Sequelae of Congenital Cytomegalovirus Following Maternal Primary Infections Are Limited to Those Acquired in the First Trimester of Pregnancy

Ultrasound features of congenital cytomegalovirus infection in the first trimester: A case report

BACKGROUND

Congenital cytomegalovirus (CMV) infection represents a significant public health concern as the most prevalent viral infection in newborns, potentially leading to severe neurological and developmental complications. The majority of cases are asymptomatic and remain undetected during pregnancy due to the absence of effective screening methods.

CASE SUMMARY

A 27-year-old primigravida presented for early pregnancy ultrasound, which revealed an atypical finding: A normal anechoic thalamus appearing hyperechoic on the mid-sagittal view of the fetal head. Subsequent ultrasound examinations during mid and late gestation demonstrated classic intracranial features suggestive of congenital CMV infection. Chromosomal karyotyping and microarray analysis of the fetus yielded no significant abnormalities. Following comprehensive prenatal counseling regarding potential adverse fetal outcomes, the patient elected to continue her pregnancy. She ultimately underwent cesarean delivery at 42 weeks gestation at another facility, resulting in the birth of a female neonate. At five months of age, the infant presented with epilepsy and significant growth and developmental delays.

CONCLUSION

Congenital CMV infection occurs during the first trimester may manifest as hyperechoic thalamus which can be revealed by ultrasound in the mid-saggital view of the fetal head. Future research should investigate the correlation between echogenic thalamus and developmental outcomes, as well as explore early screening techniques for suspected congenital CMV infection cases.

Congenital Cytomegalovirus Infection: Update on Screening, Diagnosis and Treatment: Scientific Impact Paper No. 56

Cytomegalovirus (CMV) is the most common cause of viral infection in newborn babies, and affects 1 in 200 of all live born infants in high-income countries; and 1 in 71 in low- and middle-income countries. It is a major cause of hearing loss and brain damage. Women may get CMV infection for the first time during pregnancy (primary infection) or may experience 'non-primary' infection, either by reactivation of previous CMV infection or by a new infection with a different strain of the virus. The most common source of infection to pregnant women is the saliva and urine of young children. Therefore, all pregnant women, especially those in regular contact with young children, should be informed about hygiene-based measures to reduce the risks, e.g. handwashing. The UK National Screening Committee recommends against universal antenatal or newborn screening for CMV. Testing for CMV is usually offered only to women who develop symptoms of influenza, glandular fever or hepatitis (liver inflammation) during pregnancy, or for those whom a routine ultrasound scan detects fetal anomalies that suggests possible CMV infection. The risk of harm to the fetus is greatest following primary CMV infection of the woman in early pregnancy, and appears to be very low following infection after 12 weeks of pregnancy. Babies with CMV infection at birth may have jaundice, a rash, enlarged liver or spleen, a small brain, or be small for their gestational age. Around 1 in 8 babies born with CMV infection will have clinically detectable signs at birth. The rest will not have any features detectable by clinical examination alone. Therefore, all infants with CMV infection at birth should be followed up at a minimum of up to 2 years of age or later, depending upon the disease status, to check hearing and brain development. Following primary CMV infection in the first 12 weeks of pregnancy, if the woman starts taking the antiviral medicine valaciclovir (valacyclovir) it reduces the risk of the baby becoming infected. Where CMV infection of the fetus in the womb has been confirmed (by amniocentesis, for example), regular ultrasound scans should be offered every 2-3 weeks until birth. Detailed assessment of the fetal brain is an essential part of these scans. Where maternal CMV infection occurs, but fetal infection is not confirmed, repeated ultrasound scans of the fetus should be offered every 2-3 weeks until birth. In infected fetuses, as well as ultrasound scans, an MRI scan of the brain should be offered at 28-32 weeks of gestation (and sometimes repeated 3-4 weeks later) to assess for any signs of harm to the fetal brain. All babies born to women with confirmed or suspected CMV infection should be tested for CMV with a urine or saliva sample within the first 21 days of life. In newborns with symptomatic CMV infection at birth, treatment with antiviral medicine (valganciclovir or ganciclovir) can reduce hearing loss in 5 out of 6 babies, and improve long-term brain development outcomes in some. There is no licensed vaccine for CMV.

Risk factors associated with late-onset hearing loss in children with congenital cytomegalovirus: a systematic review

PURPOSE

To search for existing evidence of prognostic factors related to the development of late-onset hearing loss (LOHL) in infants with congenital cytomegalovirus (cCMV).

METHODS

A PRISMA systematic review was performed, with the PubMed, Embase, and Web of Science databases searched from inception through to December 2023; after the application of inclusion and exclusion criteria a total of 9 papers were included in this review. PROSPERO registration number CRD42024492244.

RESULTS

9 studies encompassing a total of 292 children with late-onset hearing loss were included. A total of 12 risk factors were identified in the literature, with 6 found to be statistically significant. Late-onset hearing loss was more frequently reported in children with symptomatic than asymptomatic cCMV. Moreover, in asymptomatic cCMV cases, elevated DNAemia and salivary viral load were associated with late-onset hearing loss. Additionally, first-trimester seroconversion was identified as a risk factor for late- onset hearing loss. Further, gestational age < 37 weeks and low birth weight were found to correlate with late-onset hearing loss. Remarkably, only one study documented a relationship between late-onset hearing loss and ultrasonographic abnormalities.

CONCLUSIONS

Although six statistically significant risk factors have been identified, the available evidence is limited and inconsistent, preventing the establishment of reliable neonatal and maternal parameters to predict the development of LOHL in patients with CMV. There are few studies addressing this topic, and those available exhibit a low level of evidence and heterogeneous designs. More studies should be done.

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.

Audiological and Vestibular Follow-Up for Children with Congenital Cytomegalovirus Infection: From Current Limitations to Future Directions

Currently, the guidelines for audiological and vestibular follow-up in children with congenital cytomegalovirus (CMV) are not well-defined. The general recommendation is to evaluate hearing in all children with congenital CMV at the same intervals: once every 3-6 months up to 1 year of age, once every 6 months from 1 to 3 years of age, and once a year from 3 to 6 years of age. Additionally, there are no universally accepted protocols for the vestibular follow-up of children with congenital CMV, although video head impulse test (v-HIT) and cervical vestibular-evoked myogenic potentials (cVEMPs) are sometimes used. This narrative review critically evaluates existing audiological and vestibular follow-up approaches for children with congenital CMV, highlighting the need for personalized protocols. Tailoring follow-up schedules with different timing and methods based on risk factors, such as the trimester of maternal infection, CMV PCR results in amniotic fluid, and valganciclovir use, would indeed allow for more precise evaluations, timely interventions, and optimized resource allocation. This strategy would also alleviate the logistical and emotional burdens on families by ensuring that high-risk children receive more frequent and appropriate assessments and early interventions, while lower-risk children avoid unnecessary testing.

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.

T-Cell Immune Responses in Newborns and Long-Term Sequelae in Congenital Cytomegalovirus Infection (CYTRIC Study)

OBJECTIVE

The objective of this study was to assess the role of T-lymphocyte immune responses in newborns with congenital cytomegalovirus (CMV) infection (cCMV) and their potential association with the development of long-term sequelae.

STUDY DESIGN

A multicenter, prospective study from 2017 to 2022 was conducted across 8 hospitals in Spain. Blood samples were collected within the first month of life from neonates diagnosed with cCMV. Intracellular cytokine staining was employed to evaluate the presence of CMV-specific interferon-gamma (IFN-γ)-producing CD8+ and CD4+ T lymphocytes (CMV-IFN-γ-CD8+/CD4+) using flow cytometry. The development of sequelae, including hearing loss and neurologic impairment, was assessed during follow-up.

RESULTS

In total, 64 newborns were included; 42 infants (65.6%) had symptomatic cCMV. The median age at the last follow-up visit was 25.3 months (IQR 20.1-34.4). Eighteen infants had long-term sequelae (28.1%), predominantly hearing loss (20.3%) and neurologic disorders (15.6%). No relationship was observed between total count or percentage of CMV-specific IFN-γ-CD8+ or CD4+ lymphocytes and long-term sequelae. Multivariable analysis demonstrated an association between lower total lymphocyte count and long-term sequelae (aOR 0.549, 95% CI: 0.323-0.833), which requires further study.

CONCLUSIONS

CMV-specific IFN-γ-CD4+ and CD8+ T-lymphocyte responses in neonates with cCMV were not predictive of long-term sequelae.

Burden of Congenital CMV Infection: A Narrative Review and Implications for Public Health Interventions

Cytomegalovirus causes the most common congenital infection worldwide. With most infants asymptomatic at birth, the few affected may present with variable clinical scenarios, from isolated hearing loss to severe neurologic impairment. Public health interventions include all actions at the health system, community, and individual levels that aim at reducing the burden of congenital Cytomegalovirus. This review examines the literature on maternal and neonatal screening programs in light of current evidence for treatment and the development of vaccines against Cytomegalovirus. Potential biases and benefits of these interventions are outlined, with the objective of increasing awareness about the problem and providing readers with data and critical tools to participate in this ongoing debate.

