Evaluation and management of cytomegalovirus-associated congenital hearing loss

Ophthalmic Complications, Diagnosis, and Treatment of Congenital Human Cytomegalovirus Infection

Background: Human cytomegalovirus (hCMV) is the most common etiological agent of congenital infections seen in newborns. Among the most commonly observed complications in children with congenital human cytomegalovirus infection are those affecting the visual system. Ocular complications of congenital CMV (cCMV) are a topic rarely addressed in the literature, which prompted the authors to update the available knowledge with the latest data. Methodology: English-language literature published between April 2000 and November 2023 (PubMed, NIH, Google Scholar) was analyzed for ocular complications of cCMV. The data obtained were categorized according to the ocular area involved and the incidence. A compilation of criteria for the symptomatic form of cCMV was also created. Results: The cCMV complications described in the literature affect all parts of the visual system: the anterior segment, the posterior segment, the posterior visual pathways, and the visual cortex. The most commonly described ocular complication of cCMV is choroidal and retinal scarring. Conclusions: Ophthalmic complications of cCMV can cause severe visual disturbances. Ophthalmic diagnosis in newborns should include hCMV PCR testing, which has the highest sensitivity and specificity. In the symptomatic form of cCMV, treatment should be instituted according to recommendations. A consensus should be established for screening of primary hCMV infection in pregnant women, the way in which to define the symptomatic form of cCMV, and the appropriateness and standards of treatment for primary hCMV infection in pregnant women.

Coalition for Global Hearing Health Hearing Care Pathways Working Group: Guidelines for Clinical Guidance for Readiness and Development of Evidence-Based Early Hearing Detection and Intervention Programs

Editor's Note: The following article discusses the timely topic Clinical Guidance in the areas of Evidence-Based Early Hearing Detection and Intervention Programs. This article aims to discuss areas of services needed, guidance to countries/organizations attempting to initiate early hearing detection and intervention systems. Expert consensus and systematic/scoping reviews were combined to produce recommendations for evidence-based clinical practice. In Ear and Hearing, our long-term goal for the Point of View article is to stimulate the field's interest in and to enhance the appreciation of the author's area of expertise. Hearing is an important sense for children to develop cognitive, speech, language, and psychosocial skills. The goal of universal newborn hearing screening is to enable the detection of hearing loss in infants so that timely health and educational/therapeutic intervention can be provided as early as possible to improve outcomes. While many countries have implemented universal newborn hearing screening programs, many others are yet to start. As hearing screening is only the first step to identify children with hearing loss, many follow-up services are needed to help them thrive. However, not all of these services are universally available, even in high-income countries. The purposes of this article are (1) to discuss the areas of services needed in an integrated care system to support children with hearing loss and their families; (2) to provide guidance to countries/organizations attempting to initiate early hearing detection and intervention systems with the goal of meeting measurable benchmarks to assure quality; and (3) to help established programs expand and improve their services to support children with hearing loss to develop their full potential. Multiple databases were interrogated including PubMed, Medline (OVIDSP), Cochrane library, Google Scholar, Web of Science and One Search, ERIC, PsychInfo. Expert consensus and systematic/scoping reviews were combined to produce recommendations for evidence-based clinical practice. Eight essential areas were identified to be central to the integrated care: (1) hearing screening, (2) audiologic diagnosis and management, (3) amplification, (4) medical evaluation and management, (5) early intervention services, (6) family-to-family support, (7) D/deaf/hard of hearing leadership, and (8) data management. Checklists are provided to support the assessment of a country/organization's readiness and development in each area as well as to suggest alternative strategies for situations with limited resources. A three-tiered system (i.e., Basic, Intermediate, and Advanced) is proposed to help countries/organizations at all resource levels assess their readiness to provide the needed services and to improve their integrated care system. Future directions and policy implications are also discussed.

