Intelligence and Academic Achievement With Asymptomatic Congenital Cytomegalovirus Infection

Association between White Matter T2 Hyper-Intense Signals in Fetal Brain Magnetic Resonance Imaging and Neurodevelopment of Fetuses with Cytomegalovirus Infection

An association between subtle changes in T2 white matter hyper-intense signals (WMHSs) detected in fetal brain magnetic resonance imaging (fbMRI) and congenital cytomegalovirus (CMV) infection has been established. The research aim of this study is to compare children with congenital CMV infection with neurodevelopment outcome and hearing deficit with and without WMHSs in a historic prospective case study cohort of 58 fbMRIs. Of these, in 37 cases, fbMRI was normal (normal group) and WMHSs were detected in 21 cases (WMHS group). The median infection week of the WMHS group was earlier than the normal fbMRI group (8 and 17 weeks of gestation, respectively). The proportion of infants treated with valganciclovir in the WMHS group was distinctly higher. Hearing impairment was not significantly different between the groups. VABS scores in all four domains were within normal range in both groups. The median score of the motor skills corrected for week of infection was better in the WMHS group. A multivariate analysis using the week of infection interaction variable of WMHS and valganciclovir treatment showed better motor score outcomes in the valganciclovir treatment group despite an earlier week of infection. WMHSs were not associated with neurodevelopmental outcome and hearing deficit. In our cohort, valganciclovir treatment may have a protective effect on fetuses with WMHSs by improving neurodevelopmental outcome.

Neurodevelopmental outcomes of children with congenital cytomegalovirus: a systematic scoping review

BACKGROUND

With the emergence of newborn congenital cytomegalovirus (cCMV) screening programs, more infants are being diagnosed and require long-term follow-up. The objective of the study was to summarize the literature to date on neurodevelopmental outcomes in children with cCMV with attention to study-specific definitions of disease severity (symptomatic vs. asymptomatic).

METHODS

This systematic scoping review included studies of children with cCMV (≤18 years-old) measuring neurodevelopment in ≥1 domain: global, gross motor, fine motor, speech/language, and intellectual/cognitive. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed. PubMed, PsychInfo, and Embase databases were searched.

RESULTS

33 studies met inclusion criteria. Global development most frequently measured (n = 21), followed by cognitive/intellectual (n = 16) and speech/language (n = 8). Most (31/33) studies differentiated children by cCMV severity (symptomatic vs. asymptomatic), definitions of which ranged broadly. 15/21 studies described global development categorically (e.g., normal vs. abnormal). Across studies and domains, children with cCMV generally had equivalent or lower scores (vs. controls or normed measures).

CONCLUSIONS

Variation in definitions of cCMV severity and blunt categorical outcomes may limit the generalizability of findings. Future studies should utilize standardized definitions of disease severity and in-depth measurement and reporting of neurodevelopmental outcomes in children with cCMV.

IMPACT

Neurodevelopmental delays are common among children with cCMV, although gaps in the literature to have made quantification of such delays challenging. Variation in definitions of asymptomatic and symptomatic cCMV as well as the use of categorical outcomes of neurodevelopment (e.g., normal vs. abnormal) limits the generalizability and clinical utility of findings.

Parental Perspectives on Communication from Health Care Providers following a Newborn Diagnosis of Congenital Cytomegalovirus Infection: A Secondary Analysis of a Qualitative Study

The study objective was to identify communication messages that parents of children diagnosed with congenital cytomegalovirus (cCMV) infection reported as essential and helpful. We performed a secondary analysis of focus groups and interviews conducted with 41 parents of children with cCMV who had enrolled in a long-term follow-up cCMV study at an academic medical center. Three groups of parents who had children with cCMV participated in the study: parents with children symptomatic at birth, parents with children asymptomatic at birth who later developed sensorineural hearing loss, and parents with children asymptomatic at birth who remained asymptomatic into adulthood. Using a health marketing approach, we identified six general themes from the focus group sessions: initial diagnosis, likely health outcome(s), comfort and coping, symptom watch, resources, and prevention. Receiving the initial diagnosis was shocking for many parents, and they wanted to know how their child would or could be affected. They valued access to the information, follow-up visits for early detection of hearing loss and other developmental delays, and support from other parents. Parents wished to obtain this information from their pediatrician but felt that experts offered more up-to-date knowledge about prognosis, monitoring, and treatment. With more U.S. states implementing cCMV screening strategies which would lead to more infant diagnoses, it will be necessary for providers to meet parents' expectations and communication needs.

A systematic literature review on the humanistic burden of cytomegalovirus

OBJECTIVE

Cytomegalovirus (CMV) infection is typically asymptomatic in healthy individuals; however, certain populations are vulnerable to infection and may develop serious sequelae. CMV infection may also have a broad impact on humanistic outcomes, including patient health status and quality of life (QoL). We conducted a systematic literature review (SLR) to describe the global humanistic burden of CMV and congenital CMV (cCMV) infections across all age groups.