Cytomegalovirus-Specific Hyperimmune Immunoglobulin Administration for Secondary Prevention after First-Trimester Maternal Primary Infection: A 13-Year Single-Center Cohort Study

Primary cytomegalovirus infection during pregnancy has a high risk of vertical transmission, with severe fetal sequelae mainly associated with first-trimester infections. We conducted a retrospective analysis of 200 IU/kg cytomegalovirus-specific hyperimmune globulin (HIG), used in first-trimester maternal primary infections for congenital infection prevention. The primary outcome was vertical transmission, defined as neonatal viruria or positive amniocentesis if pregnancy was discontinued. HIG, initially administered monthly and since 2019 biweekly, was discontinued in negative amniocentesis cases. Women declining amniocentesis and positive amniocentesis cases with normal sonography were offered monthly HIG until delivery as a treatment strategy. The total transmission rate was 29.9% (32/107; 10 pregnancy terminations with positive amniocentesis, 18 completed pregnancies with positive amniocentesis and 4 declining amniocentesis). Maternal viremia was the only factor associated with fetal transmission (OR 4.62, 95% CI 1.55-13.74). The transmission rate was not significantly different whether HIG was started during the first or second trimester (28.2% vs. 33.3%; p = 0.58), or between monthly and biweekly subgroups (25.7% vs. 37.8%, p = 0.193). Pre-treatment maternal viremia could inform decisions as a predictor of congenital infection.

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.

Valganciclovir in Infants with Hearing Loss and Clinically Inapparent Congenital Cytomegalovirus Infection: A Nonrandomized Controlled Trial

OBJECTIVE

To assess the efficacy of valganciclovir in infants with hearing loss and clinically inapparent congenital cytomegalovirus infection (cCMV), as there is no consensus on treatment of this group.

STUDY DESIGN

A nationwide, nonrandomized controlled trial, comparing 6 weeks of oral valganciclovir to no treatment in infants with cCMV, recruited after newborn hearing screening resulted in referral to an audiologist. The choice whether to treat was left to parents of subjects. Eligible subjects were full term infants aged <13 weeks with sensorineural hearing loss and diagnosed with cCMV through dried blood spot testing. The primary outcome, measured by linear and ordinal logistic regression, was change in best-ear hearing from baseline to follow-up at 18-22 months of age.

RESULTS

Thirty-seven participants were included in the final analysis, of whom 25 were in the treatment group and 12 in the control group. The majority of subjects in both groups had neuroimaging abnormalities, which were mostly mild. Hearing deterioration was more likely in the control group compared with the treatment group (common OR 0.10, 95% CI 0.02-0.45, P = .003). Mean best-ear hearing deteriorated by 13.7 dB in the control group, compared with improvement of 3.3 dB in the treatment group (difference 17 dB, 95% CI 2.6 - 31.4, P = .02).

CONCLUSIONS

We investigated treatment in children with hearing loss and clinically inapparent cCMV. Although our study was nonrandomized, it is the first prospective and controlled trial in this population. Valganciclovir-treated children with hearing loss and inapparent cCMV had less hearing deterioration at 18 through 22 months of age than control subjects.

EUDRACT REGISTRY NUMBER

2013-003068-30.

Human trophoblast stem cells restrict human cytomegalovirus replication

Placental infection plays a central role in the pathogenesis of congenital human cytomegalovirus (HCMV) infections and is a cause of fetal growth restriction and pregnancy loss. HCMV can replicate in some trophoblast cell types, but it remains unclear how the virus evades antiviral immunity in the placenta and how infection compromises placental development and function. Human trophoblast stem cells (TSCs) can be differentiated into extravillous trophoblasts (EVTs), syncytiotrophoblasts (STBs), and organoids, and this study assessed the utility of TSCs as a model of HCMV infection in the first-trimester placenta. HCMV was found to non-productively infect TSCs, EVTs, and STBs. Immunofluorescence assays and flow cytometry experiments further revealed that infected TSCs frequently only express immediate early viral gene products. Similarly, RNA sequencing found that viral gene expression in TSCs does not follow the kinetic patterns observed during lytic infection in fibroblasts. Canonical antiviral responses were largely not observed in HCMV-infected TSCs and TSC-derived trophoblasts. Rather, infection dysregulated factors involved in cell identity, differentiation, and Wingless/Integrated signaling. Thus, while HCMV does not replicate in TSCs, infection may perturb trophoblast differentiation in ways that could interfere with placental function.

IMPORTANCE

Placental infection plays a central role in human cytomegalovirus (HCMV) pathogenesis during pregnancy, but the species specificity of HCMV and the limited availability and lifespan of primary trophoblasts have been persistent barriers to understanding how infection impacts this vital organ. Human trophoblast stem cells (TSCs) represent a new approach to modeling viral infection early in placental development. This study reveals that TSCs, like other stem cell types, restrict HCMV replication. However, infection perturbs the expression of genes involved in differentiation and cell fate determination, pointing to a mechanism by which HCMV could cause placental injury.

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.

Predictors of the Outcome at 2 Years in Neonates With Congenital Cytomegalovirus Infection

BACKGROUND

Approximately 20% of neonates with congenital cytomegalovirus (cCMV) develop long-term sequelae. The ability to accurately predict long-term outcomes as early as the neonatal period would help to provide for appropriate parental counseling and treatment indications. With this study, we aimed to identify neonatal predictive markers of cCMV long-term outcomes.

METHODS

As this study's subjects, we chose neonates diagnosed with cCMV in 13 hospitals throughout France recruited from 2013 to 2017 and evaluated for at least 2 years with thorough clinical, audiology, and imaging evaluations and psychomotor development tests.

RESULTS

A total of 253 neonates were included, and 3 were later excluded because of the identification of a genetic disorder. A total of 227 were followed up for 2 years: 187/227 (82%) and 34/227 (15%) were infected after a maternal primary or nonprimary infection, respectively, 91/227 (40%) were symptomatic at birth, and 44/227 (19%) had cCMV sequelae. Maternal primary infection in the first trimester was the strongest prognosis factor (odds ratio = 38.34 [95% confidence interval, 5.02-293], P < .001). A predictive model of no risk of sequelae at 2 years of age according to normal hearing loss at birth, normal cerebral ultrasound, and normal platelet count had 98% specificity, 69% sensitivity, and 0.89 area under the curve (95% confidence interval, 0.83-0.96).

CONCLUSIONS

In the studied population, children with normal hearing at birth, normal platelet count at birth, and a normal cranial ultrasound had no risk of neurologic sequelae and a low risk of delayed unilateral sensorineural hearing loss. The use of this model based on readily available neonatal markers should help clinicians establish a personalized care pathway for each cCMV neonate.

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.

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.

Risk Factors for Natural Hearing Evolution in Newborns With Congenital Cytomegalovirus Infection

Importance

Congenital cytomegalovirus (cCMV) is the major cause of congenital nonhereditary sensorineural hearing loss in children. Currently, criteria to identify infants at increased risk for unfavorable hearing outcome are lacking.

Objective

To identify risk factors associated with cCMV-related hearing improvement, hearing deterioration, and late-onset hearing loss.

Design, Setting, and Participants

This multicenter cohort study included patients from 6 secondary and tertiary hospitals enrolled in the Flemish CMV registry (Belgium). Newborns with untreated cCMV infection with at least 4-year audiological follow-up were included. Patients who presented with other possible causes of sensorineural hearing loss were excluded. Data were collected for 15 years (January 1, 2007, to February 7, 2022) and analyzed from September 26, 2022, to January 16, 2023.

Main Outcomes and Measures

Primary outcome was hearing evolution (per-ear analysis; described as stable hearing, improvement, or deterioration). The association of gestational characteristics, clinical findings, timing of seroconversion, viral load, and hearing status at birth with hearing evolution was investigated using effect sizes (Cramer V, odds ratio [OR], or Hedges g).

Results

Of the 387 children, 205 of 385 with nonmissing data were male (53.2%), 113 (29.2%) had a symptomatic infection, and 274 (70.8%) had an asymptomatic infection. Every child was 4 years or older at final hearing evaluation. A total of 701 of 774 ears (90%) showed stable hearing (normal hearing or stable hearing loss since birth) over time. Late-onset hearing loss (normal hearing at birth followed by hearing loss) was present in 43 of 683 ears (6.3%). Among children with hearing loss present at birth, 24 of 34 ears (70.6%) had hearing deterioration, and 6 of 91 ears (6.6%) had hearing improvement. Prematurity was associated with a higher chance of hearing improvement (OR, 12.80; 95% CI, 2.03-80.68). Late-onset hearing loss was more prevalent in a first trimester infection (OR, 10.10; 95% CI, 2.90-34.48). None of the 104 ears of children with a third trimester seroconversion developed late-onset hearing loss.

Conclusions and Relevance

Findings of this cohort study support that ongoing audiological follow-up for untreated children with congenital hearing loss is important, as the majority of patients had hearing deterioration. The timing of seroconversion was associated with the risk of developing late-onset hearing loss. These insights can aid in parental counseling, patient stratification, and follow-up. Future research should focus on the effect of treatment, the influence of determined risk factors, and the study of eventual new risk factors in patients at high risk to develop hearing loss.