Computational designing of a novel subunit vaccine for human cytomegalovirus by employing the immunoinformatics framework

Human cytomegalovirus (HCMV) is a widespread virus that can cause serious and irreversible neurological damage in newborns and even death in children who do not have the access to much-needed medications. While some vaccines and drugs are found to be effective against HCMV, their extended use has given rise to dose-limiting toxicities and the development of drug-resistant mutants among patients. Despite half a century's worth of research, the lack of a licensed HCMV vaccine heightens the need to develop newer antiviral therapies and vaccine candidates with improved effectiveness and reduced side effects. In this study, the immunoinformatics approach was utilized to design a potential polyvalent epitope-based vaccine effective against the four virulent strains of HCMV. The vaccine was constructed using seven CD8+ cytotoxic T lymphocytes epitopes, nine CD4+ helper T lymphocyte epitopes, and twelve linear B-cell lymphocyte epitopes that were predicted to be antigenic, non-allergenic, non-toxic, fully conserved, and non-human homologous. Subsequently, molecular docking study, protein-protein interaction analysis, molecular dynamics simulation (including the root mean square fluctuation (RMSF) and root mean square deviation (RMSD)), and immune simulation study rendered promising results assuring the vaccine to be stable, safe, and effective. Finally, in silico cloning was conducted to develop an efficient mass production strategy of the vaccine. However, further in vitro and in vivo research studies on the proposed vaccine are required to confirm its safety and efficacy.Communicated by Ramaswamy H. Sarma.

The association between late-onset keratitis in congenital cytomegalovirus infection: A nationwide population-based cohort study

AIM

To estimate the relationship between congenital cytomegalovirus (CMV) infection and late-onset keratitis via use of the National Health Insurance Research Database (NHIRD) of Taiwan.

METHODS

We yielded this retrospective cohort study and subjects with congenital CMV infection, which according to the diagnostic codes and laboratory exam, were selected as our study group that diagnosed with congenital CMV infection. Each participant in the study group was matched to four individuals without the non-congenital CMV infection by propensity-score matching (PSM) process and the latter served as the control group. The main outcome is the late-onset keratitis that occurs one year after the congenital CMV infection diagnosis. We applied Cox proportional hazard regression to produce the adjusted hazard ratio (HR) and corresponding 95% confidence interval (CI) of late-onset keratitis between two groups.

RESULTS

There were 426 (7.4%) and 1,516 (6.5%) events of keratitis in the study and control groups. The study group revealed significantly higher ratio of late-onset keratitis than control group after adjusting many confounders (adjusted HR: 1.14, 95% CI: 1.02-1.27), and the cumulative probability of keratitis in the study group was also higher than control group. For the subgroup analysis, the existence of severe congenital CMV infection was significantly correlated to the late-onset keratitis in individuals with congenital CMV infection (adjusted HR: 1.48, 95% CI: 1.01-2.70; P < 0.05).

CONCLUSION

The congenital CMV infection is related to higher rate of late-onset keratitis, especially for those with severe form.

[Triggers and predictors of development and formation of sensorineural hearing loss]

The purpose of the study is to review the results of scientific researches in recent years in an expanded interdisciplinary view of the problem of etiopathogenesis of sensorineural hearing loss, as well as the role of comorbidities and triggers in the formation of persistent changes in the audio-receiving part of the auditory analyzer.

Comprehensive medical evaluation of pediatric bilateral sensorineural hearing loss

Children with bilateral sensorineural hearing loss (SNHL) should undergo a comprehensive medical evaluation to determine the underlying etiology and help guide treatment and counseling. In this article, we review the indications and rationale for medical evaluation of pediatric bilateral SNHL, including history and physical examination, imaging, genetic testing, specialist referrals, cytomegalovirus (CMV) testing, and other laboratory tests. Workup begins with a history and physical examination, which can provide clues to the etiology of SNHL, particularly with syndromic causes. If SNHL is diagnosed within the first 3 weeks of life, CMV testing should be performed to identify patients that may benefit from antiviral treatment. If SNHL is diagnosed after 3 weeks, testing can be done using dried blood spots samples, if testing capability is available. Genetic testing is oftentimes successful in identifying causes of hearing loss as a result of recent technological advances in testing and an ever-increasing number of identified genes and genetic mutations. Therefore, where available, genetic testing should be performed, ideally with next generation sequencing techniques. Ophthalmological evaluation must be done on all children with SNHL. Imaging (high-resolution computed tomography and/or magnetic resonance imaging) should be performed to assess for anatomic causes of hearing loss and to determine candidacy for cochlear implantation when indicated. Laboratory testing is indicated for certain etiologies, but should not be ordered indiscriminately since the yield overall is low.

