant infections in transplant recipients. However, in case of multidrug resistance or for the prevention and treatment of congenital CMV infection, finding new antivirals or molecules able to inhibit CMV replication with the lowest toxicity remains a critical need. This review presents a range of molecules known to be effective against HCMV. Molecules with a direct action against HCMV include brincidofovir, cyclopropavir and anti-terminase benzimidazole analogs. Artemisinin derivatives, quercetin and baicalein, and anti-cyclooxygenase-2 are derived from natural molecules and are generally used for different indications. Although they have demonstrated indirect anti-CMV activity, few clinical studies were performed with these compounds. Immunomodulating molecules such as leflunomide and everolimus have also demonstrated indirect antiviral activity against HCMV and could be an interesting complement to antiviral therapy. The efficacy of anti-CMV immunoglobulins are discussed in CMV congenital infection and in association with direct antiviral therapy in heart transplanted patients. All molecules are described, with their mode of action against HCMV, preclinical tests, clinical studies and possible resistance. All these molecules have shown anti-HCMV potential as monotherapy or in combination with others. These new approaches could be interesting to validate in clinical trials.

Congenital cytomegalovirus infection: the state of the art and future perspectives

Congenital cytomegalovirus (cCMV) infection is the most common congenital infection, with an estimated incidence of approximately one in 200 infants in high-income settings. Approximately one in four children may experience life-long consequences, including sensorineural hearing loss and neurodisability. Knowledge regarding prevention, diagnosis, and treatment increased in the recent years, but some challenges remain. In this review, we tried to summarize the current knowledge on both the obstetrical and pediatric areas, while also highlighting controversial aspects and future perspectives. There is a need to enhance awareness among the general population and pregnant women through specific information programs. Further research is needed to better define the classification of individuals at birth and to have a deeper understanding of the long-term outcomes for so defined children. Finally, the availability of valaciclovir medication throughout pregnancy, where appropriate, has prompted the assessment of a universal serological antenatal screening. It is recommended to establish a dedicated unit for better evaluation and management of both mothers and children.

Cell-mediated and humoral immune responses to human cytomegalovirus in pregnant women with vertically transmitted infection following primary infection: A case report

Human cytomegalovirus (HCMV) is the major cause of neurological sequelae in infants. Immune control of primary HCMV infection appears to depend on the interaction between humoral and cell-mediated immune responses. We report the case of an HCMV-transmitter mother observed with dissociation between humoral and cell-mediated immune responses. The patient had immunoglobulin (Ig) G and M positivity at 11 weeks of gestation and showed fetal hyperechoic bowel and minimal ascites at 21 weeks of gestation. At 25 weeks of gestation, the polymerase chain reaction result for HCMV using amniotic fluid was positive. The numbers of spots in the enzyme-linked immunosorbent spot (ELISPOT) assay at 25, 36, and 39 weeks of gestation were three, five, and six spots/2 × 105 peripheral blood mononuclear cells, respectively. Furthermore, IgG avidity indexes (AIs) at 21, 25, 36, and 39 weeks of gestation were 37.6, 49.7, 72.5, and 74.3, respectively. At 40+1 weeks of gestation, the patient delivered a symptomatic infected newborn with a weight of 2,384 g (-2.6 SD) and a head circumference of 30 cm (-2.6 SD). The neonate had a petechial rash and bilateral hearing loss although did not show liver dysfunction or thrombocytopenia. Cranial magnetic resonance imaging revealed mild ventriculomegaly, left lateral/parietal polymicrogyria, and a punctate white matter lesion. This case showed that IgG AI increased with increasing gestational age, whereas the numbers of spots in the ELISPOT assay had no change. The dissociation between humoral and cell-mediated immune responses may be characteristic of the immune response of a transmitter mother.

Vestibular Follow-up Program for Congenital Cytomegalovirus Based on 6 Years of Longitudinal Data Collection

OBJECTIVES

Congenital cytomegalovirus (cCMV), the leading nongenetic cause of pediatric sensorineural hearing loss, can also affect vestibular function. Literature findings suggest clinical presentation of vestibular loss in cCMV to be as variable as the hearing loss. Still, probably due to the considerable additional burden it entails for both patients and diagnostic centers, longitudinal vestibular follow-up in cCMV is not well-established in clinical practice. Therefore, this study aims to propose an evidence-based vestibular follow-up program with proper balance between its feasibility and sensitivity.

DESIGN

In this longitudinal cohort study, 185 cCMV-patients (mean age 3.2 years, SD 1.6 years, range 0.5-6.7 years) were included. Vestibular follow-up data were obtained through lateral video head impulse test (vHIT) and cervical vestibular evoked myogenic potential (cVEMP) evaluations around the ages of 6 months, 1 year, and 2 years. Around 3 and 4.5 years of age, data from vertical vHIT and ocular vestibular evoked myogenic potentials (oVEMP) were also collected.

RESULTS

At birth, 55.1% (102/185) of patients were asymptomatic and 44.9% (83/185) were symptomatic. The mean duration of follow-up for all patients was 20.8 (SD 16.3) months (mean number of follow-up assessments: 3.2, SD 1.5). Vestibular loss occurred at some point during follow-up in 16.8% (31/185) of all patients. Six percent (10/164) of patients with normal vestibular function at first assessment developed delayed-onset vestibular loss; 80.0% (8/10) of these within the first 2 years of life. Vestibular deterioration was reported both in patients who had been treated with postnatal antiviral therapy and untreated patients. At final evaluation, both the semicircular and the otolith system were impaired in the majority of vestibular-impaired ears (29/36, 80.6%). Dysfunctions limited to the semicircular system or the otolith system were reported in 4 (4/36, 11.1%) and 3 (3/36, 8.3%) ears, respectively. The occurrence of vestibular loss was highest in patients with first trimester seroconversion (16/59, 27.1%) or with an unknown timing of seroconversion (13/71, 18.3%), patients with sensorineural hearing loss (16/31, 51.6%), and patients with periventricular cysts on magnetic resonance imaging (MRI) (7/11, 63.6%).

CONCLUSIONS

Longitudinal vestibular follow-up, most intensively during the first 2 years of life, is recommended in cCMV-patients with vestibular risk factors (first trimester or unknown timing of seroconversion; sensorineural hearing loss; periventricular cysts on MRI). If those risk factors can be ruled out, a single evaluation early in life (around 6 months of age) might be sufficient. Both semicircular and otolith system evaluation should be part of the follow-up program, as partial losses were reported.

Cytomegalovirus infection during pregnancy

Cytomegalovirus (CMV) infection during pregnancy is a global silent problem. Additionally, it is the leading cause of congenital infections, non-genetic sensorineural hearing loss, and neurodevelopmental delays in infants. However, this has barely been recognized globally. This condition lacks adequate attention, which is further emphasized by the lack of awareness among healthcare workers and the general population. The impact of CMV infection is often overlooked because of the asymptomatic nature of its presentation in infected pregnant women and newborns, difficulty in diagnosis, and the perception that infants born to women with pre-existing antibodies against CMV have normal neonatal outcomes. This article highlights the latest information on the epidemiology, transmission, clinical manifestations, and development of CMV infection and its management. We reviewed the pathophysiology and clinical manifestations of CMV infection in pregnant women, diagnostic methods, including screening and prognostic markers, and updates in treatment modalities. Current advancements in research on vaccination and hyperimmunoglobulins with worldwide treatment protocols are highlighted.