METHODS

Medline, Embase, and LILACS were searched to identify studies on humanistic outcomes following CMV infection, including health status/QoL and any outcomes in domains such as auditory, cognitive ability, developmental status, intelligence, language, memory, mental health, motor performance, social communication, speech, and vocabulary. The SLR included articles published from 2000-2020 and focused geographically on Australia, Europe, Israel, Japan, Latin America, and North America.

RESULTS

Sixty-three studies met the inclusion criteria. In general, individuals with symptomatic cCMV infection experience a greater burden of disease and more substantial impact on QoL versus those with asymptomatic cCMV infection. Children with hearing loss due to cCMV infection, both symptomatic and asymptomatic, showed improved auditory outcomes following cochlear implantation. Newborns, infants, and children with cCMV infections had worse cognitive outcomes in psychological development, sequential and simultaneous processing, phonological working memory, and attention control versus age-matched controls without cCMV infection. CMV infection was also associated with cognitive decline in elderly populations.

CONCLUSIONS

CMV infection can have substantial, lifelong, heterogenous impacts on humanistic outcomes, including health status and QoL, which should be considered when developing and implementing treatment and prevention strategies.

Brainstem auditory pathway maturation in term neonates with congenital cytomegalovirus infection: a cohort study

Congenital cytomegalovirus infection (cCMVi) is a leading cause of sensorineural hearing loss (SNHL) and developmental delay. Brainstem auditory evoked potentials (BAEPs) recording allows assessment of central auditory pathway maturation in neonates. We aimed to characterize the effect of cCMVi on the maturation of the brainstem auditory pathway in term neonates. We retrospectively reviewed medical records of neonates born with cCMVi in 2010-2018 and characterized their auditory pathway maturation using brainstem auditory-evoked potentials (BAEPs). We compared inter-peak latency differences (IPLDs) of the main BAEP components (I-V, I-III, and III-V) in terms of cCMVi patients and healthy controls and described their changes in cCMVi patients throughout the first year of life. Of 101 cCMVi patients, 57 (56.4%) were considered symptomatic, 6 (5.9%) were small for gestational age, 6 (5.9%) had microcephaly, 4 (4%) had thrombocytopenia, 5 (6.6%) had hepatitis, 2 (2.1%) had retinitis, 47 (49.5%) had typical abnormalities on head ultrasound, 9 (8.9%) developed SNHL, and 34 (59.6%) received antiviral therapy. No significant difference was found between IPLDs of full-term cCMVi patients compared to controls throughout the entire auditory pathway (I-III, III-V, and I-V IPLDs), for both ears (p > 0.05). On serial BAEP examinations, cCMVi patients presented decreased IPLDs throughout the first year of life (p < 0.05 of compared 1st, 2nd, and 3rd BAEPs in both ears).   Conclusions: Intrauterine cytomegalovirus infection does not affect the auditory brainstem maturation process in term neonates. Our findings support previous studies noting the normal neurodevelopmental outcome of asymptomatic cCMVi patients, suggesting antiviral treatment is not warranted in these cases. What is Known: • cCMVi is a leading cause of developmental delay and hearing loss. Treatment is recommended for patients with symptomatic diseases who are at significant risk of long-term sequelae. • It is unknown whether cCMVi affects the central nervous system maturation process. What is New: • We performed a neurophysiological evaluation of brainstem conduction by recording the BAEPs. We found that cCMVi has no significant impact on central conduction times along the auditory pathways in the brainstem at birth nor changes the neuronal maturation process during the first year of life. • Our findings suggest that cCMVi does not universally affect central nervous system maturation, supporting a highly selective approach when considering the benefits of antiviral therapy.

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.

Congenital Cytomegalovirus Screening in Massachusetts Birth Hospitals: A Statewide Survey

This study sought to assess the current state of screening for congenital cytomegalovirus infection in newborns among birth hospitals and newborn nurseries in the state of Massachusetts. A survey assessing hospital protocols for cytomegalovirus testing in newborns was distributed to all birth hospitals and newborn nurseries in Massachusetts from November 2020 to February 2021. 73.3% of hospitals responded to at least one survey question. Of these, fewer than half (48.5%) had any established approach for neonatal cytomegalovirus screening. Salivary polymerase chain reaction was the most common testing modality. Most hospitals did not perform confirmatory testing for positive test results. Most respondents (87.9%) did not know or did not answer how results of cCMV screening were reported to families and who was responsible for coordinating care for cCMV-infected infants. We conclude that congenital cytomegalovirus screening protocols are absent or incomplete in most Massachusetts birth hospitals and newborn nurseries. A cohesive strategy involving standardized education and screening guidelines is needed to reduce the incidence and burden of congenital cytomegalovirus disease on children and their families.

