Clinical profile of hearing loss in children with congenital cytomegalovirus (CMV) infection: CMV DNA diagnosis using preserved umbilical cord

Testing for genetic and viral etiologies in congenital hearing loss based on a survey of cochlear implant centers: proposed HEARRING group consensus and future directions

BACKGROUND

In cases of congenital sensorineural hearing loss, testing for genetic etiologies and congenital cytomegalovirus (cCMV) infection have become common practice.

AIMS/OBJECTIVES

The purpose of this study is to determine which specific testing methodologies should be used and when.

MATERIAL AND METHODS

We surveyed 20 practicing otolaryngologists across eighteen institutions in thirteen countries about their approach to cCMV, GJB2, and wider genetic testing.

RESULTS

We found 90% of respondents employ all three tests, either in routine or special cases. cCMV testing is widely used, with 95% of respondents incorporating it into their clinical practice. GJB2 testing was employed by 90%. In cases with negative GJB2 test results, a majority of respondents proceeded to wider genetic screening. Test reimbursement was also examined for each test. For cCMV testing, 63.1% reported reimbursement, 68.4% reported reimbursement for GJB2 variant testing and 52.6% reported reimbursement for wider genetic screening.

CONCLUSIONS AND SIGNIFICANCE

A common approach is to perform cCMV and GJB2 testing as the first tests, followed by wider genetic testing. This study offers insight into the prevalence, methodologies, and reimbursement status of these testing methodologies across multiple hearing centers and countries. Current consensus and future directions are described based on the current survey.

Neurobehavioral outcomes of neonatal asymptomatic congenital cytomegalovirus infection at 12-months

BACKGROUND

Congenital cytomegalovirus (cCMV) is the most common congenital viral infection in the United States. Symptomatic infections can cause severe hearing loss and neurological disability, although ~ 90% of cCMV infections are asymptomatic at birth. Despite its prevalence, the long-term neurobehavioral risks of asymptomatic cCMV infections are not fully understood. The objective of this work was to evaluate for potential long-term neurobehavioral sequelae in infants with asymptomatic cCMV.

METHODS

Infants with cCMV were identified from a universal newborn cCMV screening study in a metropolitan area in the midwestern United States. Asymptomatic infants with cCMV were enrolled in a longitudinal neurodevelopmental study (N = 29). Age- and sex-matched healthy control infants (N = 193) were identified from the Baby Connectome Project (BCP), a longitudinal study of brain and behavioral development. The BCP sample supplemented an additional group of healthy control infants (N = 30), recruited from the same participant registry as the BCP specifically for comparison with infants with asymptomatic cCMV. Neurobehavioral assessments and parent questionnaires, including the Mullen Scales of Early Learning, the Repetitive Behavior Scales for Early Childhood (RBS-EC), and the Infant Toddler Social Emotional Assessment (ITSEA) were administered at 12 months of age. Neurobehavioral scores were compared between infants with asymptomatic cCMV and all identified healthy control infants.

RESULTS

Infants with asymptomatic cCMV performed equivalently compared to healthy control infants on the neurobehavioral measures tested at 12 months of age.

CONCLUSIONS

These results indicate that at 12 months of age, infants with asymptomatic cCMV are not statistically different from controls in a number of neurobehavioral domains. Although follow-up is ongoing, these observations provide reassurance about neurobehavioral outcomes for infants with asymptomatic cCMV and inform the ongoing discussion around universal screening. Additional follow-up will be necessary to understand the longer-term outcomes of these children.

Epidemiology, aetiology and diagnosis of congenital hearing loss via hearing screening of 153 913 newborns

BACKGROUND

Congenital hearing loss (HL), one of the most common paediatric chronic conditions, significantly affects speech and language development. Its early diagnosis and medical intervention can be achieved via newborn hearing screening. However, data on the prevalence and aetiology of congenital HL in infants who fail newborn hearing screening are limited.

METHODS

The sample population included 153 913 infants who underwent newborn hearing screening, and the prevalence of congenital HL, defined as moderate to profound bilateral HL (BHL) or unilateral HL (UHL) (≥40 dB HL), in one prefecture of Japan was measured to minimize the loss-to-follow-up rate, a common factor affecting the screening procedure. Comprehensive aetiological investigation, including physiology, imaging, genetic tests, and congenital cytomegalovirus screening, was performed on children diagnosed with congenital HL.

RESULTS

The calculated prevalence of congenital HL was 1.62 per 1000 newborns (bilateral, 0.84; unilateral, 0.77). More than half of the cases with congenital bilateral or severe to profound UHL showed genetic aetiology or cochlear nerve deficiency (CND), respectively. Approximately 4% and 6% of the cases of congenital BHL and UHL were associated with congenital cytomegalovirus infection and auditory neuropathy spectrum disorder, respectively.

CONCLUSIONS

This is an epidemiological and comprehensive aetiological study of congenital HL, as determined via newborn hearing screening according to its severity and laterality, in a large-scale general population of a developed country. Our findings can serve as a reference for optimizing care and intervention options for children with HL and their families.