Human Trophoblast Stem Cells Restrict Human Cytomegalovirus Replication

Placental infection plays a central role in the pathogenesis of congenital human cytomegalovirus (HCMV) infections and is a cause of fetal growth restriction and pregnancy loss. HCMV can replicate in some trophoblast cell types, but it remains unclear how the virus evades antiviral immunity in the placenta and how infection compromises placental development and function. Human trophoblast stem cells (TSCs) can be differentiated into extravillous trophoblasts (EVTs), syncytiotrophoblasts (STBs), and organoids, and this study assessed the utility of TSCs as a model of HCMV infection in the first trimester placenta. HCMV was found to non-productively infect TSCs, EVTs, and STBs. Immunofluorescence assays and flow cytometry experiments further revealed that infected TSCs frequently only express immediate early viral gene products. Similarly, RNA-sequencing found that viral gene expression in TSCs does not follow the kinetic patterns observed during lytic infection in fibroblasts. Canonical antiviral responses were largely not observed in HCMV-infected TSCs and TSC-derived trophoblasts. Rather, infection dysregulated factors involved in cell identity, differentiation, and WNT signaling. Thus, while HCMV does not replicate in TSCs, infection may perturb trophoblast differentiation in ways that could interfere with placental function.

Importance

Placental infection plays a central role in HCMV pathogenesis during pregnancy, but the species-specificity of HCMV and the limited availability and lifespan of primary trophoblasts have been persistent barriers to understanding how infection impacts this vital organ. Human TSCs represent a new approach to modeling viral infection early in placental development. This study reveals that TSCs, like other stem cell types, restrict HCMV replication. However, infection perturbs the expression of genes involved in differentiation and cell fate determination, pointing to a mechanism by which HCMV could cause placental injury.

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.

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.

Burden of sequelae and healthcare resource utilization in the first year of life in infants born with congenital cytomegalovirus (cCMV) infection in Germany: A retrospective statutory health insurance claims database analysis

BACKGROUND

Congenital cytomegalovirus (cCMV) infection can have a broad range of manifestations. This study aimed to assess cCMV-associated sequelae and healthcare resource utilization (HCRU) in infants during the first year of life in Germany.

METHODS

A retrospective, controlled cohort study using German claims data from the Institute for Applied Health Research Berlin (InGef) database was conducted. cCMV-associated sequelae and HCRU during the first year of life were assessed by matching (1:60) infants with at least one inpatient/outpatient cCMV diagnosis (ICD-10-GM: P35.1) ≤90 days after birth (cCMV90 cohort) and infants with at least one inpatient cCMV diagnosis plus specific sequelae ≤21 days after birth (cCMV21-S) to infants without cCMV or CMV (ICD-10-GM: B25) diagnosis (control group), respectively. Outcomes were analyzed during the first 365 days of life.

RESULTS

Between 2014-2018, we identified 54 newborns for cCMV90 and 24 newborns for cCMV21-S cohort. Compared to the 3,240 and 1,440 controls, respectively, more cCMV90 infants (83.3% vs. 41.9%, p<0.01) presented with at least one sequela during the first year of life, including intrauterine growth retardation (42.6% vs. 5.3%, p<0.01), sensorineural hearing loss (SNHL) to deafness (38.9% vs. 2.2%, p<0.01), and motor development disorders (33.3% vs. 10.9%, p<0.01). Further, 13.0% of cCMV90 infants (vs. 2.3%, p<0.01) suffered from visual impairment. In cCMV21-S cohort, intrauterine growth retardation (79.2% vs. 6.0%, p<0.01), prematurity (54.2% vs. 7.3%, p<0.01), and motor development disorders (50.0% vs. 11.0%, p<0.01) were the most frequent sequelae. Infants in the cCMV90 and cCMV21-S cohort had, on average, 7.3 times and 9.5 times more hospitalizations and 2.0 times and 2.1 times more outpatient physician visits than their respective controls (p<0.01). Hospitalized infants with cCMV stayed, on average, significantly longer in hospital compared to their controls (cCMV90 cohort: 30.3 days vs. 9.0 days, p<0.01; cCMV21-S cohort: 46.5 days vs. 9.3 days, p<0.01).

CONCLUSIONS

cCMV-infection shows a considerable disease and healthcare burden during the first year of life. More than 80% of the identified newborns with cCMV suffered from at least one associated sequela during the first year of life, including long-term sequelae such as SNHL (40%) and visual impairment (13%). Additional steps for prevention of cCMV infection and associated sequelae as well as a comprehensive monitoring of disease burden are needed.

Treatment with valacyclovir during pregnancy for prevention of congenital cytomegalovirus infection: a real-life multicenter Italian observational study

BACKGROUND

Valacyclovir is the only treatment demonstrated to be effective for the prevention of vertical transmission of cytomegalovirus within a clinical randomized, placebo-controlled trial and has been reimbursed by the Italian National Health System since December 2020.

OBJECTIVE

This study reported the results of a real-life Italian multicenter observational study on cytomegalovirus infection in pregnancy evaluating the effect of the introduction of valacyclovir in the clinical practice for the prevention of vertical transmission of cytomegalovirus.

STUDY DESIGN

The outcomes of women who received valacyclovir treatment and their fetuses or newborns were compared with those of a retrospective cohort observed between 2010 and 2020 who did not receive the antiviral treatment. The inclusion criterion was the diagnosis of cytomegalovirus primary infection occurring in the periconceptional period or up to 24 weeks of gestation. The primary outcome was the transmission by the time of amniocentesis. The secondary outcomes were termination of pregnancy, transmission at birth, symptomatic infection at birth, and a composite outcome (termination of pregnancy or transmission at birth).

RESULTS

A total of 447 pregnant women from 10 centers were enrolled, 205 women treated with valacyclovir (called the valacyclovir group, including 1 twin pregnancy) and 242 women not treated with valacyclovir (called the no-valacyclovir group, including 2 twin pregnancies). Valacyclovir treatment was significantly associated with a reduction of the diagnosis of congenital cytomegalovirus infection by the time of amniocentesis (weighted odds ratio, 0.39; 90% confidence interval, 0.22-0.68; P=.005; relative reduction of 61%), termination of pregnancy (weighted odds ratio, 0.36; 90% confidence interval, 0.17-0.75; P=.0021; relative reduction of 64%), symptomatic congenital cytomegalovirus infection at birth (weighted odds ratio, 0.17; 90% confidence interval, 0.06-0.49; P=.006; relative reduction of 83%). The treatment had no significant effect on the rate of diagnosis of congenital cytomegalovirus infection at birth (weighted odds ratio, 0.85; 90% confidence interval, 0.57-1.26; P=.500), but the composite outcome (termination of pregnancy or diagnosis of congenital cytomegalovirus infection at birth) occurred more frequently in the no-valacyclovir group (weighted odds ratio, 0.62; 90% confidence interval, 0.44-0.88; P=.024). Of note, the only symptomatic newborns with congenital cytomegalovirus infection in the valacyclovir group (n=3) were among those with positive amniocentesis. Moreover, 19 women (9.3%) reported an adverse reaction to valacyclovir treatment, classified as mild in 17 cases and moderate in 2 cases. Lastly, 4 women (1.9%) presented renal toxicity with a slight increase in creatinine level, which was reversible after treatment suspension.

CONCLUSION

Our real-life data confirm that valacyclovir significantly reduces the rate of congenital cytomegalovirus diagnosis at the time of amniocentesis with a good tolerability profile and show that the treatment is associated with a reduction of termination of pregnancy and symptomatic congenital cytomegalovirus infection at birth.

Cost-effectiveness of screening and valacyclovir-based treatment strategies for first-trimester cytomegalovirus primary infection in pregnant women in France

OBJECTIVE

To assess the effectiveness, cost and cost-effectiveness of four screening strategies for first-trimester (T1) cytomegalovirus (CMV) primary infection (PI) in pregnant women in France.

METHODS

In a simulated pregnant population of 800 000 (approximate number of pregnancies each year in France), using costs based on the year 2022, we compared four CMV maternal screening strategies: Strategy S1, no systematic screening (current public health recommendations in France); Strategy S2, screening of 25-50% of the pregnant population (current screening practice in France); Strategy S3, universal screening (current medical recommendations in France); Strategy S4, universal screening (as in Strategy S3) in conjunction with valacyclovir in case of T1 PI. Outcomes were total cost, effectiveness (number of congenital infections, number of diagnosed infections) and incremental cost-effectiveness ratio (ICER). Two ICERs were calculated, comparing Strategies S1, S2 and S3 in terms of euros (€) per additional diagnosis, and comparing Strategies S1 and S4 in € per avoided congenital infection.

RESULTS

Compared with Strategy S1, Strategy S3 enabled diagnosis of 536 more infected fetuses and Strategy S4 prevented 375 congenital infections. Strategy S1 was the least expensive strategy (€98.3m total lifetime cost), followed by Strategy S4 (€98.6m), Strategy S2 (€106.0m) and Strategy S3 (€118.9m). In the first analysis, Strategy S2 was dominated and Strategy S3 led to an additional €38 552 per additional in-utero diagnosis, compared with Strategy S1. In the second analysis, Strategy S4 led to an additional €893 per avoided congenital infection compared with Strategy S1, and was cost-saving compared with Strategy S2.

