Clinical outcome and the role of antivirals in congenital cytomegalovirus infection

Assessment of patients' characteristics associated with the efficacy and safety of oral valganciclovir treatment for infants with symptomatic congenital cytomegalovirus disease

INTRODUCTION

Insurance coverage for oral valganciclovir (VGCV) began in Japan in April 2023 on the basis of results, including our clinical trials for symptomatic congenital cytomegalovirus (CMV) disease. The VGCV treatment is available throughout Japan, so clinicians must consider the likelihood of hearing improvement and the possibility of neutropenia before dosing.

MATERIALS AND METHODS

We performed a substudy of an investigator-initiated, single-arm, prospective, multicenter, clinical trial in which 24 infants with symptomatic congenital CMV disease were orally administered 16 mg/kg VGCV twice daily for 6 months as an intervention. We examined the infants' baseline characteristics associated with improved hearing impairment or a severely reduced neutrophil count.

RESULTS

Of the 24 patients, 4 had normal hearing on assessment of their ear with the best hearing. Hearing impairment improved in 14 patients and did not respond to VGCV treatment in 6 patients at the 6-month hearing assessment. CMV DNA levels in plasma at baseline were higher in patients in whom hearing did not respond to treatment. A neutrophil count <500/mm3 occurred in 5 (21%) patients for the first 6 weeks and in 8 (33%) patients for the first 6 months. A neutrophil count at screening and the lowest neutrophil count over the 6 months showed the highest correlation (r = 0.477, p = 0.019).

CONCLUSIONS

Infants with a low plasma viral load at screening tend to have an improvement in hearing impairment. Clinicians should be aware of neutropenia during VGCV treatment particularly in patients with a low neutrophil count during screening.

Pharmacokinetic and Pharmacodynamic Assessment of Valganciclovir in Infants With Congenital Cytomegalovirus Infection

BACKGROUND

Valganciclovir (VGCV) is administered at a dose of 16 mg/kg 2 times daily for 6 months to treat symptomatic congenital cytomegalovirus (CMV) infections. During the treatment period, approximately 20% of the patients developed grade 3 or higher neutropenia. Currently, information on the pharmacokinetics and pharmacodynamics of ganciclovir, an active metabolite of VGCV, in infants is limited. In the current study, the relationship between ganciclovir concentration and neutropenia was investigated, and a population pharmacokinetic (PPK) model of ganciclovir in infants with symptomatic congenital CMV infection was developed.

METHODS

Japanese infants who were prescribed oral VGCV for symptomatic congenital CMV infections between July 2017 and January 2021 were included. The relationship between the observed trough ganciclovir concentrations and neutrophil counts was examined. PPK analysis was performed to evaluate the covariates affecting the pharmacokinetics of ganciclovir.

RESULTS

Twenty-seven ganciclovir serum samples from 8 patients were analyzed. A moderate negative correlation was observed between the observed trough ganciclovir concentration and neutrophil count. PPK model analysis showed that postmenstrual age (PMA) affected the total body clearance of ganciclovir after correcting for the empirical allometric scaling of body weight. Based on PMA and body weight, a nomogram to achieve the target area under the concentration-time curve from 0 to 24 hours of 40-60 mcg·h·mL-1 of ganciclovir was calculated.

CONCLUSIONS

The relationship between neutrophil count and ganciclovir trough concentration in infants was clarified. The PPK model showed that the dose of VGCV should be reduced in patients with a low PMA to achieve target exposure.

Long-term outcomes of congenital cytomegalovirus infection in children early identified by extended hearing-targeted screening

OBJECTIVES

Congenital Cytomegalovirus (cCMV) has been associated with hearing, vision, and neurodevelopmental long-term sequelae. Despite the social burden associated with the disease, a universally accepted consensus on screening, diagnostic, therapeutic and follow-up approaches has not been reached. The present observational retrospective study aims at describing long-term sequelae and radiological abnormalities associated with cCMV in children early identified by extended hearing-targeted screening and evaluated by audiological follow-up in a single III Level Audiological Referral Center for at least 2 years.

METHODS

Audiological neonatal and follow-up data were available for all subjects. Data collection included clinical neonatal and virological assessment at birth. Ophthalmological, neurodevelopmental and neuroradiological follow-up abnormalities compatible with cCMV sequelae were collected by clinical reports. Spearman's rank correlation coefficient (rho-ρ) was used to evaluate possible correlations among the considered parameters.