Maternal and congenital human cytomegalovirus infection: laboratory testing for detection and diagnosis

Human cytomegalovirus (CMV) is the leading cause of congenital infection worldwide and the most common cause of non-genetic sensorineural hearing loss. As there is no vaccine or other specific intervention to prevent congenital CMV infection, there is a need to identify maternal and congenital infections with sensitive and specific testing as early as possible. There is no widely accepted practice for screening during pregnancy or in all newborns for identification of possible cases of congenital CMV. Currently, screening during pregnancy is limited to those identified as at risk followed by fetal and/or neonatal testing when congenital infection is suspected. This review focuses primarily on the current status of laboratory testing for diagnosis of maternal and congenital CMV infections. Primary maternal infection is best diagnosed using serologic testing, including CMV IgM, IgG, and avidity testing, while fetal infection should be assessed by nucleic acid amplification testing (NAAT) of amniotic fluid. Urine and saliva NAATs are the mainstay for diagnosis of congenital CMV in the first 3 weeks of life. Testing of dried blood spots can be useful for diagnosis of congenital CMV outside of the newborn period. The gaps in knowledge such as the prognostic value of viral loads in various sample types are addressed.

Newborn hearing screening program in China: a narrative review of the issues in screening and management

Hearing loss is one of the most common sensory disorders in humans. The purpose of this review is to summarize the history and current status of newborn hearing screening in China and to investigate future developmental trends in newborn hearing screening with the intention of sharing experiences and providing a reference for other populations. In the 1980s, the research on hearing monitoring for high-risk infants led to the gradual development of newborn hearing screening in China. With the continuous improvement of screening technology, the newborn hearing screening program was gradually extended to the whole country and became a government-led multidisciplinary public health program. Genetic screening for deafness has been incorporated into newborn hearing screening in many regions of China to help screen for potential and late-onset deafness in newborns. In the future, it is necessary to further establish and improve whole life-cycle hearing screening and healthcare, conduct screening for congenital cytomegalovirus infection, and create a full-coverage, whole life course hearing screening and intervention system. Screening for deafness in China has been marked by 40 years of achievements, which have been a source of pride for entrepreneurs and comfort for patients and their families. Managing hearing screening data information more efficiently and establishing a quality control index system throughout the whole screening process are of paramount importance. The genetic screening for concurrent newborn hearing and deafness has a great clinical importance for the management of congenital deafness and prevention of ototoxicity. A hearing screening and intervention system across the whole life course should be developed.

Prevalence and Characteristics of Cytomegalovirus Ocular Disease in Children: A Multi-Center Study

Purpose

The objective of this study was to identify the prevalence of CMV ocular disease in children and to identify associated risk factors for ocular involvement.

Design

Retrospective multicenter, cross-sectional study.

Methods

Setting: Hospitalized patients screened for CMV viremia by PCR between 2005 and 2018 at four pediatric referral centers. Participants: Seven-hundred and ninety-three children showed CMV viremia (>135 copies/mL by polymerase chain reaction; PCR). Main Outcomes and Measures: (1) Occurrence of ophthalmologic examination. (2) Presence of CMV ocular disease, defined as retinitis, vasculitis, hemorrhage, optic nerve atrophy, or anterior uveitis in the setting of CMV viremia without other identifiable causes.

Results

A total of 296/793 (37%) underwent ophthalmologic examination following CMV viremia. A total of23/296 patients (8%) had ocular symptoms prompting evaluation while the rest had eye exams for baseline screening unrelated to CMV viremia. Of these, 13 cases (4% of those with an eye exam) with ocular disease were identified (three congenital CMV, five severe combined immunodeficiency disorder (SCID) status post-stem cell transplantation, three hematologic malignancy status post-stem cell transplantation for two of them, one Evans syndrome status post-stem cell transplantation, and one medulloblastoma status post-bone marrow transplantation). No patients with solid organ transplantation developed CMV ocular disease in our cohort.

Conclusion

CMV ocular disease was a rare occurrence in this cohort without an identifiable pattern across sub-groups. Excluding the three congenital CMV cases, nine out of ten patients with CMV ocular disease were status post-stem cell transplantation. We provide integrated screening guidelines based on the best available evidence for this rare condition.

Hearing outcome in congenitally CMV infected children in Finland - Results from follow-up after three years age

OBJECTIVES

Cytomegalovirus (CMV) is the most common congenital infection affecting about 0.6% of all newborns in developed countries. Vertical transmission to fetus can take place either after maternal primary or non-primary CMV infection during pregnancy. It is the most common infectious agent for sensorineural hearing loss (SNHL) in young children. The hearing loss after congenital CMV (cCMV) may be present at birth, or may develop after months or even years. In this study, we evaluated hearing outcome at 3-4 years of age in children (n 32) with cCMV identified in universal saliva CMV-PCR-based screening.

METHODS

Study population consisted of mainly asymptomatic children (median age 3.1 years) with cCMV identified in newborn CMV screening. The type of maternal CMV infection (primary or non-primary) was determined by analyzing CMV antibodies (IgM, IgG and IgG avidity) from preserved maternal serum samples drawn in the end of first trimester of pregnancy. Hearing was evaluated with pure tone audiometry (PTA), or transient-evoked otoacoustic emission (TEOAE) and sound field audiometry (SF).