CONCLUSIONS

In France, current screening practice for CMV PI during pregnancy is no longer acceptable in terms of cost-effectiveness because this strategy was dominated by universal screening. Moreover, universal screening in conjunction with valacyclovir treatment would be cost-effective compared with current recommendations and is cost-saving compared with current practice. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

CMV-induced Hearing Loss

Congenital cytomegalovirus (cCMV) infection is the most common fetal viral infection and contributes to about 25% of childhood hearing loss by the age of 4 years. It is the leading nongenetic cause of sensorineural hearing loss (SNHL). Infants born to seroimmune mothers are not completely protected from SNHL, although the severity of their hearing loss may be milder than that seen in those whose mothers had a primary infection. Both direct cytopathic effects and localized inflammatory responses contribute to the pathogenesis of cytomegalovirus (CMV)-induced hearing loss. Hearing loss may be delayed onset, progressive or fluctuating in nature, and therefore, a significant proportion will be missed by universal newborn hearing screening (NHS) and warrants close monitoring of hearing function at least until 5-6 years of age. A multidisciplinary approach is required for the management of hearing loss. These children may need assistive hearing devices or cochlear implantation depending on the severity of their hearing loss. In addition, early intervention services such as speech or occupational therapy could help better communication, language, and social skill outcomes. Preventive measures to decrease intrauterine CMV transmission that have been evaluated include personal protective measures, passive immunoprophylaxis and valacyclovir treatment during pregnancy in mothers with primary CMV infection. Several vaccine candidates are currently in testing and one candidate vaccine in phase 3 trials. Until a CMV vaccine becomes available, behavioral and educational interventions may be the most effective strategy to prevent maternal CMV infection.

Revised Protocol for Secondary Prevention of Congenital Cytomegalovirus Infection With Valaciclovir Following Infection in Early Pregnancy

BACKGROUND

A previous randomized placebo-controlled study found valaciclovir to be effective in reducing the rate of vertical cytomegalovirus transmission from mother to fetus. The better results in women infected in the first trimester compared to the periconception period were attributed to the timing of treatment. The aim of the present study was to evaluate valaciclovir efficacy in this setting using a revised protocol.

METHODS

All pregnant women treated with valaciclovir in 2020-2022 who met the same criteria as in the original study were identified retrospectively from the database of the same medical center. Treatment, however, was initiated earlier: up to 9 weeks or 8 weeks from the presumed time of infection in women infected in the periconception period or the first trimester, respectively. The primary endpoint was rate of vertical cytomegalovirus transmission. Results were compared with the placebo arm in the previous study.

RESULTS

Among 178 women who completed valaciclovir treatment, amniocentesis was positive for cytomegalovirus in 14 women (7.9%), significantly (P < .001) lower compared with 14 of 47 (30%) in the placebo arm in the previous study. The proportion of positive amniocentesis in the valaciclovir was significantly lower than the placebo arm both among women infected in the first trimester (14/119 vs 11/23; odds ratio [OR] = 0.15; 95% confidence interval [CI]: .05-.45, P < .001), as well as among those infected in the periconception period (0/59 vs 3/24, OR = 0; 95% CI 0-.97, P = .02).

CONCLUSIONS

This study provides further evidence of the efficacy of valaciclovir in preventing vertical transmission of cytomegalovirus after primary maternal infection. Efficacy is improved with earlier treatment.

Universal screening programme for cytomegalovirus infection in the first trimester of pregnancy: study protocol for an observational multicentre study in the area of Barcelona (CITEMB study)

INTRODUCTION

Congenital cytomegalovirus (cCMV) is the leading cause of non-genetic sensorineural hearing loss and one of the main causes of neurological disability. Despite this, no universal screening programme for cCMV has been implemented in Spain. A recent study has shown that early treatment with valaciclovir, initiated in the first trimester and before the onset of signs in the fetus, reduces the risk of fetal infection. This finding favours the implementation of a universal screening programme for cCMV.The aim of this study is to evaluate the performance of a universal screening programme for cCMV during the first trimester of pregnancy in a primary care setting.

METHODS AND ANALYSIS

This is an observational multicentre cohort study. The study will be conducted in four primary care settings from the Northern Metropolitan Barcelona area and three related hospitals and will last 3 years and will consist of a recruitment period of 18 months.In their first pregnancy visit, pregnant women will be offered to add a CMV serology test to the first trimester screening tests. Pregnant women with primary infection will be referred to the reference hospital, where they will continue treatment and follow-up according to the clinical protocol of the referral hospital, which includes treatment with valacyclovir. A CMV-PCR will be performed at birth on newborns of mothers with primary infection, and those who are infected will undergo neonatal follow-up for at least 12 months of life.For the analysis, the acceptance rate, the prevalence of primary CMV infections and the CMV seroprevalence in the first trimester of pregnancy will be studied.

ETHICS AND DISSEMINATION

Ethical approval was obtained from the University Institute Foundation for Primary Health Care Research Jordi Gol i Gurina Ethics Committee 22/097-P dated 27 April 2022.

Integrated immune monitoring of HCMV infection in pregnant women with complications and its association with adverse pregnancy outcomes

Human Cytomegalovirus (HCMV) infection is associated with bad obstetric history (BOH) and adverse pregnancy outcomes (APO). Here, we characterized antiviral humoral profiles, systemic and virus specific cellular immune responses concurrently in pregnant women (n = 67) with complications including BOH and associated these signatures with pregnancy outcomes. Infection status was determined using nested blood PCR, seropositivity and IgG avidity by ELISA. Systemic and HCMV specific (pp65) cellular immune responses were evaluated by flow cytometry. Seropositivity was determined for other TORCH pathogens (n = 33) on samples with recorded pregnancy outcomes. This approach was more sensitive in detecting HCMV infection. Blood PCR positive participants, irrespective of their IgG avidity status, had higher cytotoxic potential in circulating CD8+ T cells (p < 0.05) suggesting that infection associated cellular dysfunction was uncoupled with avidity maturation of antiviral humoral responses. Also, impaired anamnestic degranulation of HCMV-pp65-specific T cells compared to HCMV blood PCR negative participants (p < 0.05) was observed. APO correlated with HCMV blood PCR positivity but not serostatus (p = 0.0039). Most HCMV IgM positive participants (5/6) were HCMV blood PCR positive with APO. None were found to be IgM positive for other TORCH pathogens. Multiple TORCH seropositivity however was significantly enriched in the APO group (p = 0.024). Generation of HCMV specific high avidity IgG antibodies had no bearing on APO (p = 0.9999). Our study highlights the utility of an integrated screening approach for antenatal HCMV infection in the context of BOH, where infection is associated with systemic and virus specific cellular immune dysfunction as well as APO.

Neurodevelopmental outcome in children with congenital cytomegalovirus infection: A prospective multicenter cohort study

BACKGROUND

Congenital cytomegalovirus infection (cCMV) is the most common congenital infection worldwide and is a major cause of neurodevelopmental impairment in children. At this point there are insufficient data on neurodevelopmental outcome of children with cCMV, both symptomatic and asymptomatic.

AIM

This study aimed to describe the neurodevelopmental outcome in a large prospective cohort of children with cCMV.

METHODS

All children with cCMV, included in the Flemish cCMV register, were eligible for this study. Data on neurodevelopmental outcome was available in 753 children. Data on neuromotor, cognitive, behavioral, audiological and ophthalmological outcome were analyzed.

RESULTS

Neurodevelopmental outcome was normal in 530/753 (70,4 %) at any age of last follow-up. Mild, moderate and severe neurodevelopmental impairment was found in 128/753 (16,9 %), 56/753 (7,4 %) and 39/753 (5,2 %), respectively. Adverse outcome is found both in the symptomatic and asymptomatic children (53,5 % versus 17,8 %). Autism spectrum disorder (ASD) was diagnosed more often than in the general population in Flanders (2,5 % versus 0,7 %). Speech and language impairment was found in 2 %, even in absence of hearing loss.

CONCLUSION

Both symptomatic and asymptomatic cCMV children are at risk of sequelae, with higher risk in case of first trimester infection. During follow-up of this population, special attention should be given to the audiological follow-up, the presence of hypotonia at young age, the possible higher risk of ASD and the risk of speech and language impairment even in absence of hearing loss. Our results emphasize the need for multidisciplinary neurodevelopmental follow-up of all cCMV infected children.

Brain cortical maturation assessed by magnetic resonance imaging in unaffected or mildly affected fetuses with cytomegalovirus infection

OBJECTIVES

To assess by magnetic resonance imaging (MRI) the cortical maturation pattern in fetuses with cytomegalovirus (CMV) infection with mild or no abnormalities on ultrasound (US) and MRI, and to establish possible differences compared with healthy controls.