Congenital cytomegalovirus infection diagnostics and management

PURPOSE OF THE REVIEW

Congenital cytomegalovirus infection (cCMV) is the most frequent congenital infection and a leading nongenetic cause of sensorineural hearing loss (SNHL) and brain disease. The purpose of this review is to highlight recent developments in the diagnosis and management of children with cCMV.

RECENT FINDINGS

Progress is being made in the efforts to identify more infants with cCMV, especially those with asymptomatic infection. Largely due to efforts by various advocacy/parent groups, a number of states in the United States and many hospital systems have implemented hearing targeted CMV screening and mandated education of pregnant women about CMV.

SUMMARY

cCMV is an important cause of SNHL and neurologic morbidity worldwide. Early identification of infected children is critical to improve outcomes by providing timely interventions and guidance for long-term follow up. The fact that most infants with cCMV have no abnormal clinical findings, and the need to obtain samples for diagnosis within the first 2-3 weeks of life, makes it challenging to identify a majority of infants with cCMV without universal newborn CMV screening.

Impact of maternal cytomegalovirus seroconversion on newborn and childhood hearing loss triological thesis 2022–2023

Objectives/hypothesis

The objective of this study is to describe long‐term hearing outcomes in infants born to mothers with a known cytomegalovirus (CMV) positivity who were not tested for congenital CMV.

Study type

Clinical research study.

Design

Retrospective cohort study.

Methods

Retrospective chart review was performed for mothers seropositive to CMV. Mother–infant dyads (130) were identified between January 1, 2013 and January 1, 2017. Outcomes data was collected through June 1, 2020. Demographics, risk factors for hearing loss, evidence of CMV infection, other causes of hearing loss, need for speech therapy services, and results of all hearing tests were collected.

Results

All 130 infants were asymptomatic and 5 were tested for congenital CMV. Five were negative for CMV and excluded from analyses. Of the remaining 125, only 1 had low‐viral avidity IgG antibodies. None had IgM antibodies. Four children (3.2%) had hearing loss at last audiogram and one child had delayed onset SNHL due to an enlarged vestibular aqueduct. Speech therapy for communication was required for 33 children (26.4%).

Conclusions

Knowledge of maternal perinatal CMV status can allow for education about possible sequelae of cCMV, as well as trigger an alert for testing babies born to mothers with low‐viral avidity IgG during the first trimester, when the risk of vertical transmission is highest. Also, babies born to CMV positive mothers may be more at risk for communication delays necessitating intervention. Studies focusing on the impact of maternal CMV related to childhood communication deficits could elucidate any direct relationships.

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.

Changes in Valganciclovir Use Among Infants with Congenital Cytomegalovirus Diagnosis in the United States, 2009-2015 and 2016-2019

From 2009-2015 to 2016-2019, the proportion of infants in the US with congenital cytomegalovirus treated with valganciclovir roughly doubled for infants enrolled with employer-sponsored insurance (from 16% to 29%) and Medicaid (from 16% to 36%). The proportion treated with valganciclovir increased for all congenital cytomegalovirus disease severity groups.

Single Nucleotide Polymorphisms of Interleukins and Toll-like Receptors and Neuroimaging Results in Newborns with Congenital HCMV Infection

Congenital cytomegalovirus infection (cCMV) is the most common intrauterine infection with central nervous system (CNS) involvement. There is limited data on the associations between Single Nucleotide Polymorphisms (SNPs) in genes involving the first-line defense mechanism and the risk of CNS damage during cCMV. We investigated the associations between neuroimaging findings and SNPs in genes encoding the following cytokines and cytokine receptors in 92 infants with cCMV: interleukins (IL1B rs16944, IL12B rs3212227, IL28B rs12979860), C-C motif chemokine ligand 2 (CCL2 rs1024611), dendritic cell-specific intercellular adhesion grabbing non-integrin (DC-SIGN rs735240), Toll-like receptors (TLR2 rs5743708, TLR4 rs4986791, TLR9 rs352140). The SNP of IL1B rs16944 (G/A) was associated with a reduced risk of ventriculomegaly on MRI (OR = 0.46, 95% CI, 0.22-0.95; p = 0.03) and cUS (OR = 0.38, 95% CI, 0.0-0.93; p = 0.034). Infants carrying heterozygous (T/C) genotype at IL28B rs12979860 had an increased risk of cystic lesions on cUS (OR = 3.31, 95% CI, 1.37-8.01; p = 0.0064) and MRI (OR = 4.97, 95% CI, 1.84-13.43; p = 0.001), and an increased risk of ventriculomegaly on MRI (OR = 2.46, 95% CI, 1.03-5.90; p = 0.04). No other associations between genotyped SNPs and neuroimaging results were found. This is the first study demonstrating new associations between SNPs of IL1B and IL28B and abnormal neuroimaging in infants with cCMV.