RESULTS

Unilateral hearing loss occurred in 5/32 (16%) of the children with cCMV. None of the subjects in our cohort had bilateral hearing loss. Hearing loss occurred in 3/15 (20%) of children who were born to mothers with non-primary CMV infection during pregnancy, and in 2/10 (20%) of children whose mother had had a primary CMV infection during the 2-3 trimester. None of the additional 6 children, whose mother had primary infection in the first trimester, had hearing loss by age of 3-4 years. Two children with normal hearing at 1 years age had developed unilateral hearing loss by the age of three.

CONCLUSIONS

Unilateral hearing loss was relatively common among the mainly asymptomatic children with cCMV identified in screening. Long-term follow up of children with cCMV is essential to identify the children with late-onset hearing loss.

High Incidence of Hippocampal Abnormalities in Pediatric Patients with Congenital Cytomegalovirus Infection

BACKGROUND

Congenital cytomegalovirus (CMV) infection exhibits polymicrogyria, intracranial calcification, white matter lesions, and several types of intracranial lesions on magnetic resonance imaging (MRI), in addition to various developmental disorders and epilepsies. However, little is known on the presence of hippocampal abnormality in this affliction. The aim of this study is to clarify the incidence of hippocampal abnormality in congenital CMV infection.

METHODS

Seventeen children diagnosed as having congenital CMV infection along with 17 age-matched pediatric controls were retrospectively evaluated by brain MRI and clinical review. The measurement data were obtained from conventional coronal sections in this retrospective study. Hippocampal malrotation (HIMAL) was defined as a hippocampal diameter ratio (i.e., the ratio of the height and width of the hippocampus) of >0.92.

RESULTS

Hippocampal diameter ratios were significantly higher in the congenital CMV infection group (0.99 [range: 0.70-1.58] on the right side and 0.85 [range: 0.66-1.39] on the left side) than in controls (0.71 [range: 0.58-0.91] and 0.70 [range: 0.50-1.00], respectively). HIMAL was present in 17 of 34 hippocampi (50%) in the congenital CMV infection group and 1 of 34 hippocampi (2.9%) in controls. No correlations were detected between HIMAL and intelligence quotient/developmental quotient or the occurrences of autism spectrum disorder or epilepsy.

CONCLUSION

This study is the first to demonstrate the incidence of hippocampal abnormality to be significantly higher in congenital CMV infection patients than in age-matched controls. Further study is necessary to clarify the associations of HIMAL with other clinical and developmental features.

Etiology of hearing loss affects auditory skill development and vocabulary development in pediatric cochlear implantation cases

BACKGROUND

Cochlear implantation (CI) is an effective treatment for severe-to-profound hearing loss patients and is currently used as the standard therapeutic option worldwide. However, the outcomes of CI vary among patients.

AIMS/OBJECTIVES

This study aimed to clarify the clinical features for each etiological group as well as the effects of etiology on CI outcomes.

MATERIALS AND METHODS

We collected clinical information for 308 pediatric cochlear implant cases, including the etiology, hearing thresholds, age at CI, early auditory skill development, total development, monosyllable perception, speech intelligibility and vocabulary development in school age, and compared them for each etiology group.

RESULTS

Among the 308 CI children registered for this survey, the most common etiology of hearing loss was genetic causes. The genetic etiology group showed the most favorable development after CI followed by the unknown etiology group, syndromic hearing loss group, congenital CMV infection group, inner ear malformation group, and cochlear nerve deficiency group.

CONCLUSIONS AND SIGNIFICANCE

Our results clearly indicated that the etiology of HL affects not only early auditory skill development, but also vocabulary development in school age. The results of the present study will aid in more appropriate CI outcome assessment and in more appropriate intervention or habilitation programs.

Frequency and natural course of congenital cytomegalovirus-associated hearing loss in children

BACKGROUND

Congenital cytomegalovirus-associated hearing loss (cCMV-associated HL) is a common cause of congenital or early-onset deafness. Although cCMV infection has been reported to lead to various types of HL, the natural course of cCMV-associated HL over a long period is not yet known.

OBJECTIVES

To investigate the clinical phenotype of cCMV-associated HL in the largest study to date.

METHODS

Thirty-one CMV-positive children, diagnosed by examining CMV DNA extracted from their dried umbilical cords retrospectively, were divided into unilateral and bilateral HL groups, and their hearing ability was evaluated using pure-tone audiometry and auditory steady-state response over time.

RESULTS

Thirteen patients (41.9%) had unilateral HL and 18 (58.1%) had bilateral HL. In most cases of unilateral cCMV-associated HL, the ear with better hearing maintained a normal hearing threshold. Notably, in most cases of both unilateral and bilateral HL, the ear with worse hearing ultimately showed severe to profound HL.

CONCLUSION

Our findings revealed that the natural course of cCMV-associated HL was different between the cases of unilateral and bilateral HL, as well as between the ears with better or worse hearing in all cases. These findings indicate that accurate diagnosis could enable proper follow-up and management of cCMV-associated HL in children.