METHODS

This was a retrospective case-control study of consecutive pregnancies with a CMV-infected fetus undergoing prenatal MRI as a complementary diagnostic tool in two centers, and a control group of singleton low-risk pregnancies without fetal structural abnormalities, with normal fetal growth and with healthy newborns. CMV infection was confirmed by extraction of CMV-DNA from fetal and neonatal samples. Only fetuses with mild (mildly affected) or no (unaffected) neuroimaging abnormalities on US and MRI were included. MRI measurements of fetal parieto-occipital sulcus, cingulate sulcus and calcarine sulcus depth, Sylvian fissure depth and Sylvian fissure angles were performed and cortical development grading of specific cortical areas and sulci were assessed by one operator who was blinded to CMV infection status. Data were compared between controls and fetuses with CMV infection, using linear regression and non-parametric trend analysis.

RESULTS

Twenty-four CMV-infected fetuses (seven unaffected and 17 mildly affected) and 24 healthy controls that underwent fetal MRI between 27 and 36 weeks' gestation were included. Compared with controls, CMV-infected fetuses showed significantly larger median lateral ventricular width (right side, 7.8 (interquartile range (IQR), 5.9-9.9) mm vs 3.9 (IQR, 2.6-5.3) mm; left side, 7.5 (IQR, 6.0-10.9) mm vs 4.2 (IQR, 3.2-5.3) mm), significantly decreased parieto-occipital sulcus depth (right side, 12.6 (IQR, 11.3-13.5) mm vs 15.9 (IQR, 13.5-17.3) mm; left side, 12.3 (IQR, 10.6-13.5) mm vs 16.0 (IQR, 13.3-17.5) mm) and calcarine sulcus depth (right side, 15.4 (IQR, 14.4-16.3) mm vs 17.5 (IQR, 16.1-18.7) mm; left side, 14.6 (IQR, 14.1-15.6) mm vs 16.7 (IQR, 15.6-18.9) mm) (P < 0.001 for all). Compared with controls, CMV-infected fetuses also had significantly smaller upper (right side, 42.8° (IQR, 35.8-45.8°) vs 48.9° (IQR, 38.4-64.7°); left side, 40.9° (IQR, 34.2-45.8°) vs 48.2° (IQR, 41.9-60.7°)) and lower (right side, 41.6° (IQR, 34.4-49.2°) vs 48.9° (IQR, 40.6-60.9°); left side, 42.2° (IQR, 38.8-46.9°) vs 48.9° (IQR, 39.5-57.5°)) Sylvian fissure angles (P < 0.05 for all). In addition, the mildly affected CMV-infected fetuses had a significantly lower cortical development grading in the temporal and parietal areas, and the parieto-occipital and calcarine sulci compared with healthy fetuses (P < 0.05). These differences persisted when adjusting for gestational age, ipsilateral atrium width, fetal gender and when considering small-for-gestational age as a confounding factor.

CONCLUSIONS

Unaffected and mildly affected CMV-infected fetuses showed delayed cortical maturation compared with healthy controls. These results suggest that congenital CMV infection, even in non-severely affected fetuses that are typically considered of good prognosis, could be associated with altered brain cortical structure. Further research is warranted to better elucidate the correlation of these findings with neurodevelopmental outcomes. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Efficiency of CMV serodiagnosis during pregnancy in daily laboratory routine

BACKGROUND

Maternal acute primary cytomegalovirus (CMV) infection during the first trimester may cause severe long-term sequelae in newborns. For risk assessment, serological screening is routinely performed in pregnant women based on IgM, IgG and avidity tests using whole-virus antigen. A recent study evaluated the diagnostic value of recombinant protein-based ELISAs as second-line tests in pregnancy CMV screening, including anti-p52 IgM and anti-gB IgG as markers defining the early and late phase of infection, respectively. In the present study, these recombinant ELISAs were used as first-line screening tests in daily laboratory routine and compared to lysate-based assays with respect to [i] the number of conclusive results obtained with the initial sample and [ii] the underlying workload.

METHODS

553 unselected routine serum samples from pregnant women were tested for anti-CMV IgM and IgG antibodies using lysate-based ELISAs and avidity testing. Anti-CMV IgM antibodies against recombinant p52 and anti-CMV IgG antibodies against recombinant glycoprotein B (gB) were also determined by ELISA. All assays were performed and interpreted according to the manufacturer's instructions.

RESULTS

For lysate-based IgM, IgG and avidity testing, 84.6 % of samples yielded conclusive results in a total of 1156 tests, while 15.4 % needed follow-up testing of a consecutive sample. Anti-p52 CMV IgM and anti-gB CMV IgG testing produced conclusive results for 92.8 % of samples in a total of 1026 tests, while 7.2 % samples required follow-up testing.

CONCLUSIONS

The first-line use of ELISAs measuring anti-p52 CMV IgM and anti-gB CMV IgG antibodies to test for maternal CMV infection increases the number of conclusive results derived from an initial serum sample while requiring a considerably lower number of tests compared to the lysate-based approach. For day-to-day routines in a diagnostic laboratory, this high efficiency of the recombinant testing approach has significant practical relevance.

The role of the T-cell mediated immune response to Cytomegalovirus infection in intrauterine transmission

INTRODUCTION

Prognostic markers for fetal transmission of Cytomegalovirus (CMV) infection during pregnancy are poorly understood. Maternal CMV-specific T-cell responses may help prevent fetal transmission and thus, we set out to assess whether this may be the case in pregnant women who develop a primary CMV infection.

METHODS

A multicenter prospective study was carried out at 8 hospitals in Spain, from January 2017 to April 2020. Blood samples were collected from pregnant women at the time the primary CMV infection was diagnosed to assess the T-cell response. Quantitative analysis of interferon producing specific CMV-CD8+/CD4+ cells was performed by intracellular cytokine flow cytometry.

RESULTS

In this study, 135 pregnant women with a suspected CMV infection were evaluated, 60 of whom had a primary CMV infection and samples available. Of these, 24 mothers transmitted the infection to the fetus and 36 did not. No association was found between the presence of specific CD4 or CD8 responses against CMV at the time maternal infection was diagnosed and the risk of fetal transmission. There was no transmission among women with an undetectable CMV viral load in blood at diagnosis.

CONCLUSIONS

In this cohort of pregnant women with a primary CMV infection, no association was found between the presence of a CMV T-cell response at the time of maternal infection and the risk of intrauterine transmission. A detectable CMV viral load in the maternal blood at diagnosis of the primary maternal infection may represent a relevant biomarker associated with fetal transmission.

Risk Factors for Hearing Loss at Birth in Newborns With Congenital Cytomegalovirus Infection

Importance

With a prevalence between 0.2% and 6.1% of all live births, congenital cytomegalovirus (cCMV) infection is a major cause of congenital nonhereditary sensorineural hearing loss. Despite the large amount of research on cCMV-related hearing loss, it is still unclear which newborns are at risk of hearing loss.

Objective

To identify independent risk factors for cCMV-related congenital hearing loss and predictors of hearing loss severity at birth.

Design, Setting, and Participants

This cross-sectional study of newborns with cCMV infection used data included in the Flemish CMV registry that was collected from 6 secondary and tertiary hospitals in Flanders, Belgium, over 15 years (January 1, 2007, to February 7, 2022). Data were analyzed March 3 to October 19, 2022. Patients were included in the study after confirmed diagnosis of cCMV infection and known hearing status at birth. Patients who presented with other possible causes of sensorineural hearing loss were excluded.

Main Outcomes and Measures

Primary outcome was hearing status at birth. Clinical, neurological, and laboratory findings along with the timing of seroconversion and blood viral load were separately considered as risk factors. Binary logistic regression was performed to identify independent risk factors for congenital hearing loss in newborns with cCMV. Effect sizes were measured using Hedges g, odds ratio, or Cramer V.

Results

Of the 1033 newborns included in the study (553 of 1024 [54.0%] boys), 416 (40.3%) were diagnosed with symptomatic cCMV infection and 617 (59.7%) with asymptomatic cCMV infection. A total of 15.4% of the patients (n = 159) presented with congenital hearing loss; half of them (n = 80 [50.3%]) had isolated hearing loss. The regression model revealed 3 independent risk factors for congenital hearing loss: petechiae at birth (adjusted odds ratio [aOR], 6.7; 95% CI, 1.9-23.9), periventricular cysts on magnetic resonance imaging (MRI; aOR, 4.6; 95% CI, 1.5-14.1), and seroconversion in the first trimester (aOR, 3.1; 95% CI, 1.1-9.3). Lower viral loads were seen in patients with normal hearing compared with those with congenital hearing loss (median [IQR] viral load, 447.0 [39.3-2345.8] copies per milliliter of sample [copies/mL] vs 1349.5 [234.3-14 393.0] copies/mL; median difference, -397.0 [95% CI, -5058.0 to 174.0] copies/mL).

Conclusions and Relevance

Findings of this cross-sectional study suggest that newborns with cCMV infection and petechiae at birth, periventricular cysts on MRI, or a seroconversion in the first trimester had a higher risk of congenital hearing loss. Clinicians may use these risk factors to counsel parents in the prenatal and postnatal periods about the risk of congenital hearing loss. Moreover, linking clinical features to hearing loss may provide new insights into the pathogenesis of cCMV-related hearing loss. The importance of viral load as a risk factor for congenital hearing loss remains unclear.