Congenital Human Cytomegalovirus Infection: A Narrative Review of Maternal Immune Response and Diagnosis in View of the Development of a Vaccine and Prevention of Primary and Non-Primary Infections in Pregnancy

Congenital cytomegalovirus infection (cCMV) may affect about 1% of all newborns all over the world as a result of either a primary or recurrent human cytomegalovirus (HCMV) infection. While about 90% of infants affected by cCMV are asymptomatic at birth, the remaining 10% are symptomatic often with neurodevelopmental impairment and sensorineural hearing loss. In view of identifying the best approach to vaccine prevention of cCMV, this review will examine the most important steps made in the study of the immune response to, and diagnosis of, HCMV infection. The maternal immune response and immune correlates of protection are being partially identified with a partial contribution given by our laboratory. The diagnosis of primary infection is often difficult to achieve in the first three months of pregnancy, which is the time primarily involved in virus transmission to the fetus in association with the most severe symptoms and sequelae. Prevention of cCMV is anticipated by prevention of primary infection in early pregnancy by means of different measures, such as (i) behavioral-educational measures, (ii) immunoglobulin administration, (iii) antiviral treatment with valaciclovir. However, the most promising approach to cCMV prevention appears to be the development of a non-living vaccine, including at least three viral antigens: gB, pentamer complex gHgLpUL128L, and pp65, which have been shown to be able to stimulate both the humoral and the cellular arms of the maternal immune response. Primary HCMV infection may be managed in pregnancy by counseling of the couples involved by a team of specialists that includes virologists, obstetricians, infectivologists and neonatologists.

Early-childhood cytomegalovirus infection and children's neurocognitive development

BACKGROUND

Despite a clear association seen in congenitally infected children, the effect of postnatal cytomegalovirus (CMV) infection during early childhood on cognitive development has not yet been determined.

METHODS

CMV-infection status was obtained based on serological measurements when children were 7 years old. Using population-based longitudinal data, we employed multivariate Poisson regression with a robust variance estimator to characterize the relationship between childhood CMV infection and adverse neurocognitive outcomes in children. Suboptimal neurocognitive outcomes were compared between CMV-positive and CMV-negative children using various cognitive assessments from 8 to 15 years of age. Children were evaluated on the cognitive domains of language, reading, memory and general intelligence, with a suboptimal score being >2 standard deviations lower than the mean score. Approximate Bayes factor (ABF) analysis was used to determine the level of evidence for the observed associations.

RESULTS

With adjustment for potential confounders, we observed that early-childhood CMV infection was associated with suboptimal total intelligence quotient (IQ) at 8 years of age [incidence-rate ratio (IRR) = 2.50, 95% confidence interval (CI) 1.35-4.62, ABF = 0.08], but not with suboptimal total IQ at 15 years of age (IRR = 0.97, 95% CI 0.43-2.19, ABF = 1.68). Suboptimal attentional control at 8 years (IRR = 1.74, 95% CI 1.13-2.68, ABF = 0.18) and reading comprehension at 9 years (IRR = 1.93, 95% CI 1.12-3.33, ABF = 0.24) were also associated with CMV infection. ABF analysis provided strong evidence for the association between CMV infection and total IQ at 8 years, and only anecdotal evidence for attentional control at 8 years and reading comprehension at 9 years. All other cognitive measures assessed were not associated with CMV infection.

CONCLUSION

In this large-scale prospective cohort, we observed some evidence for adverse neurocognitive effects of postnatal CMV infection on general intelligence during early childhood, although not with lasting effect. If confirmed, these results could support the implementation of preventative measures to combat postnatal CMV infection.

Clinical outcome and the role of antivirals in congenital cytomegalovirus infection

Congenital cytomegalovirus (cCMV) infection is a leading cause of hearing loss and neurological disabilities in children worldwide. Although a minority of infants with cCMV will have symptoms at a birth, these children are at high risk of long-term sequelae. Most infants with cCMV have no clinical signs at birth (asymptomatic), but 10-15% will develop hearing loss. The diagnosis of cCMV relies on detection of the virus from urine or saliva within the first three weeks of life, with saliva PCR being the preferred method due to ease of collection and high sensitivity of the assay. Measures to prevent mother-to-child transmission of CMV are limited, and antiviral therapy with valganciclovir for 6 months is the standard of care for infants with symptomatic cCMV. As more infants with cCMV are being identified through newborn screening, studies are urgently needed to address antiviral treatment in asymptomatic infants and the implementation of prevention strategies to prevent fetal infection. This article is part of the symposium "New drugs and vaccines for DNA virus infections: a symposium in memory of Mark Prichard."

Prenatal Treatment of Congenital Cytomegalovirus With Valganciclovir: A Case Report

Cytomegalovirus (CMV) is the most common congenital infection and infectious cause of fetal anomaly and neurologic injury. However, treatment strategies for congenital CMV (cCMV) infection during pregnancy remain elusive. We report a case of hydrops fetalis secondary to cCMV infection with minimal sequelae after maternal and subsequent neonatal treatment with valganciclovir.