RESULTS

61 newborns were identified by extended hearing-targeted cCMV screening and diagnosed mostly (83.6 %) by PCR viral DNA extraction in urine collected within the 15° day of life. Seventeen babies were born preterm, with a mean gestational age of 33.5 weeks. Sixteen patients (26.2 %) were admitted to an Intensive or sub-Intensive Neonatal Care Unit. At birth, 35 newborns were symptomatic (57.3 %), and 19 of them received antiviral treatment by valganciclovir or ganciclovir. Overall, 20 children (32.7 %) were diagnosed with sensorineural hearing loss (SNHL), among them 17 (85 %) were refer at the newborn hearing screening while 3 (15 %) were Pass. 5/20 children (25 %) presented isolated SNHL, while in 15/20 (75 %) children SNHL was associated to other long-term sequelae. In 5 patients (25 %) a progression of the hearing threshold was observed, with a mean age of progression of 26 months of age. Risk factors for progression were a worse final hearing threshold (Spearman's ρ = 0.434; p = 0.0001) and a worse hearing threshold at birth (Spearman's ρ = 0.298; p = 0.020). Thirteen children were fitted with hearing aids, 8 of whom subsequently underwent cochlear implantation. Concerning long term impairments, 10/61 children (17 %) presented a variety of ophthalmological sequelae, while 16/40 cCMV patients (40 %) were diagnosed with neurodevelopmental abnormalities. Language delays were significantly associated with a worse hearing threshold (ρ = 0.582; p = 0.0001) and with other neurocognitive abnormalities (ρ = 0.677, p = 0.0001). 30 children underwent radiological brain evaluation by Magnetic Resonance Imaging, and 63.3 % of them presented abnormalities compatible with cCMV. Mean viral load at birth did not show significant associations with long-term sequelae.

CONCLUSIONS

The study highlights the diverse and significant long-term sequelae of cCMV infection detected through early screening. With a significant proportion of cCMV children developing sensorineural hearing loss, ophthalmological and neurodevelopmental issues, the results emphasize the importance of continuous, multidisciplinary follow-up. Early identification and tailored interventions are crucial for improving the long-term health and quality of life of children affected by cCMV.

"Minimally symptomatic" congenital cytomegalovirus infection: latest data and emerging concepts

PURPOSE OF REVIEW

Universal and targeted screening of newborns for congenital cytomegalovirus (CMV) infection is increasing globally. Questions remain concerning the management of infants who have been identified with congenital CMV infection, especially those with "minimally symptomatic" or clinically inapparent infection. Our objective is to discuss current management of CMV-infected neonates with a focus on less affected infants with or without sensorineural hearing loss (SNHL).

RECENT FINDINGS

Valganciclovir is being prescribed increasingly in neonates with congenital CMV infection for improvement in hearing outcomes through 2 years of age. Treatment initiated in the first month of age is recommended for clinically apparent disease. A recent study showed hearing improvement at 18-22 months of age when therapy was initiated at age 1-3 months in infants with clinically inapparent CMV infection and isolated SNHL.

SUMMARY

Antiviral therapy with either ganciclovir or valganciclovir has shown moderate benefit in prevention of hearing deterioration among infants with clinically apparent CMV infection or isolated SNHL. Sustainability of benefit beyond 2 years of age remains unknown. At present, infants with clinically inapparent CMV infection (normal complete evaluation including hearing) should not receive antiviral therapy. All CMV-infected infants require close audiological and neurodevelopmental follow-up.

Human cytomegalovirus and neonatal infection

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

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

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

The Auditory Pathway in Congenitally Cytomegalovirus-Infected Human Fetuses

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

Estimates of congenital cytomegalovirus-attributable infant mortality in high-income countries: A review

As many as 5%-10% of infants with symptomatic congenital cytomegalovirus (cCMV) disease, or 0.4%-0.8% of all liveborn infants with cCMV infection, die in early infancy in high-income countries. However, estimates are uncertain due to several potential biases that can result from data limitations and study designs. First, infants with cCMV infections who die prior to diagnosis, which usually occurs at 1-4 weeks after birth, may be excluded from both the count of deaths and the denominator of cCMV births, resulting in left truncation and immortal time biases. These 'biases' are features of the data and do not reflect bias on the part of researchers, but understanding the potential existence of threats to validity can help with interpretation of findings. Left truncation of infant deaths occurring prior to diagnosis of cCMV can result in understatement of the burden of infant deaths due to cCMV. Conversely, overestimation of infant deaths associated with symptomatic cCMV may occur in clinical case series owing to greater representation of relatively severely affected infants owing to ascertainment and referral biases. In this review, we summarise the characteristics of 26 studies that reported estimates of cCMV-associated infant deaths, including potential biases or limitations to which those estimates may have been subject. We discuss study designs whose implementation might generate improved estimates of infant deaths attributable to cCMV. More complete estimates of the overall public health impact of cCMV could inform current and future screening, prevention, and vaccine research.

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.

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.

Is CMV PCR of inner ear fluid during cochlear implantation a way to diagnose CMV-related hearing loss?