Unilateral Sensorineural Hearing Loss in Children Associated With Sjögren's Syndrome

The occurrence of unilateral sensorineural hearing loss (SNHL) during school age is relatively rare and accounts for approximately 6% of all deafness in childhood. We present two cases involving children who were diagnosed with SNHL associated with Sjögren's syndrome (SS). Case 1: An eight-year-old girl with an approximately two-year clinical history of gradual hearing loss was diagnosed with SNHL associated with SS based on histological findings of inflammation in the salivary glands and the presence of serum anti-Sjögren's syndrome-A antibody. Case 2: An eight-year-old boy with acute idiopathic thrombocytopenic purpura in whom unilateral hearing loss, which was not associated with any problems in daily life, was detected during hospitalization and who was finally diagnosed with SNHL and SS. Steroid treatment was ineffective for both patients. The previously unrecognized combination of SNHL with SS should be considered in the diagnosis of unilateral SNHL, even in children.

Cytomegalovirus-A Risk Factor for Childhood Hearing Loss: A Systematic Review

OBJECTIVE

Permanent hearing loss is an important public health issue in children with consequences for language, social, and academic functioning. Early hearing detection, intervention, and monitoring are important in mitigating the impact of permanent childhood hearing loss. Congenital cytomegalovirus (CMV) infection is a leading cause of hearing loss. The purpose of this review was to synthesize the evidence on the association between CMV infection and permanent childhood hearing loss.

DESIGN

We performed a systematic review and examined scientific literature from the following databases: MEDLINE, Ovid MEDLINE(R) Daily and Ovid MEDLINE(R), Embase, and CINAHL. The primary outcome was permanent bilateral or unilateral hearing loss with congenital onset or onset during childhood (birth to 18 years). The secondary outcome was progressive hearing loss. We included studies reporting data on CMV infection. Randomized controlled trials, quasi-experimental studies, nonrandomized comparative and noncomparative studies, and case series were considered. Data were extracted and the quality of individual studies was assessed with the Qualitative Assessment Tool for Quantitative Studies (McMaster University). The quality and strength of the evidence were graded using the Grading of Recommendations Assessment, Development and Evaluation (GRADE). A narrative synthesis was completed.

RESULTS

Sixty-five articles were included in the review. Prevalence of hearing loss at birth was over 33% among symptomatic CMV-infected newborns and less than 15% in asymptomatic infections. This difference in prevalence was maintained during childhood with more than 40% prevalence reported for symptomatic and less than 30% for asymptomatic CMV. Late-onset and progressive hearing loss appear to be characteristic of congenital CMV infections. Definitions of hearing loss, degree of loss, and reporting of laterality varied across studies. All degrees and both bilateral and unilateral loss were reported, regardless of symptomatic and asymptomatic status at birth, and no conclusions about the characteristics of hearing loss could be drawn. Various patterns of hearing loss were reported including stable, progressive, and fluctuating, and improvement in hearing (sometimes to normal hearing) was documented. These changes were reported in children with symptomatic/asymptomatic congenital CMV infection, presenting with congenital/early onset/late-onset hearing loss and in children treated and untreated with antiviral medication.

CONCLUSIONS

Symptomatic and asymptomatic congenital CMV infection should be considered a risk factor for hearing loss at birth and during childhood and for progressive hearing loss. Therefore, CMV should be included as a risk factor in screening and surveillance programs and be taken into account in clinical follow-up of children with hearing loss.

A High Risk of Missing Congenital Cytomegalovirus-Associated Hearing Loss through Newborn Hearing Screening in Japan

It remains unclear to what extent newborn hearing screening (NHS) detects congenital cytomegalovirus (cCMV)-associated sensorineural hearing loss (SNHL) in Japan. This study aimed to clarify the NHS results and audiological characteristics of patients with cCMV-associated SNHL. A total of 541 individuals with unilateral or bilateral hearing loss of unknown etiology were examined for cCMV infection. cCMV infection was defined by the presence of CMV DNA in the dried umbilical cord detected using real-time quantitative PCR. NHS results and audiological data were retrospectively obtained from medical records. Forty-four cases (8.1%) were positive for cCMV infection. Of them, 33 cases underwent NHS and 13 cases (39.4%) passed NHS bilaterally. The pure-tone audiograms of 21 patients were obtained. There were seven cases of unilateral SNHL, five cases of asymmetric bilateral SNHL, and nine cases of symmetric bilateral SNHL. cCMV-related hearing loss is highly heterogeneous, and there is a high risk of missing this condition through NHS.

Paediatric Sudden Sensorineural Hearing Loss: Pooled Analysis and Systematic Review

Sudden sensorineural hearing loss (SSNHL) is defined as hearing loss of ≥30 dB in one or both ears, developing within 3 days, affecting ≥3 contiguous frequencies. It is rare in children, but if untreated can cause significant morbidity. During the critical developmental period, it may cause lifelong social, behavioral, and mental sequelae. Currently, little guidance exists on prognosis and management within a pediatric population. A systematic literature review of pediatric SSNHL on PubMed, EMBASE, and the Cochrane CENTRAL database was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses recommendations. A total of 620 papers met the Medical Subject Headings criteria, of which 14 met analysis criteria-13 were level 4 and 1 was level 2b evidence. A population of 732 individuals was analyzed. Most reported cases of pediatric SSNHL were idiopathic. Other etiologies included viral infection, trauma, ototoxic drugs, and structural abnormalities. Recovery was defined as any improvement in hearing after the initial loss, from "slight" to "complete." Recovery ranged from 20% to 100%, with a pooled rate of 56%. Systemic steroids were the mainstay of treatment, although salvage intratympanic steroid therapy had a role after the failure of systemic steroids. Children with bilateral SSNHL had poorer outcomes than those with unilateral loss, with 29% showing improvement. Two studies reported outcomes with no treatment, for which recovery rate was 7%. This analysis of SSNHL shows that 61% of children with unilateral and 29% of children with bilateral SSNHL demonstrate some recovery, a worse prognosis than adults. Multiple treatment regimens exist, although comparison is challenging owing to inconsistently reported improvement parameters.