Economic assessments of the burden of congenital cytomegalovirus infection and the cost-effectiveness of prevention strategies

OBJECTIVE

This is a critical review of published economic analyses on congenital cytomegalovirus infection and strategies for its detection and prevention.

FINDINGS

The review identified four cost-of-illness studies and nine cost-effectiveness analyses: three of vaccination of young women, two of prenatal screening, and four of newborn screening. All reported either large economic costs or favorable cost-effectiveness of interventions. However, sensitivity analyses did not address some of the most critical assumptions.

CONCLUSIONS

Reviewed economic analyses overattributed certain adverse long-term outcomes to congenital cytomegalovirus infection, while other long-term costs were not included. Overall, limited conceptual frameworks, unrepresentative data sources, and unsupported or inadequately documented assumptions regarding outcomes and costs hinder the ability of policymakers to draw conclusions. A major challenge is the limited information on long-term outcomes and costs for representative cohorts of individuals with congenital cytomegalovirus, which further research could helpfully address.

Natural History of Congenital Cytomegalovirus Infection in Highly Seropositive Populations

Maternal preconceptional cytomegalovirus (CMV) immunity does not protect the fetus from acquiring congenital CMV infection (cCMV). Nonprimary infections due to recurrence of latent infections or reinfection with new virus strains during pregnancy can result in fetal infection. Because the prevalence of cCMV increases with increasing maternal CMV seroprevalence, the vast majority of the cases of cCMV throughout the world follow nonprimary maternal infections and is more common in individuals of lower socioeconomic background. Horizontal exposures to persons shedding virus in bodily secretions (young children, sexual activity, household crowding, low income) probably increase the risk of acquisition of an exogenous nonprimary CMV infection and fetal transmission. In addition, more frequent acquisition of new antibody reactivities in transmitter mothers suggest that maternal reinfection by new viral strains could be a major source of congenital infection in such populations. However, the exact frequency of CMV nonprimary infection in seroimmune women during pregnancy and the rate of intrauterine transmission in these women are yet to be defined. Usually, the birth prevalence of cCMV is high (≥7:1000) in highly seropositive populations. There is increasing evidence that the frequency and severity of the clinical and laboratory abnormalities in infants with congenital CMV infection born to mothers with nonprimary CMV infection are similar to infants born after a primary maternal infection. This is particularly true for sensorineural hearing loss, which contributes to one third of all early-onset hearing loss in seropositive populations. This brief overview will discuss the need for more research to better clarify the natural history of cCMV in highly seropositive populations, which, in almost all populations, remains incompletely defined.

Prenatal cytomegalovirus, rubella, and Zika virus infections associated with developmental disabilities: past, present, and future

Prenatal infections have long been recognized as important, preventable causes of developmental disabilities. The list of pathogens that are recognized to have deleterious effects on fetal brain development continues to grow, most recently with the association between Zika virus (ZIKV) and microcephaly. To answer clinical questions in real time about the impact of a novel infection on developmental disabilities, an historical framework is key. The lessons learned from three historically important pathogens: rubella, cytomegalovirus, and ZIKV, and how these lessons are useful to approach emerging congenital infections are discussed in this review. Congenital infections are preventable causes of developmental disabilities and several public health approaches may be used to prevent prenatal infection. When they cannot be prevented, the sequelae of prenatal infection may be treatable. WHAT THIS PAPER ADDS: The list of prenatal infections associated with developmental disabilities continues to increase. Lessons learned from rubella, cytomegalovirus, and Zika virus have implications for new pathogens. Severity of illness in the mother does not correlate with severity of sequelae in the infant.

Congenital Cytomegalovirus Infection

Congenital cytomegalovirus (cCMV) infection is a leading cause of hearing loss and neurological disabilities in children, with the disease burden and disabilities due to cCMV greater than many other well recognized childhood conditions. A minority of infants with cCMV will have symptoms at birth. Infants with symptomatic cCMV are at higher risk for sequelae than those born without symptoms. The majority of infants with cCMV are asymptomatic at birth, but 10%-15% will develop hearing loss. Although clinical symptoms can help predict which infants will have sensorineural hearing loss, among asymptomatic cCMV there are currently no predictors of adverse outcome. The identification of a biomarker to identify those at highest risk of sequelae is highly desirable to target interventions to those who could potentially benefit. Because there is increasing rationale for establishing both targeted and universal screening programs for cCMV in the United States and worldwide, this is an urgent priority.