To evaluate the diagnostic performance of cytomegalovirus (CMV) polymerase chain reaction (PCR) on inner ear fluid collected during cochlear implantation and to assess its interest in current practice. This monocentric prospective study included consecutive children presenting with severe to profound sensorineural hearing loss (SNHL) who were candidates for unilateral and/or bilateral cochlear implantation. The etiology of the SNHL was determined before cochlear implantation when possible. During the surgery, drop-like samples of inner ear fluid and blood were collected. CMV PCR was then performed on both samples. Between January 2017 and September 2021, 113 children with severe to profound SNHL underwent cochlear implantation with inner ear fluid collection. Among these children, 77 of them presented with a known cause of SNHL (68%) and 36 of them had an unknown cause of SNHL at the time of surgery (32%). Sensitivity and specificity of the CMV PCR on inner ear fluid were 60% (95% CI: [49-71]) and 98% (95% CI: [96-100]), respectively. Positive and negative predictive values were 90% (95% CI: [83-97]) and 92% (95% CI: [86-98]), respectively. A sensitivity analysis according to age at cochlear implantation showed a decrease with age.

CONCLUSION

Sampling of inner ear fluid during cochlear implant surgery is an interesting, simple and safe way to diagnose CMV-related hearing loss, especially when the diagnosis of congenital infection can no longer be confirmed. However, the sensitivity decreases with age.

TRIAL REGISTRATION

NCT04724265 What is Known: • Congenital cytomegalovirus infection is the leading infectious cause of neurological disabilities and sensorineural hearing loss in children. In the absence of systematic screening at birth, many cCMV infections go undetected and are often undiagnosed despite the development of sensorineural sequelae.  • Nearly 40% of indications for cochlear implantation are of unknown etiology.

WHAT IS NEW

• Performing CMV PCR on inner ear fluid at the time of cochlear implantation is a safe way with high diagnostic performance (PPV = 90%, NPV = 92%) to detect a CMV-related hearing loss. • This sample may be interesting in cases of unknown cause of hearing loss in order to identify undiagnosed cCMV infections.

An Overview of Cytomegalovirus Infection in Pregnancy

The objective of this review was to bring to attention cytomegalovirus (CMV) infection during pregnancy, taking into consideration all relevant aspects, such as maternal diagnosis, fetal infection and prevention, prenatal diagnosis, and postnatal prognosis. A literature review was performed regarding adult and congenital infection. General information regarding this viral infection and potential related medical conditions was provided, considering the issues of maternal infection during pregnancy, transmission to the fetus, and associated congenital infection management. Prenatal diagnosis includes maternal serum testing and the confirmation of the infection in amniotic fluid or fetal blood. Additionally, prenatal diagnosis requires imaging techniques, ultrasound, and complementary magnetic resonance to assess cortical and extracortical anomalies. Imaging findings can predict both fetal involvement and the postnatal prognosis of the newborn, but they are difficult to assess, even for highly trained physicians. In regard to fetal sequelae, the early diagnosis of a potential fetal infection is crucial, and methods to decrease fetal involvement should be considered. Postnatal evaluation is also important, because many newborns may be asymptomatic and clinical anomalies can be diagnosed when sequelae are permanent.

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.

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.

Newborn Screening by Genomic Sequencing: Opportunities and Challenges

Newborn screening for treatable disorders is one of the great public health success stories of the twentieth century worldwide. This commentary examines the potential use of a new technology, next generation sequencing, in newborn screening through the lens of the Wilson and Jungner criteria. Each of the ten criteria are examined to show how they might be applied by programmes using genomic sequencing as a screening tool. While there are obvious advantages to a method that can examine all disease-causing genes in a single assay at an ever-diminishing cost, implementation of genomic sequencing at scale presents numerous challenges, some which are intrinsic to screening for rare disease and some specifically linked to genomics-led screening. In addition to questions specific to routine screening considerations, the ethical, communication, data management, legal, and social implications of genomic screening programmes require consideration.

Audiovestibular Consequences of Congenital Cytomegalovirus Infection: Greater Vulnerability of the Vestibular Part of the Inner Ear

OBJECTIVES

To investigate the impact of congenital cytomegalovirus infection on cochlear and vestibular function.

DESIGN

This retrospective study conducted between March 2014 and March 2020 included children with confirmed congenital cytomegalovirus infection who underwent a complete audio-vestibular evaluation. It included a bithermal caloric test, a video head impulse test and a cervical vestibular evoked myogenic potential associated with a complete hearing assessment.