Pathobiology and treatment of viral keratitis

Keratitis is one of the most prevalent ocular diseases manifested by partial or total loss of vision. Amongst infectious (viz., microbes including bacteria, fungi, amebae, and viruses) and non-infectious (viz., eye trauma, chemical exposure, and ultraviolet exposure, contact lens) risk factors, viral keratitis has been demonstrated as one of the leading causes of corneal opacity. While many viruses have been shown to cause keratitis (such as rhabdoviruses, coxsackieviruses, etc.), herpesviruses are the predominant etiologic agent of viral keratitis. This chapter will summarize current knowledge on the prevalence, diagnosis, and pathobiology of viral keratitis. Virus-mediated immunomodulation of host innate and adaptive immune components is critical for viral persistence, and dysfunctional immune responses may cause destruction of ocular tissues leading to keratitis. Immunosuppressed or immunocompromised individuals may display recurring disease with pronounced severity. Early diagnosis of viral keratitis is beneficial for disease management and response to treatment. Finally, we have discussed current and emerging therapies to treat viral keratitis.

Genetic Testing for Congenital Bilateral Hearing Loss in the Context of Targeted Cytomegalovirus Screening

OBJECTIVES/HYPOTHESIS

To determine the prevalence of children with genetic hearing loss who are cytomegalovirus (CMV) positive at birth and the relative proportion of genetic and CMV etiology among children with congenital bilateral hearing loss.

STUDY DESIGN

Database review.

METHODS

We performed a review of clinical test results for patients undergoing comprehensive genetic testing for all known hearing loss-associated genes from January 2012 to January 2019. This population was reviewed for reported CMV status and genetic causes of congenital bilateral hearing loss.

RESULTS

In the OtoSCOPE database, 61/4,282 patients were found to have a documented CMV status, and 661/4282 had documented bilateral congenital hearing loss. Two patients were identified who had both a positive CMV result and a genetic cause for their hearing loss. Forty-eight percent of patients with bilateral congenital hearing loss (320/661) were found to have a genetic etiology. In 62% (198/320), the hearing loss was associated with pathogenic variants in GJB2, STRC, SLC26A4 or an Usher syndrome-associated gene.

CONCLUSIONS

We estimate that ~2% of CMV-positive newborns with hearing loss have a known genetic variant as a cause. The subcohort of CMV-positive newborns with symmetric mild-to-moderate bilateral hearing loss will have at least a 7% chance of having pathogenic gene variants associated with hearing loss. In a CMV-positive neonate who failed their newborn hearing screen bilaterally, genetic screening needs to be considered for accurate diagnosis and possible deferment of antiviral treatment.

LEVEL OF EVIDENCE

4 Laryngoscope, 130:2714-2718, 2020.

Cytomegalovirus Retinitis in HIV and Non-HIV Individuals

Cytomegalovirus retinitis (CMVR) is a severe, vision-threatening disease that primarily affects immunosuppressed patients. CMVR is the most common ocular opportunistic infection in human immunodeficiency virus (HIV) infected patients and is the leading cause of blindness in this group; however, the incidence of CMVR in HIV patients has dramatically decreased with antiretroviral therapy. Other causes of immunosuppression, including organ transplantation, hematologic malignancies, and iatrogenic immunosuppression, can also lead to the development of CMVR. Herein, we describe the pathogenesis of CMVR and compare clinical features, epidemiology, and risk factors in HIV and non-HIV infected individuals with CMVR.

The Natural History and Rehabilitative Outcomes of Hearing Loss in Congenital Cytomegalovirus: A Systematic Review

OBJECTIVE

The purpose of this study was to examine the literature regarding the natural history and rehabilitative outcomes of sensorineural hearing loss from congenital cytomegalovirus infections.

DATA SOURCES AND STUDY ELIGIBILITY CRITERIA

A systematic search was performed in PubMed, PsychINFO, CINAHL, and Web of Science to identify peer-reviewed research. Eligible studies were those containing original peer-reviewed research in English addressing either the natural history or rehabilitative outcomes of sensorineural hearing loss (SNHL) in congenital cytomegalovirus (cCMV).

STUDY APPRAISAL AND SYNTHESIS METHODS

Two investigators independently reviewed all articles and extracted data. Bias was assessed using the Cochrane Collaboration's tool and the Newcastle-Ottawa Assessment Scale.

RESULTS

Thirty-six articles were reviewed. Universal screening identifies 0.2 to 1% of newborns with cCMV infection. SNHL ranged from 8 to 32% of infants and was more prevalent in symptomatic versus asymptomatic cases. Nine to 68% of hearing loss occurs in a late or delayed fashion. In 7 to 71% of cases hearing loss is progressive. Cochlear implantation (CI) is a viable option for patients with cCMV associated hearing loss and leads to improvements in hearing and language. There is limited literature comparing rehabilitation outcomes in cCMV and non-cCMV CI recipients.