Comprehensive Analysis of Human Cytomegalovirus- and HIV-Mediated Plasma Membrane Remodeling in Macrophages

The plasma membrane (PM) must be overcome by viruses during entry and release. Furthermore, the PM represents the cellular communication compartment and the immune system interface. Hence, viruses have evolved sophisticated strategies to remodel the PM, for instance to avoid immune sensing and clearance of infected cells. We performed a comprehensive analysis of cell surface dysregulation by two human-pathogenic viruses, human cytomegalovirus (HCMV) and human immunodeficiency virus type 1 (HIV-1), in primary macrophages, which are classical antigen-presenting cells and orchestrators of the immune system. Scanning ion conductance microscopy revealed a loss of roughness and an overall smooth phenotype of HCMV-infected macrophages, in contrast to HIV-1 infection. This phenotype was also evident on the molecular level. When we screened for cell surface receptors modulated by HCMV, 42 of 332 receptors tested were up- or downregulated, whereas HIV-1 affected only 7 receptors. In particular CD164, CD84, and CD180 were targeted by HCMV. Mechanistically, HCMV induced transcriptional silencing of these receptors in an interferon (IFN)-independent manner, and expression was reduced not only by lab-adapted HCMV but also by clinical HCMV isolates. Altogether, our plasma membrane profiling of human macrophages provides clues to understand how viruses evade the immune system and identified novel cell surface receptors targeted by HCMV. IMPORTANCE The PM is a key component that viruses have to cope with. It is a barrier for infection and egress and is critically involved in antiviral immune signaling. We hence asked the question how two immunomodulatory viruses, HIV-1 and HCMV, dysregulate this compartment in infected macrophages, relevant in vivo targets of both viruses. We employed a contact-free microscopic technique to image the PM of infected cells and performed a phenotypic flow cytometry-based screen to identify receptor modulations on a molecular level. Our results show that HIV-1 and HCMV differentially manipulate the PM of macrophages. While HIV-1-mediated changes are relatively subtle, HCMV induces major alterations of the PM. We identify novel immune receptors manipulated by HCMV and define mechanisms of how HCMV interferes with receptor expression. Altogether, our study reveals differential strategies of how two human-pathogenic viruses manipulate infected cells and identifies potential novel pathways of HCMV immune evasion.

Congenital Human Cytomegalovirus Infection Inducing Sensorineural Hearing Loss

Human cytomegalovirus (HCMV) is the primary cause of congenital infections. Despite its clinical significance, congenital HCMV infection is frequently overlooked clinically since most affected infants are asymptomatic. Sensorineural hearing loss (SNHL) is one of the most widely known disorders caused by congenital HCMV infection. The potential mechanism, however, remains unknown to date. The mechanism by which congenital HCMV infection induces sensorineural deafness has been partly characterized, leading to advancements in diagnosis, therapy, and prevention strategies. HCMV-induced hearing loss primarily involves immune responses, the release of inflammatory factors by natural killer (NK) cells, apoptosis of cochlear spiral ganglion, and potential changes due to vascular dysfunction. The diagnosis of HCMV induced SNHL includes serological examination to mothers, imaging, and amniotic fluid examination. Ganciclovir, mainly used for antiviral therapy and behavioral prevention, can, to some degree, prevent congenital HCMV infection. The role of HCMV infection in hearing loss needs further investigation since the mechanism of hearing loss caused by cytomegalovirus infection is not well understood. Although some advancement has been made in diagnosing and treating SNHL, more improvement is needed. A comprehensive understanding of cytomegalovirus’s pathogenesis is of key importance for preventing, diagnosing, and treating SNHL.