Congenital Cytomegalovirus and Human Immunodeficiency Virus: Effects on Hearing, Speech and Language Development, and Clinical Outcomes in Children

Prenatal infections can have adverse effects on an infant's hearing, speech, and language development. Congenital cytomegalovirus (CMV) and human immunodeficiency virus (HIV) are two such infections that may lead to these complications, especially when left untreated. CMV is commonly associated with sensorineural hearing loss in children, and it can also be associated with anatomical abnormalities in the central nervous system responsible for speech, language, and intellectual acquisition. In terms of speech, language, and hearing, HIV is most associated with conductive and/or sensorineural hearing loss and expressive language deficits. Children born with these infections may benefit from cochlear implantation for severe to profound sensorineural hearing losses and/or speech therapy for speech/language deficits. CMV and HIV simultaneously present in infants has not been thoroughly studied, but one may hypothesize these speech, language, and hearing deficits to be present with potentially higher severity. Early identification of the infection in combination with early intervention strategies yields better results for these children than no identification or intervention. The purpose of this review was to investigate how congenital CMV and/or HIV may affect hearing, speech, and language development in children, and the importance of early identification for these populations.

The Impact of Asymptomatic Congenital Cytomegalovirus on Adult Quality of Life

OBJECTIVE

Children born with asymptomatic congenital cytomegalovirus infection (AcCMV) have increased risk for hearing loss, which may affect their quality of life into adulthood. We aim to determine quality of life outcomes among adults who were identified at birth with AcCMV compared with controls, using the cohort of the Houston Congenital CMV Longitudinal Study.

METHODS

Quality of life was determined using the self-reported Quality of Life Inventory (QOLI). Sixty-one of 109 AcCMV subjects and 23 of 51 controls completed QOLI. Percentile scores of subjects were compared with percentile scores of controls using Student t tests. QOLI percentile scores were compared among AcCMV subjects with (N = 14) and without hearing loss (N = 47).

RESULTS

There was no difference in mean percentile scores on QOLI between AcCMV subjects (59.8 [SD = 27.6]) and controls (57.3 [SD = 35.3]; p = 0.754). Percentile scores indicate an average overall quality of life classification for AcCMV subjects and controls. There was no difference in mean percentile scores on the QOLI between AcCMV subjects with and without hearing loss (54.8 [SD = 25.2]) and 61.3 [SD = 28.3]; p = 0.440, respectively).

CONCLUSION

Adults born with AcCMV do not seem to have lower ratings of quality of life compared with uninfected controls. Although our study had small sample size, hearing loss does not seem to be a significant predictor of QOLI percentile scores among AcCMV subjects. Quality of life in adulthood does not seem to be affected by an individual's awareness of screening positive for CMV, which supports the notion of "no harm" occurring from universal newborn screening for congenital CMV infection.

Brain Magnetic Resonance Imaging in Congenital Cytomegalovirus With Failed Newborn Hearing Screen

BACKGROUND

In 2013, Utah enacted legislation requiring that infants failing newborn hearing screening be tested for cytomegalovirus infection. As a result, cytomegalovirus-infected infants are being identified because of hearing deficits. The neuroimaging findings in this population have not been characterized.

METHODS

Retrospective medical record review was used to identify patients seen at the University of Utah and Primary Children's Hospitals in Salt Lake City, Utah, who failed newborn hearing screening. A cohort of patients with congenital cytomegalovirus infection, brain magnetic resonance imaging (MRI), and sedated auditory brainstem response testing was studied.

RESULTS

Seventeen patients were identified; 11 (65%) were female. Confirmatory auditory brainstem response testing, performed at a median age 29 days, showed profound hearing loss in 8 (47%) subjects, severe loss in two (12%), moderate loss in two (12%), and mild loss in three (18%); two (12%) subjects had normal hearing. The diagnosis of cytomegalovirus infection was made at a median age 23 days. Brain imaging was performed at a median age 65 days. Ten (59%) subjects had one or more neuroimaging abnormality. White matter lesions were found in eight (47%) subjects, cysts in three (18%), and stroke in two (12%). Polymicrogyria was identified in two (12%) subjects. Seven (41%) subjects had normal brain MRIs.

CONCLUSIONS

These results indicate that most infants whose cytomegalovirus infections were identified after failing newborn hearing screening had abnormal brain MRIs. Our results suggest that brain MRIs should be considered in infants with congenital cytomegalovirus infections who are identified through hearing screening programs.

Cytomegalovirus infection during pregnancy: state of the science

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

Congenital Cytomegalovirus Infection Presenting with Hyperbilirubinemia and Splenomegaly in a Term Infant with Trisomy 21

Congenital cytomegalovirus infection (cCMV) is very common, yet the presentation can be varied, making the diagnosis challenging. However, early diagnosis for treatment with medication in symptomatic cases within the first month of life is critical. Hyperbilirubinemia and splenomegaly are less common manifestations at birth and may be overlooked in the setting of other symptoms, especially in a critically ill neonate. We present a case of a term infant with trisomy 21 who presented with isolated hyperbilirubinemia and splenomegaly and was later diagnosed with congenital CMV.