CONCLUSION

Late onset and progressive hearing loss is seen in children who develop hearing loss from cCMV. Frequent audiologic follow-up is necessary considering the natural history of cCMV hearing loss. Universal screening should be pursued due to the number of asymptomatic children, at birth, who develop late onset/delayed hearing loss. CI is an effective means of improving speech and language in this population.

Congenital Cytomegalovirus Infection and Tetralogy of Fallot: An Unusual Association in a Three-month-old Baby

Congenital cytomegalovirus (cCMV) infection is the leading cause of infant morbidity and mortality worldwide. Despite being associated with significant neurological sequelae in infected infants, it remains an under-recognized public health entity. Symptomatic newborns most frequently display hepatosplenomegaly, petechiae, jaundice, microcephaly, intrauterine growth restriction, chorioretinitis, purpura, and seizures. Progressive sensorineural hearing loss is the most prominent adverse outcome of both symptomatic and asymptomatic CMV infections in infants. We report the case of a three-month-old baby who presented with complaints of progressive jaundice for three months and a two days history of fever associated with one episode of fits. The baby was diagnosed with congenital CMV infection on the basis of positive CMV IgM and IgG and positive maternal serum CMV IgG. Finding a murmur on physical examination prompted echocardiography which revealed Tetralogy of Fallot (TOF). The child was managed with a 6-week course of ganciclovir after which his symptoms improved and he was referred to cardiology for the evaluation of his heart defect. Follow-ups at the clinic have shown normal growth and development. This is the first reported association of cCMV infection with TOF. This case highlights the need to consider the possibility of the presence of heart defects in all infants with cCMV infection in addition to neurodevelopmental abnormalities. Clinicians should maintain a high degree of suspicion for cCMV infection in all neonates to ensure timely intervention and to prevent long-term neurological sequelae.

Implications of dried blood spot testing for congenital CMV on management of children with hearing loss: A preliminary report

INTRODUCTION

Non-genetic, congenital sensorineural hearing loss (cSNHL) is commonly caused by congenital CMV infection (cCMV). Hearing loss related to cCMV is variable in degree, often progressive, and can affect one or both ears.

OBJECTIVES

We sought to examine the outcomes of DBS testing in California, and the hearing outcomes of cCMV-positive children.

METHODS

This is a retrospective study of patients with SNHL of unknown etiology aged 6 months to 17 years old presenting to a tertiary care pediatric center and evaluated for cCMV by DBS testing.

RESULTS

114 children (228 ears) with SNHL of unknown origin were included. 6/114 (5.3%) tested positive for cCMV versus 108/114 (94.7%), who tested negative. None of the cCMV-positive children had symmetric bilateral hearing loss, compared with 56.5% (61/108) of cCMV-negative children (p < 0.05). cCMV-positive children were more likely to have profound SNHL in the worse-hearing ear (5/6 (83%) vs 16/108 (14.9%) of cCMV-negative children, p < 0.001). 86% (5/6) exhibited progressive hearing loss, including progression or new-onset hearing loss in the previously better hearing ear. 3 of the 6 children with cCMV underwent CI.

CONCLUSION

A small proportion of patients presenting with SNHL tested positive on DBS. Of cCMV-positive children, most presented with profound hearing loss in the worse-hearing ear, and 50% of cCMV-positive children developed progressive hearing loss in the initially better-hearing ear. Prognostic information afforded by etiologic confirmation of cCMV infection informed decision-making concerning cochlear implantation in these cases.

A rational approach to identifying newborns with hearing loss caused by congenital cytomegalovirus infection by dried blood spot screening

OBJECTIVE

Congenital cytomegalovirus (cCMV) infection is the most common congenital infection, with the majority of infected newborns having no detectable signs. The aim of this study was to examine the accuracy of our newly developed DBS-based assay as an appropriate mass screening method for cCMV infection.

METHODS

Between May 2011 and October 2016, newborns delivered at six hospitals in Nagano Prefecture, Japan were enrolled prospectively. We employed dried blood spot (DBS)-based assays with real-time quantitative PCR (qPCR).

RESULTS

Prior to the clinical study, confirmation analysis was carried out using positive and negative controls. The sensitivity and specificity of this DBS-based qPCR assay for the detection of CMV DNA were 83 and 97%, respectively. During the study period, 9675 newborns were enrolled. The total recovery rate of DBS was 99.92% (9,667/9,675). From our analysis of the 9,667 samples, 47 DBS samples were found positive by the qPCR test (0.48%), and 9620 (99.5%) DBS samples were CMV-negative.

CONCLUSIONS

The risk of neural disorders associated with cCMV infection is thought likely to increase with CMV viral load in the blood. DBS screening for cCMV may be sufficient in a clinical setting, and offers a realistic and feasible option for universal mass screening.