Predicting Outcome of Congenital Cytomegalovirus Infection by Differentiating and Revisiting Severe versus Mild Prenatal Imaging Features

INTRODUCTION

Our objective was to evaluate the outcome of fetuses with first- and second-trimester fetal cytomegalovirus infection (CMVi) according to prenatal imaging patterns, especially fetuses presenting with mild imaging features (MF), being currently of uncertain prognosis.

MATERIAL AND METHODS

In a retrospective study of 415 suspected CMVi cases, 59 cases were confirmed. Among prenatal imaging features, microcephaly, cortical disorder, and cerebellar hypoplasia as well as severe IUGR and fetal hydrops were considered as severe imaging features (SF). Other imaging features were considered as MF. Postnatal outcome was classified as "normal outcome," "mild sequelae" characterized mainly by sensorineural disorder (SND) and "severe sequelae" characterized by cognitive impairment.

RESULTS

Only first-trimester (T1) and second-trimester (T2) CMVi cases were included in our study (n = 49) since all third-trimester cases (n = 10) had normal imaging and outcome. Sixteen fetuses had normal prenatal imaging and normal outcome, except one showing SND. Abnormal ultrasound findings were present in 33 fetuses, including SF noted in 16 fetuses, related exclusively to first-trimester CMVi. Termination of pregnancy was performed in 18 cases. Twelve first-trimester infected fetuses presented SF, whereas 6 fetuses (T1: n = 5, T2: n = 1) presented isolated MF. Four fetal deaths were encountered. Live-born babies with abnormal imaging included 10 fetuses with MF and one with SF. Among the 10 live babies with isolated MF, SND was encountered in 5 cases, whereas 5 children demonstrated normal outcome. Overall, 50% of our babies showing MF suffered from SND. No case of cognitive disorders was reported in babies showing only MF.

CONCLUSION

SF were encountered only in first-trimester CMVi and should be distinguished from MF. Among our 10 live babies with prenatal MF following first- or second-trimester infection, 50% showed SND, whereas none presented severe sequelae. In 16 fetuses displaying normal fetal imaging, SND was encountered in one first-trimester case (6%).

New data on efficacy of valacyclovir in secondary prevention of maternal-fetal transmission of cytomegalovirus

OBJECTIVE

Congenital cytomegalovirus (CMV) infection is the leading cause of non-genetic hearing and neurological deficits. The aim of our study was to evaluate the efficacy and safety of valacyclovir (VCV) treatment in preventing CMV transmission to the fetus after maternal primary infection.

METHODS

This was a retrospective, multicenter study evaluating the rate of maternal-fetal CMV transmission in pregnancies with maternal primary CMV infection treated with VCV at a dosage of 8 g per day (VCV group) compared with a control group of untreated women. Each case underwent virological testing to confirm maternal primary infection and to provide accurate dating of onset of infection. The primary outcome was the presence of congenital CMV infection at birth diagnosed based on polymerase chain reaction analysis of saliva, urine and/or blood samples. The efficacy of VCV treatment was assessed using logistic regression analysis adjusted for a propensity score.

RESULTS

In total, 143 patients were included in the final analysis, of whom 59 were in the VCV group and 84 were in the untreated control group. On propensity-score-adjusted analysis, VCV treatment was significantly associated with an overall reduction in the rate of maternal-fetal CMV transmission (odds ratio, 0.40 (95% CI, 0.18-0.90); P = 0.029). The rate of maternal-fetal CMV transmission, determined at birth, in the VCV vs control group was 7% (1/14) vs 10% (1/10) after periconceptional maternal primary infection (P = 1.00), 22% (8/36) vs 41% (19/46) after first-trimester maternal primary infection (P = 0.068) and 25% (2/8) vs 52% (14/27) after second-trimester maternal primary infection (P = 0.244). When analyzing the efficacy of VCV treatment according to maternal viremia at treatment initiation, there was a trend towards greater efficacy when patients were viremia-positive (21% vs 43%; P = 0.072) compared with when they were viremia-negative (22% vs 17%; P = 0.659). Maternal side effects associated with VCV were mild and non-specific in most cases.

CONCLUSION

Our findings indicate that VCV treatment of pregnant women with primary CMV infection reduces the risk of maternal-fetal transmission of CMV and may be effective in cases with primary infection in the first and second trimesters. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.

Early neurodevelopmental outcomes in children with asymptomatic congenital CMV infection

BACKGROUND

Approximately 85-90% of congenital cytomegalovirus infections (cCMV) are asymptomatic. Few studies have investigated early and long-term neurodevelopmental outcomes in children with asymptomatic cCMV (acCMV), and the data is contradictory. In the present study, we did investigate the effect of cCMV asymptomatic infection on neurological outcomes and in cognitive, language and motor development at 6 months of age.

METHODS

Fifty-six children with cCMV asymptomatic infection were followed for 6 months, as part of a long-term surveillance program, examining their neurological and developmental outcomes. Neurological examination and Bayley-III Scales were performed.

RESULTS

Clinical evaluation revealed that early neurological outcomes were essentially normal, with minor neurological deficits (i.e., tone abnormalities) in a subgroup of patients. Bayley-III scores were substantially in the normal range, with 14% showing a score less than 85 (-1SD) in the Motor Scale. Children's neurological and neurodevelopmental outcomes at 6 months of age did not differ according to the trimester of infection.

CONCLUSIONS

Some infants with cCMV asymptomatic infection may present minor neurological abnormalities in early stages of life. It seems useful to monitor this population for early and late neurodevelopmental sequelae.

Targeted screening for congenital cytomegalovirus infection: clinical, audiological and neuroimaging findings

OBJECTIVE

To evaluate clinical, audiological and neuroimaging findings in a cohort of infants diagnosed with congenital cytomegalovirus (cCMV) infection after failure at newborn hearing screening.

METHODS

A prospective observational study in the Netherlands, using the existing newborn hearing screening infrastructure for well babies. Between July 2012 and November 2016, cytomegalovirus (CMV) PCR testing of neonatally obtained dried blood spots (DBS) was offered to all infants who failed newborn hearing screening. Clinical, neuroimaging and audiological data were collected.

RESULTS

DBS of 1374 infants were successfully tested and 59 were positive for CMV (4.3%). Data of 54 infants were retrieved. Three were small for gestational age and six had microcephaly. Forty-eight (89%) had sensorineural hearing loss (SNHL), of whom half had unilateral SNHL. In both unilaterally and bilaterally affected children, the majority of the impaired ears had severe or profound hearing loss. Neuroimaging abnormalities were found in 40 of 48 (83%) children who had evaluable cranial ultrasound and/or cerebral MRI. The abnormalities were mild in 34, moderate in 3 and severe in 3 infants. The degree of SNHL and the severity of neuroimaging abnormalities were found to be correlated (p=0.002).

CONCLUSIONS

The yield of targeted cCMV screening following newborn hearing screening failure was eight times higher than the estimated national birth prevalence of cCMV. The majority of this cohort of infants with clinically unsuspected cCMV disease had confirmed SNHL, neuroimaging abnormalities and lower than average birth weights and head circumferences. Newborns who fail newborn hearing screening should be tested for CMV to ensure appropriate clinical, neurodevelopmental and audiological follow-up.

Perinatal Cytomegalovirus Infection

PURPOSE OF REVIEW

There have been recent advances in the field of congenital CMV infection (cCMV) related to antiviral treatment of pregnant women and infants, the implementation of newborn CMV screening programs, and the frequency and diagnosis of complications among infected children. In addition, postnatal CMV infection (pCMV) is increasingly recognized as a potential cause of long-term sequelae in addition to acute complications among preterm infants, raising important questions related to treatment, and prevention.

RECENT FINDINGS

High-dose valacyclovir appears to be safe and effective for the prevention of cCMV among women with first-trimester primary CMV infection. New studies reveal high rates of vestibular dysfunction and neuropsychiatric manifestations among children with cCMV. Some studies report associations between pCMV and long-term consequences, including neurodevelopmental delay and bronchopulmonary dysplasia, among very low birth weight infants, in addition to high risk of sepsis and death acutely, which has motivated efforts to eliminate the virus from breast milk by different methods.

SUMMARY

More long-term complications of cCMV are increasingly recognized among children previously thought to be asymptomatic. Although a preventive CMV vaccine may be achievable, strategies to reduce the burden of cCMV disease include maternal education about risk-reduction behaviors, antiviral treatment of pregnant women with primary infection, and newborn screening to allow timely, appropriate care. Similarly, although it remains unclear if pCMV causes long-term problems, there is growing interest in identifying and preventing disease from CMV infections among preterm infants.

Predicting Early Vestibular and Motor Function in Congenital Cytomegalovirus Infection

OBJECTIVES

Congenital cytomegalovirus (cCMV) can affect vestibular function, which is an important cornerstone for early motor development. This study aims to identify risk factors for early vestibular dysfunction with severe repercussions on the motor outcome.

METHODS

This prospective cohort study included 169 cCMV-patients with complete vestibular assessment (lateral video Head Impulse Test and cervical Vestibular Evoked Myogenic Potentials) before the age of 18 months (mean 8.9, standard deviation 3.27 months). Motor results using the Alberta Infant Motor Scale were collected in 152 of these patients. Logistic and linear regression models were applied to identify risk factors for the vestibular and motor outcomes, respectively.