Inattention and Hyperactivity in Children with Symptomatic and Asymptomatic Congenital Cytomegalovirus

OBJECTIVES

To explore the relationship between congenital cytomegalovirus (CMV) and inattention and hyperactivity among school-aged children.

METHODS

The Behavior Assessment System for Children, Second Edition, parent- and self-report, was completed among children with symptomatic congenital CMV (ScCMV) (n = 36), asymptomatic congenital CMV (AcCMV) (n = 76), and controls (n = 29) enrolled in a longitudinal cohort. The proportions of children with ScCMV, AcCMV, and controls with Attention Problems or Hyperactivity T-scores ever ≥ 65 were compared. Mean T-scores in these domains were also compared and adjusted for IQ.

RESULTS

Children with AcCMV did not differ from controls in the proportion of children with elevated Attention Problems or Hyperactivity T-scores or in mean Attention Problems or Hyperactivity T-scores. Children with ScCMV had a higher proportion of elevated Attention Problems T-scores compared with the AcCMV group but not controls. There were no differences in the proportions of children with elevated Hyperactivity T-scores between ScCMV and AcCMV or control groups. Children with ScCMV had higher mean Attention Problems T-scores versus those with AcCMV and controls and higher mean Hyperactivity T-scores versus those with AcCMV but not controls. After adjustment for IQ, differences in mean Attention Problems or Hyperactivity T-scores were no longer significant.

CONCLUSION

Children with AcCMV are not at increased risk of inattention or hyperactivity compared with controls. However, our study suggests an increased prevalence of inattention and hyperactivity among children with ScCMV. Differences in IQ were confirmed to have a confounding effect. Evaluation for attention-deficit/hyperactivity disorder may be warranted in this population.

The Burden of Congenital Cytomegalovirus Infection: A Prospective Cohort Study of 20 000 Infants in Finland

BACKGROUND

Congenital cytomegalovirus (cCMV) infection is the most common congenital infection and causes significant morbidity. This study was undertaken to evaluate the benefits of screening newborns for cCMV and to understand the cCMV disease burden in Finland.

METHODS

Infants born in Helsinki area hospitals were screened for CMV by testing their saliva with a real-time polymerase chain reaction assay. The CMV-positive infants and matched controls were monitored to determine their neurodevelopmental, audiological, and ophthalmological outcomes at 18 months of age. Griffiths Mental Development Scales, otoacoustic emission and sound field audiometry, and ophthalmologic examination were performed.

RESULTS

Of the 19868 infants screened, 40 had confirmed cCMV infection (prevalence, 2 in 1000 [95% confidence interval, 1.4-2.6 in 1000]). Four (10%) infants had symptomatic cCMV. Griffiths general quotients did not differ significantly between the CMV-positive (mean, 101.0) and control (mean, 101.6) infants (P = .557), nor did quotients for any of the Griffiths subscales (locomotion, personal-social, hearing and language, eye and hand, performance) (P = .173-.721). Four of 54 CMV-positive ears and 6 of 80 CMV-negative ears failed otoacoustic emission testing (P = 1.000). The mean minimal response levels over the frequencies 500 Hz to 4 kHz in the sound field audiometry did not differ between CMV-positive (mean, 34.31-dB hearing level) and control (mean, 32.73-dB hearing level) infants (P = .338). No CMV-related ophthalmologic findings were observed.

CONCLUSIONS

The prevalence of cCMV was low, and outcomes at 18 months of age did not differ between the infected infants and healthy control infants. With such a low burden in Finland, universal newborn screening for cCMV seems unwarranted.

Congenital Cytomegalovirus Infection

Background: Congenital cytomegalovirus (cCMV) is the leading cause of nongenetic congenital hearing loss in much of the world and a leading cause of neurodevelopmental disabilities. Infected babies can be born to women who are seropositive and seronegative prior to pregnancy, and the incidence is approximately 0.6%-0.7% in the United States. Symptoms vary from mild to severe, and hearing loss can be delayed in onset and progressive. Methods: We reviewed the literature to summarize the epidemiology, clinical manifestations, diagnosis, treatment, and future directions of cCMV. Results: The best way to diagnose the infection is with polymerase chain reaction of urine or saliva within 3 weeks after birth, followed by a repeat confirmatory test if positive. Moderately to severely symptomatic neonates should be treated for 6 months with valganciclovir, and some practitioners also choose to treat infants who have isolated hearing loss only. Treatment is not recommended for asymptomatic infants. All infected infants should be screened for hearing loss and neurodevelopmental sequelae. Universal and targeted screening may be cost effective. Currently, no vaccine is commercially available, although multiple candidates are under study. Conclusion: Congenitally acquired cytomegalovirus is found in all communities around the world with a disease burden that is greater than many other well-known diseases. Advances are being made in prevention and treatment; however, improved awareness of the disease among clinicians and patients is needed.