Analysis of archived newborn dried blood spots (DBS) identifies congenital cytomegalovirus as a major cause of unexplained pediatric sensorineural hearing loss

PURPOSE

Congenital cytomegalovirus (cCMV) infection is the most common non-genetic cause of sensorineural hearing loss (SNHL). However, accurate diagnosis of cCMV as the etiology of SNHL is problematic beyond the neonatal period. This study therefore examined whether cCMV infection could be identified retrospectively in children presenting with unexplained SNHL to a multidisciplinary diagnostic outpatient otolaryngology clinic at an academic medical center in Minnesota.

METHODS

Over a 4-year period, 57 patients with an age range of 3months to 10years with unexplained SNHL were recruited to participate in this study. Informed consent was obtained to test the archived dried blood spots (DBS) of these patients for cCMV infection by real-time PCR, targeting a highly conserved region of the CMV UL83 gene. Results were normalized to recovery of an NRAS gene control. Chart review was conducted to identify subjects who underwent genetic testing and/or neurodiagnostic imaging to investigate possible genetic, syndromic, or anatomical causes of SNHL.

RESULTS

In total, 15 of the 57 children with unexplained SNHL tested positive for CMV DNA in their DBS (26%). A mean viral load of 8.3×10⁴ (±4.1×10⁴) [range, 1×10³-6×10⁵] copies/μg DNA was observed in subjects retrospectively diagnosed with cCMV. No statistically significant correlation was found between viral load and SNHL severity.

CONCLUSIONS

A retrospective DBS analysis demonstrated that 26% of patients presenting with unexplained SNHL in childhood had cCMV. DBS testing is useful in the retrospective diagnosis of cCMV, and may provide definitive diagnostic information about the etiology of SNHL.

Maternal and Placental Factors Associated with Congenital Hearing Loss in Very Preterm Neonates

BACKGROUND

Sensorineural hearing loss (SNHL) is a multifactorial disease that more frequently affects preterm newborns. Although a number of maternal conditions have been reported to be associated with preterm birth, little information is available concerning maternal risk factors for the development of SNHL. We aimed to identify maternal and placental risk factors associated with a "refer" result on the newborn hearing screening (NHS) test and subsequently confirmed SNHL in very preterm neonates.

METHODS

This retrospective cohort study included 267 singleton neonates who were born alive after ≤ 32 weeks. Histopathologic examination of the placenta was performed, and clinical data were retrieved from a computerized perinatal database. Cases with two abnormal findings, "refer" on the NHS test, and presence of SNHL on the confirmation test were retrospectively reviewed based on electronic medical records.

RESULTS

Forty-two neonates (15.7%) showed a "refer" result, and, on the confirmation test, permanent SNHL was identified in 1.87% (5/267) of all neonates. Multivariate regression analysis revealed that the presence of funisitis was independently associated with a "refer" on the NHS test, whereas use of antenatal corticosteroids was statistically significantly associated with a reduced incidence of "refer" on the screening test. Neither histologic chorioamnionitis nor prematurity (as defined by low gestational age and birth weight) was associated with a "refer" on the NHS test. By contrast, multivariate analysis with occurrence of SNHL as a dependent variable identified no significant associations with the parameters studied, probably owing to the small total number of neonates with permanent SNHL.

CONCLUSION

Presence of funisitis was significantly and independently associated with increased risk of abnormal NHS results, while administration of antenatal corticosteroids was related to a normal NHS result. These findings support the hypothesis that a systemic fetal inflammatory response, manifested as funisitis, might play a role in the pathogenesis of SNHL in preterm neonates.

Etiology of single-sided deafness and asymmetrical hearing loss

CONCLUSIONS

The present study revealed that various etiologies are involved in single-sided deafness (SSD), and that the cause of SSD and asymmetrical hearing loss (AHL) differed greatly between congenital/early-onset cases and adult cases. Clarification of the etiology is the first step toward providing appropriate intervention.

OBJECTIVES

The study aimed to clarify the etiology of SSD and AHL patients.

METHODS

The etiology of a total of 527 SSD or AHL patients who visited Shinshu University Hospital between 2006 and 2016 were analyzed by imaging as well as serological tests for mumps virus, and CMV DNA testing.

RESULTS

In our cohort of congenital/early-onset SSD (n = 210), the most prevalent cause in children was cochlear nerve deficiency (43.7%; 87 of 199 patients undergoing CT and/or MRI), followed by CMV infection, mumps infection, anomalies of the inner ear, ANSD, and other rare etiologies. In contrast, half of the adult SSD patients presented with idiopathic sensorineural hearing loss, followed by various types of otitis media, cerebellopontine angle tumor and other rare etiologies.

Clinical Study on 136 Children with Sudden Sensorineural Hearing Loss

Background:

The prevalence of sudden sensorineural hearing loss in children (CSSNHL) is consistently increasing. However, the pathology and prognosis of CSSNHL are still poorly understood. This retrospective study evaluated clinical characteristics and possible associated factors of CSSNHL.

Methods:

One hundred and thirty-six CSSNHL patients treated in Department of Otolaryngology-Head and Neck Surgery and Institute of Otolaryngology at Chinese PLA General Hospital between July 2008 and August 2015 were included in this study. These patients were analyzed for clinical characteristics, audiological characteristics, laboratory examinations, and prognostic factors.