RESULTS

The odds of developing early vestibular dysfunction were 6 times higher in patients presenting with hearing loss at birth compared to those born with normal hearing (p = .002). Within the latter group, significant predictors for vestibular dysfunction were (delayed-onset) hearing impairment at the time of vestibular testing (p = .003) and the presence of periventricular cysts on magnetic resonance imaging (p = .005). Remarkably, none of the patients infected during the third trimester of pregnancy (n = 14) developed early vestibular dysfunction. On average, vestibular-impaired patients had a z-score on the Alberta Infant Motor Scale that was 1.17 points lower than patients without vestibular deficit (p < .001).

CONCLUSION

Early vestibular loss can have a significant adverse effect on motor development. Hearing and cranial imaging findings could facilitate the widespread implementation of a (targeted) vestibular assessment approach in the cCMV-population.

LEVEL OF EVIDENCE

3 Laryngoscope, 2022.

Predictors of cochleovestibular dysfunction in children with congenital cytomegalovirus infection

The purpose of this study is to assess the predictive factors of both hearing and vestibular impairment in congenitally cytomegalovirus-infected children (cCMV) through a multivariate analysis of clinical and imaging characteristics collected during pregnancy and at birth. This retrospective study was conducted between March 2014 and March 2020, including confirmed congenitally CMV-infected children with a complete vestibular and hearing assessment. Data concerning pregnancy, date of infection, clinical characteristics, and symptomatology at birth were collected. In total, 130 children were included, with a median age of 21 months. Eighty-three children (64%) presented with an inner ear impairment (both cochlear and vestibular impairment). Sex, modality of maternal infection (seroconversion or reactivation), pregnancy term, weight and head circumference at birth, neonatal clinical signs of infection, and treatment were not significantly correlated with inner ear impairment. However, multivariate analysis confirmed that there are two independent predictive factors of inner ear impairment: antenatal imaging lesions (OR_a = 8.02 [1.74; 60.27], p-value = 0.01) and infection during the first trimester (OR_a = 4.47 [1.21; 19.22], p-value = 0.03). Conversely, infections occurring during the second trimester were rarely associated with inner ear impairment: 4/13 (31%) in our series, with vestibular impairment alone (4/4) and no hearing loss. None of the children infected during the third trimester developed inner ear dysfunction.

CONCLUSION

Besides the symptomatic status of the CMV infection at birth, we found that antenatal imaging brain damage and early infection (mainly during the first trimester) constitute the two best independent predictive factors of inner ear involvement in congenitally CMV-infected children.

WHAT IS KNOWN

• Congenital cytomegalovirus infection is the leading infectious cause of neurological disabilities and sensorineural hearing loss in children and responsible of vestibular disorders, which are probably underestimated. • No articles have yet defined the predictive factors of the entire inner ear impairment (vestibule and cochlea).

WHAT IS NEW

• The timing of the infection during pregnancy (first and second trimester, ORa=4.47) and antenatal imaging lesions (ORa=8.02) are independently predictive (in a multivariate analysis) of inner ear involvement. • The symptomatic status at birth is a poor predictor of inner ear impairment.

Emerging Concepts in Congenital Cytomegalovirus

Over a century of research has focused on improving our understanding of congenital cytomegalovirus (cCMV), yet it remains the most common congenital infection in the United States, affecting 3 to 6 per 1000 live born infants each year. Pregnancies affected by cCMV are at a heightened risk of spontaneous abortion and intrauterine fetal demise. Neonates born with cCMV are also at substantial risk for long-term neurodevelopmental sequelae and disability, including sensorineural hearing loss, even those born without clinically apparent disease. Considerable progress has been made in recent years in study of the epidemiology and transmission of cCMV, developing better diagnostic strategies, implementing newborn screening programs, improving therapeutics, and launching vaccine trials. In this article, we review recent developments in the understanding of the virology and immunobiology of cytomegalovirus. We further discuss how this knowledge informs our understanding of the pathophysiology of cCMV and directs strategies aimed at improving outcomes and quality of life for congenitally infected children. We also provide an update on the epidemiology of cCMV in the United States, evolving scientific understanding of maternal-fetal transmission, enhanced screening approaches, and recognition of neonatal and long-term sequelae. Finally, we review the current landscape of pediatric cCMV research and provide recommendations for novel and high-priority areas for future investigation.

Neutralizing Antibodies to Human Cytomegalovirus Recombinant Proteins Reduce Infection in an Ex Vivo Model of Developing Human Placentas

Human cytomegalovirus (HCMV) is the leading viral cause of congenital disease and permanent birth defects worldwide. Although the development of an effective vaccine is a public health priority, no vaccines are approved. Among the major antigenic targets are glycoproteins in the virion envelope, including gB, which facilitates cellular entry, and the pentameric complex (gH/gL/pUL128-131), required for the infection of specialized cell types. In this study, sera from rabbits immunized with the recombinant pentameric complex were tested for their ability to neutralize infection of epithelial cells, fibroblasts, and primary placental cell types. Sera from rhesus macaques immunized with recombinant gB or gB plus pentameric complex were tested for HCMV neutralizing activity on both cultured cells and cell column cytotrophoblasts in first-trimester chorionic villus explants. Sera from rabbits immunized with the pentameric complex potently blocked infection by pathogenic viral strains in amniotic epithelial cells and cytotrophoblasts but were less effective in fibroblasts and trophoblast progenitor cells. Sera from rhesus macaques immunized with the pentameric complex and gB more strongly reduced infection in fibroblasts, epithelial cells, and chorionic villus explants than sera from immunization with gB alone. These results suggest that the pentameric complex and gB together elicit antibodies that could have potential as prophylactic vaccine antigens.

Anatomical and diffusion-weighted imaging of brain abnormalities in third-trimester fetuses with cytomegalovirus infection

OBJECTIVES

In this study of cytomegalovirus (CMV)-infected fetuses with first-trimester seroconversion, we aimed to evaluate the detection of brain abnormalities using magnetic resonance imaging (MRI) and neurosonography (NSG) in the third trimester, and compare the grading systems of the two modalities. We also evaluated the feasibility of routine use of diffusion-weighted imaging (DWI) fetal MRI and compared the regional apparent diffusion coefficient (ADC) values between CMV-infected fetuses and presumed normal, non-infected fetuses in the third trimester.

METHODS

This was a retrospective review of MRI and NSG scans in fetuses with confirmed first-trimester CMV infection performed between September 2015 and August 2019. Brain abnormalities were recorded and graded using fetal MRI and NSG grading systems to compare the two modalities. To investigate feasibility of DWI, a four-point rating scale (poor, suboptimal, good, excellent) was applied to assess the quality of the images. Quantitative assessment was performed by placing a freehand drawn region of interest in the white matter of the frontal, parietal, temporal and occipital lobes and the basal ganglia, pons and cerebellum to calculate ADC values. Regional ADC measurements were obtained similarly in a control group of fetuses with negative maternal CMV serology in the first trimester, normal brain findings on fetal MRI and normal genetic testing.

RESULTS

Fifty-three MRI examinations of 46 fetuses with confirmed first-trimester CMV infection were included. NSG detected 24 of 27 temporal cysts seen on MRI scans, with a sensitivity of 78% and an accuracy of 83%. NSG did not detect abnormal gyration visible on two (4%) MRI scans. Periventricular calcifications were detected on two MRI scans compared with 10 NSG scans. While lenticulostriate vasculopathy was detected on 11 (21%) NSG scans, no fetus demonstrated this finding on MRI. MRI grading correlated significantly with NSG grading of brain abnormalities (P < 0.0001). Eight (15%) of the DWI scans in the CMV cohort were excluded from further analysis because of insufficient quality. The ADC values of CMV-infected fetuses were significantly increased in the frontal (both sides, P < 0.0001), temporal (both sides, P < 0.0001), parietal (left side, P = 0.0378 and right side, P = 0.0014) and occipital (left side, P = 0.0002 and right side, P < 0.0001) lobes and decreased in the pons (P = 0.0085) when compared with non-infected fetuses. The ADC values in the basal ganglia and the cerebellum were not significantly different in CMV-infected fetuses compared with normal controls (all P > 0.05). Temporal and frontal ADC values were higher in CMV-infected fetuses with more severe brain abnormalities compared to fetuses with mild abnormalities.

CONCLUSIONS

Ultrasound and MRI are complementary during the third trimester in the assessment of brain abnormalities in CMV-infected fetuses, with a significant correlation between the grading systems of the two modalities. On DWI in the third trimester, the ADC values in several brain regions are abnormal in CMV-infected fetuses compared with normal controls. Furthermore, they seem to correlate in the temporal area and, to a lesser extent, frontal area with the severity of brain abnormalities associated with CMV infection. Larger prospective studies are needed for further investigation of the microscopic nature of diffusion abnormalities and correlation of different imaging findings with postnatal outcome. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.

Cytomegalovirus infection in a single-centre Australian neonatal cohort

AIM

Congenital cytomegalovirus (cCMV) is the most common infectious cause of congenital malformation, non-genetic sensorineural hearing loss and neurodevelopmental sequelae in childhood. The primary aim of this retrospective cohort study was to identify the birth and neurodevelopmental outcomes of neonates diagnosed with symptomatic and asymptomatic cCMV in a large regional tertiary referral hospital.