Audiologic Status of Children with Confirmed Cytomegalovirus Infection: a Case Series

BACKGROUND

Congenital cytomegalovirus (CMV) infection is the most common non-genetic cause of sensorineural hearing loss (SHNL) in children. Only about 10% to 15% of children with congenital CMV are symptomatic, and most are not diagnosed at birth. About 7% to 15% of clinically asymptomatic patients may develop later complications, including SNHL, which is the most common sequela in clinically asymptomatic patients. In this study, hearing status was investigated in children with confirmed CMV infection and neonatal hearing screening (NHS) histories were reviewed to explore hearing loss caused by CMV.

METHODS

The medical records of 58 children who were diagnosed with confirmed CMV infection were reviewed for clinical symptoms and signs of CMV infection. Hearing status was evaluated with age-appropriate audiological test batteries.

RESULTS

A total of 58 children (M:F = 32:26 patients; age at study: mean, 5.62 years, range, 1-10 years) were diagnosed serologically with CMV infection (14 patients, 21.1%), or diagnosed via PCR of serum (5, 7.9%) and/or PCR from urine (19, 26.8%). Hearing loss was confirmed in 11 children (19.0%), being bilateral in 6 (54.5%), and unilateral in 5 (45.5%). Note that 7 of 17 ears with hearing loss passed NHS and were diagnosed only after re-evaluation when CMV infection was identified.

CONCLUSION

Hearing loss is a serious complication of CMV infection in children. Our results highlight the importance of timely audiological evaluation in children with clinically symptomatic CMV infection even if they pass NHS.

Should hearing targeted screening for congenital cytomegalovirus infection Be implemented?

Since 2013, after Utah became the first state to implement hearing targeted early CMV screening, a national debate has been percolating about whether this approach should be introduced nationally. Currently Utah, Iowa, Connecticut, and New York have passed legislation mandating early CMV screening, and over 100 birth hospitals across the United States have voluntarily implemented early CMV screening programs as part of their standard of care. We reviewed the evidence related to this approach and used the Wilson and Jungner (1968) criteria to evaluate this method of screening. Based on these criteria, there is substantial rationale and evidence to support a hearing targeted approach to screen for congenital CMV. Given this evidence, we currently recommend that infants who fail newborn hearing screen should undergo CMV screening.

Congenital human cytomegalovirus infection and neurologic diseases in newborns

Objective:

This review aimed to summarize research progress regarding congenital cytomegalovirus (cCMV) infection-related nervous system diseases and their mechanisms.

Data sources:

All literature quoted in this review was retrieved from PubMed and Web of Science using the keywords “Cytomegalovirus” and “Neurologic disease” in English. To identify more important information, we did not set time limits.

Study selection:

Relevant articles were selected by carefully reading the titles and abstracts. Then, different diagnosis and clinical treatment methods for human CMV infection-related neurologic diseases were compared, and the main mechanism and pathogenesis of neurologic damage caused by CMV were summarized from the selected published articles.

Results:

cCMV infection is a major cause of neonatal malformation. cCMV can infect the fetal encephalon during early gestation and compromise neurodevelopment, resulting in varying degrees of neurologic damage, mainly including hearing impairment, central nervous system (CNS) infection, neurodevelopmental disorders, ophthalmic complications, cerebral neoplasms, infantile autism, epilepsy, and other neurologic abnormalities.

Conclusions:

cCMV infection-induced neurodevelopmental abnormalities, which were directly caused by fetal encephalon infection, thus inducing neuroimmune responses to damage nerve cells. Such abnormalities were also caused by suppression of the proliferation and differentiation of neural progenitor cells by CMV's gene products. cCMV infection in the fetal encephalon can also inhibit neuronal migration and synapse formation and indirectly trigger placental inflammation and thus disrupt the oxygen supply to the fetus.