RESULTS

The cohort of 130 children included in the study had a median age of 21 months (interquartile range: 12 to 37 months). Eighty-three children (64%) showed an inner ear impairment (both cochlear and vestibular). The vestibular part of the inner ear was significantly more frequently impaired than the cochlear part (ρ = 0.003). Sixty-two children (48%) showed confirmed hearing impairment. The severity of hearing loss was variable, with a high proportion of profound hearing loss (30/62, 48%), which was often bilateral (47/62, 76%). The vestibular assessment showed a canal function disorder in 67 children (88%) and an otolith function disorder in 63 children (83%; ρ = 0.36). The video head impulse test was significantly less altered (64%) compared with the bithermal caloric test (80%; ρ = 0.02) and the cervical vestibular evoked myogenic potential (83%; ρ = 0.009). Only seven out of 83 children (8%) showed hearing loss without vestibular dysfunction, of which only one had a normal hearing screening test at birth. For the children who passed the hearing screening test at birth and presented an inner ear impairment [n = 36, median age: 16 (11 to 34) months], vestibular disorders were later found in 35 children (97%) and 17 of them (47%) developed hearing loss secondarily. This underlines the importance of assessing both vestibular and auditory parts of the inner ear. When comparing the agreement of cochlear and vestibular impairment, the severity and the laterality of the impairment were low [Cohen's kappa 0.31 (0.22 to 0.40) and 0.43 (0.32 to 0.55), respectively].

CONCLUSION

In our study, we demonstrated that although both cochlear and vestibular parts of the inner ear can be impaired by congenital cytomegalovirus infection, the vestibular part seems more often impaired compared with the cochlear part. This underlines the importance of vestibular evaluation in the follow-up of cytomegalovirus-infected children associated with hearing assessment.

An Ethical Analysis of Newborn Congenital Cytomegalovirus Screening

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

Delays in diagnosis and treatment initiation for congenital cytomegalovirus infection - Why we need universal screening

INTRODUCTION

Congenital cytomegalovirus (cCMV) is the leading cause of neurodevelopmental and hearing impairment from in-utero infection. Late diagnosis results in limited treatment options and may compromise long-term outcome.

METHODS

A retrospective audit of infants with cCMV referred to a Tertiary Pediatric Infectious Diseases center from 2012-2021. Data collected included timing of diagnostics, treatment initiation and reasons for delays.

RESULTS

90 infants with confirmed cCMV were included, 46/90 (51%) were symptomatic at birth. Most common reasons for diagnostics in asymptomatic infants were failed newborn hearing screening (17/44, 39%) and antenatal risk-factors (14/44, 32%). Median age at cCMV diagnosis was 3 (range 0-68) and 7 (0-515) days, with median referral age 10 (1-120) and 22 (2-760) days for symptomatic and asymptomatic infants respectively. There was a significant risk of delay in diagnosis (>21 days) for asymptomatic infants [RR 2.93 (1.15-7.45); p = 0.02]. Of asymptomatic infants who received treatment, 13/24 (54%) commenced it within 28 days of life, a significant delay in treatment compared to 30/36 (83%) symptomatic infants [RR 2.75 (1.18-6.43); p = 0.02]. The commonest reason for delayed treatment initiation was delayed first diagnostic test for both symptomatic 4/6 (67%) and asymptomatic infants 9/11 (82%).

CONCLUSIONS

Delays in diagnosis and treatment for cCMV are unacceptably frequent and significantly higher in asymptomatic infants. Our study highlights the need for increased awareness among healthcare professionals, reconsideration of age-targets for Newborn Hearing Screening, and research that addresses the barriers to implementation of universal screening, which would ultimately facilitate prompt diagnosis and management of all infants with cCMV.

Congenital Cytomegalovirus Targeted Screening Implementation and Outcomes: A Retrospective Chart Review

OBJECTIVE

To assess the effectiveness and outcomes of a targeted cytomegalovirus (CMV) testing protocol.

STUDY DESIGN

Retrospective chart review.

SETTING

Tertiary care institution.

METHODS

Targeted screening for CMV in children who did not pass the newborn hearing screening (NHS) was introduced in July 2015 for the level 2 and 3 nurseries at our hospital. In January 2016, this policy was extended to include all nurseries. Retrospective chart review was performed for all newborns who did not pass their NHS between 2013 and 2020. CMV testing rates and related outcomes were compared before and after rollout.

RESULTS

A total of 891 charts were reviewed for infants who did not pass their NHS: 530 (60%) had CMV testing, of which 8 (1.5%) tested positive. Three cases were detected prior to and 5 occurred after initiation of targeted screening. Six CMV+ infants demonstrated hearing loss on confirmatory auditory brainstem response, all of whom began treatment with oral valganciclovir. Hearing remained stable in 3 patients, progressed in 2, and improved in 1. The rate of CMV testing in children who did not pass their NHS increased from 14% to 88% after full implementation of targeted screening (P < .001). The average age at initial infectious disease consultation was significantly younger for infants born after targeted screening (P < .001).

CONCLUSION

Targeted screening is a feasible and effective method to identify CMV+ infants early in life. Implementation of a targeted screening program for CMV in children who do not pass the NHS resulted in significantly higher rates of CMV testing and earlier referral to infectious disease.