Geographic and Racial Disparities in Infant Hearing Loss

OBJECTIVE

Approximately 1 to 2 of every 1000 American newborns has hearing loss identified by newborn screening. This study was designed to determine if infant hearing loss is more common in socioeconomically disadvantaged communities.

STUDY DESIGN

In this retrospective study, we analyzed electronic medical record data using geostatistical models.

SETTING

Infants were residents of Durham County, North Carolina, born in 2 hospitals of the Duke University Health System. This county includes the city of Durham and surrounding suburban and rural communities.

SUBJECTS AND METHODS

Subjects were hearing-screened newborns, born between 2005 and 2016, whose residential address was in Durham County, North Carolina. This was a retrospective study using medical record data. We used Bayesian regression models with smoothing of coordinate date to identify both spatial and nonspatial predictors of infant hearing loss.

RESULTS

We identified 19,348 infants from Durham County, of whom 675 had failed initial hearing screening and 191 had hearing loss confirmed on follow-up. Hearing loss was significantly associated with minority race (odds ratio [OR], 2.45; 95% confidence interval, 1.97-3.06), as well as lower gestational age and maternal sexually transmitted infections. We identified significant geographic heterogeneity, with a higher probability of hearing loss in poorer urban neighborhoods (local OR range, 0.59-1.39). Neighborhood disadvantage was a significant predictor of hearing loss, as was high local seroprevalence of cytomegalovirus (CMV) among pregnant women.

CONCLUSIONS

Urban, low-income neighborhoods have a high prevalence of infant hearing loss compared with more affluent surrounding communities, particularly among minorities. This distribution may be attributable to congenital CMV infection.

Hearing Trajectory in Children with Congenital Cytomegalovirus Infection

Objectives To compare hearing trajectories among children with symptomatic and asymptomatic congenital cytomegalovirus infection through age 18 years and to identify brain abnormalities associated with sensorineural hearing loss (SNHL) in asymptomatic case patients. Study Design Longitudinal prospective cohort study. Setting Tertiary medical center. Subjects and Methods The study included 96 case patients (4 symptomatic and 92 asymptomatic) identified through hospital-based newborn cytomegalovirus screening from 1982 to 1992 and 72 symptomatic case patients identified through referrals from 1993 to 2005. We used growth curve modeling to analyze hearing thresholds (0.5-8 kHz) by ear with increasing age and Cox regression to determine abnormal findings on head computed tomography scan associated with SNHL (hearing threshold ≥25 dB in any audiometric frequency) among asymptomatic case patients. Results Fifty-six (74%) symptomatic and 20 (22%) asymptomatic case patients had SNHL: congenital/early-onset SNHL was diagnosed in 78 (51%) and 10 (5%) ears, respectively, and delayed-onset SNHL in 25 (17%) and 20 (11%) ears; 49 (32%) and 154 (84%) ears had normal hearing. In affected ears, all frequency-specific hearing thresholds worsened with age. Congenital/early-onset SNHL was significantly worse (severe-profound range, >70 dB) than delayed-onset SNHL (mild-moderate range, 26-55 db). Frequency-specific hearing thresholds were significantly different between symptomatic and asymptomatic case patients at 0.5 to 1 kHz but not at higher frequencies (2-8 kHz). Among asymptomatic case patients, white matter lucency was significantly associated with SNHL by age 5 years (hazard ratio, 4.4; 95% CI, 1.3-15.6). Conclusion Congenital/early-onset SNHL frequently resulted in severe to profound loss in symptomatic and asymptomatic case patients. White matter lucency in asymptomatic case patients was significantly associated with SNHL by age 5 years.

Single-cycle adenovirus vectors in the current vaccine landscape

INTRODUCTION

Traditional inactivated and protein vaccines generate strong antibodies, but struggle to generate T cell responses. Attenuated pathogen vaccines generate both, but risk causing the disease they aim to prevent. Newer gene-based vaccines drive both responses and avoid the risk of infection. While these replication-defective (RD) vaccines work well in small animals, they can be weak in humans because they do not replicate antigen genes like more potent replication-competent (RC) vaccines. RC vaccines generate substantially stronger immune responses, but also risk causing their own infections. To circumvent these problems, we developed single-cycle adenovirus (SC-Ad) vectors that amplify vaccine genes, but that avoid the risk of infection. This review will discuss these vectors and their prospects for use as vaccines.

AREAS COVERED

This review provides a background of different types of vaccines. The benefits of gene-based vaccines and their ability to replicate antigen genes are described. Adenovirus vectors are discussed and compared to other vaccine types. Replication-defective, single-cycle, and replication-competent Ad vaccines are compared.

EXPERT COMMENTARY

The potential utility of these vaccines are discussed when used against infectious diseases and as cancer vaccines. We propose a move away from replication-defective vaccines towards more robust replication-competent or single-cycle vaccines.