METHODS

This was a retrospective cohort study of laboratory-based cCMV diagnoses in neonates born at a single study centre between January 2005 and January 2020. Audit of medical records was undertaken to evaluate maternal characteristics, symptom patterns, radiological and neurodevelopmental outcomes of neonates meeting the laboratory diagnostic criteria during the first 24 months.

RESULTS

There were 45 neonates with proven CMV infection and 27 mothers with proven infection with an associated pregnancy outcome. Nineteen neonates were born at term (>37 weeks). Of these, 32 (71.1%) neonates had a significant intercurrent comorbidity and 22 (48.9%) neonates were reported to have a degree of delay in one or more developmental domains. A large proportion (77.3%) of the symptomatic untreated neonates had an unknown history of maternal infection compared to the asymptomatic (10.0%) and symptomatic treated (53.8%) neonates (P = 0.001).

CONCLUSION

Up to half of the neonates with cCMV were at risk of developing a degree of developmental delay at our centre. Whether these outcomes are related primarily to CMV infection or are confounded by the co-existence of prematurity is unclear and needs further evaluation in prospective studies.

HLA-E restricted cytomegalovirus UL40 peptide polymorphism may represent a risk factor following congenital infection

BACKGROUND

Congenital cytomegalovirus immunopathogenesis is largely unknown and multifactorial due to the complex interactions between viral, maternal, placental, and child factors. Polymorphisms in the HLA-E binding UL4015-23 peptide mimics HLA-E complexed peptides from certain HLA-A, -B, -C and -G alleles, which regulate the cellular immune response driven by natural killer-cells (NK) and CD8 + T cells. The aim of this study was to compare UL4015-23 peptides distribution in congenital CMV and the counterpart HLA Class I peptides in a healthy cohort to investigate risk factors and markers for cCMV disease. In this 10-year retrospective study, the UL40 gene was directly sequenced from 242 clinical samples from 199 cases of congenital CMV (166 children and 33 pregnant or breast feeding women). Distribution of HLA-E binding UL4015-23 peptides was analyzed and compared to those of HLA Class I observed in a cohort of 444 healthy individuals.

RESULTS

Nineteen different HLA-E binding UL4015-23 peptides were found. Three of them (VMAPRTLIL, VMAPRTLLL, VMAPRTLVL) were found in 88.3% of UL40 and 100% of HLA Class I of healthy individuals. In contrast, 15 of them (10.7%) were not found in HLA Class I. The VMAPRTLFL peptide was found in 1% of UL40 and all HLA-G alleles. Significant differences in peptide (VMAPRTLIL, VMAPRTLLL, VMAPRTLVL, other UL4015-23 peptides, other HLA Class I peptides) distribution between UL4015-23 from congenital CMV and HLA-A, -B, -C and -G from healthy individuals were found.

CONCLUSIONS

Our findings suggest that a mismatch between UL4015-23 peptides and HLA Class I peptides between children and mothers might play a role in congenital CMV disease, and it may account for differences in outcome, morbidity and sequelae.

Congenital lymphocytic choriomeningitis virus: A review

INTRODUCTION

Lymphocytic choriomeningitis virus (LCMV) uses rodents such as mice and hamsters as its principal reservoir. When women acquire LCMV during pregnancy because of contact with rodents, it can lead to congenital LCMV infection, which is associated with high mortality and morbidity. Although the number of cases reported in the literature is increasing, LCMV is rarely mentioned because a history of exposure to rodents is uncommon and mostly unknown.

OBJECTIVES

The main objective of this article was to summarize all morphological, antenatal, and postnatal abnormalities that may suggest a congenital LCMV infection.

METHODS

We reviewed PubMed case reports and case series where an antenatal and/or a postnatal description of at least one case of congenital LCMV infection was documented.

RESULTS

We found 70 cases of congenital LCMV infection, 68 of which had antenatal or postnatal brain abnormalities, which were mainly chorioretinitis (59/70), hydrocephaly (37/70), microcephaly (22/70), ventriculomegaly (11/70) and periventricular calcifications (11/70). Antenatal and postnatal extracerebral abnormalities were mainly small for gestational age, ascites, cardiomegaly or anemia. Other organ damage was rare, but could include skin abnormalities, hydrops or hepatosplenomegaly. Seventy percent (49/70) of cases had major cerebral abnormalities that could have been detected by antenatal ultrasound examination. Congenital LCMV infection is associated with a significant mortality rate (30%) and survivors often have severe neurologic sequelae.

CONCLUSION

LCMV is a rare congenital infection, but awareness of the various prenatal ultrasound morphological abnormalities should be improved, and LCMV should be considered when first-line etiological explorations are negative, especially when the mother's medical history indicates exposure to rodents.

Neurodevelopmental outcomes of infants born to mothers with SARS-CoV-2 infections during pregnancy: a national prospective study in Kuwait

BACKGROUND

An increasing proportion of women are infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) during pregnancy. Intrauterine viral infections induce an increase in the levels of proinflammatory cytokines, which inhibit the proliferation of neuronal precursor cells and stimulate oligodendrocyte cell death, leading to abnormal neurodevelopment. Whether a maternal cytokine storm can affect neonatal brain development is unclear. The objective of the present study was to assess neurodevelopmental outcomes in neonates born to mothers with SARS-CoV-2 infections during pregnancy.

METHODS

In this prospective cohort study, the neurodevelopmental status of infants (N = 298) born to women with SARS-CoV-2 infections during pregnancy was assessed at 10-12 months post-discharge using the Ages and Stages Questionnaire, 3rd edition (ASQ-3). The ASQ-3 scores were classified into developmental delays (cutoff scores ≤ 2 standard deviations (SDs) below the population mean) and no delays (scores > 2 SDs above the population mean).

RESULTS

The majority (90%) of the infants born to mothers with SARS-CoV-2 infections during pregnancy had favorable outcomes and only 10% showed developmental delays. Two of the 298 infants tested positive for SARS-CoV-2, and both had normal ASQ-3 scores. The majority of the pregnant women had SARS-CoV-2 infections during their third trimester. The risk of developmental delays among infants was higher in those whose mothers had SARS-CoV-2 infections during the first (P = 0.039) and second trimesters (P = 0.001) than in those whose mothers had SARS-CoV-2 infections during the third trimester.

CONCLUSION

The neurodevelopmental outcomes of infants born to mothers with SARS-CoV-2 infections seem favorable. However, more studies with larger sample sizes and longer follow-up periods are required.

Long-term ocular and visual outcomes following symptomatic and asymptomatic congenital CMV infection: a systematic review protocol

INTRODUCTION

Cytomegalovirus (CMV) is one of the most common congenitally acquired infections worldwide. Visual impairment is a common outcome for symptomatic infants, with long-term ophthalmic surveillance often recommended. However, there are no clear guidelines for ophthalmic surveillance in infants with asymptomatic disease. We aim to conduct a systematic review to establish the overall prevalence and incidence of eye and vision related disorders following congenital CMV infection (cCMV).

METHODS AND ANALYSIS

A systematic review and meta-analysis (pending appropriate data for analysis) of cross-sectional and longitudinal studies will be conducted. The PubMed, Embase and CINAHL databases will be searched up to 29 March 2022 without date or language restrictions. Studies will be screened by at least two independent reviewers. Methodological quality of included studies will be assessed using the Joanna Briggs Institute tool. The primary outcome measures will be incidence and/or prevalence of vision impairment or ophthalmic disorders in patients with symptomatic and asymptomatic cCMV infection. A narrative synthesis will be conducted for all included studies. The overall prevalence will be estimated by pooling data using a random-effects model. Heterogeneity between studies will be estimated using Cochran's Q and the I² statistics. Egger's test will be used to assess for publication bias.

ETHICS AND DISSEMINATION

Ethical approval is not required as there is no primary data collection. Study findings will be disseminated at scientific meetings and through publication in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

This is not a clinical trial, but the protocol has been registered: CRD42021284678 (PROSPERO).

Describing the impact of maternal hyperimmune globulin and valaciclovir on the outcomes of CMV infection in pregnancy: a systematic review

Cytomegalovirus is the leading infectious cause of congenital neurological disabilities. Valaciclovir and CMV hyperimmune globulin may reduce vertical transmission and sequelae in neonates. A systematic review on valaciclovir and CMV hyperimmune globulin in preventing vertical transmission or reducing sequelae in neonates was conducted to 3 September 2021. Valaciclovir as a preventative strategy was supported by a well-conducted randomised controlled trial. Evidence supporting valaciclovir as a treatment strategy was limited to observational studies at moderate risk of bias. CMV hyperimmune globulin was not supported as a preventative strategy in two RCTs, which contrasted with observational studies. Evidence favouring CMV hyperimmune globulin as a treatment strategy was limited to observational studies at moderate risk of bias. The role of valaciclovir and CMV hyperimmune globulin in CMV infection in pregnancy is still being defined. Valaciclovir to prevent vertical transmission has the highest quality evidence in favour of use.