Results:

Among the 136 patients (151 ears), 121 patients (121 ears, 80.1%) were diagnosed with unilaterally CSSNHL, and 15 patients (30 ears, 19.9%) with bilateral CSSNHL. The complete recovery rate of CSSNHL was 9.3%, and the overall recovery rate was 37.7%. We found that initial degree of hearing loss, onset of treatment, tinnitus, the ascending type audiogram, gender, side of hearing loss, the recorded auditory brainstem response (ABR), and distortion product otoacoustic emissions (DPOAEs) had prognostic significance. Age, ear fullness, and vertigo had no significant correlation with recovery. Furthermore, the relevant blood tests showed 30.8% of the children had abnormal white blood cell (WBC) counts, 22.1% had elevated homocysteine levels, 65.8% had high alkaline phosphatase (ALP), 33.8% had high IgE antibody levels, and 86.1% had positive cytomegalovirus (CMV) IgG antibodies.

Conclusions:

CSSNHL commonly occurs unilaterally and results in severe hearing loss. Initial severe hearing loss and bilateral hearing loss are negative prognostic factors for hearing recovery, while positive prognostic factors include tinnitus, gender, the ascending type audiogram, early treatment, identifiable ABR waves, and DPOAEs. Age, vertigo, and ear fullness are not correlated with the recovery. Some serologic indicators, including the level of WBC, platelet, homocysteine, ALP, positive CMV IgG antibody, fibrinogen, and some immunologic indicators, are closely related to CSSNHL.

Cellular mechanisms of noise-induced hearing loss

Exposure to intense sound or noise can result in purely temporary threshold shift (TTS), or leave a residual permanent threshold shift (PTS) along with alterations in growth functions of auditory nerve output. Recent research has revealed a number of mechanisms that contribute to noise-induced hearing loss (NIHL). The principle cause of NIHL is damage to cochlear hair cells and associated synaptopathy. Contributions to TTS include reversible damage to hair cell (HC) stereocilia or synapses, while moderate TTS reflects protective purinergic hearing adaptation. PTS represents permanent damage to or loss of HCs and synapses. While the substrates of HC damage are complex, they include the accumulation of reactive oxygen species and the active stimulation of intracellular stress pathways, leading to programmed and/or necrotic cell death. Permanent damage to cochlear neurons can also contribute to the effects of NIHL, in addition to HC damage. These mechanisms have translational potential for pharmacological intervention and provide multiple opportunities to prevent HC damage or to rescue HCs and spiral ganglion neurons that have suffered injury. This paper reviews advances in our understanding of cellular mechanisms that contribute to NIHL and their potential for therapeutic manipulation.

A Comprehensive Study on the Etiology of Patients Receiving Cochlear Implantation With Special Emphasis on Genetic Epidemiology

Objective:

Cochlear implantation is the most important treatment currently available for profound sensorineural hearing loss. The aim of this study was to investigate the etiology of hearing loss in patients with cochlear implantation, and to compare outcomes.

Methods:

Japanese hearing loss patients who received cochlear implants (CIs) or electric acoustic stimulation (EAS) in Shinshu University hospital (n = 173, prelingual onset: 92, postlingual onset: 81) participated in this study. Invader assay followed by the targeted exon-sequencing of 63 deafness genes using Massively parallel DNA sequencing (MPS) was applied. For prelingual patients, additional imaging examination, cCMV screening, and pediatric examination were performed for precise diagnosis.

Results:

Genetic screening successfully identified the causative mutation in 60% of patients with prelingual onset hearing loss and in 36% of those with postlingual hearing loss. Differences in the kinds of genes identified were observed between the two groups. Although there were marked variations in the outcome of cochlear implantation, patients with specific deafness gene mutations showed relatively good results.

Conclusion:

The present study showed genetic etiology is a major cause of hearing loss in CI/EAS patients. Patients possessing mutations in a number of deafness genes known to be expressed within inner ear have achieved satisfactory auditory performance, suggesting that the identification of the genetic background facilitates the prediction of post-CI performance. MPS is a powerful tool for the identification of causative deafness genes in patients receiving cochlear implantation. Therefore, determination of the involved region inside/outside of the cochlea by identification of the responsible gene is essential.

Correlation Between White Matter Lesions and Intelligence Quotient in Patients With Congenital Cytomegalovirus Infection

BACKGROUND

It is well known that congenital cytomegalovirus infection exhibits white matter and other types of lesions in magnetic resonance imaging (MRI), but little is known on the clinical significance of white matter lesions because they are also present in asymptomatic congenital cytomegalovirus infection. We investigated for relationships among white matter lesions, intelligence quotient, and other neurodevelopmental features.

METHODS

Nine children (five boys and four girls; mean age: 87.4 months, range: 63-127 months) with sensorineural hearing loss (five bilateral and four unilateral) had been diagnosed as having congenital cytomegalovirus infection by positive polymerase chain reaction findings of dried umbilical cords. They were evaluated for the presence of autistic features, tested using Wechsler Intelligence Scale for Children-Fourth Edition for intelligence quotient, and underwent brain MRI to measure white matter lesion localization and volume.

RESULTS

At the time of MRI examination (mean age: 69.4 months, range: 19-92 months), white matter lesions were detected in eight of nine patients. Five subjects were diagnosed as having autism spectrum disorders. We observed increased white matter lesion volume was associated with lower intelligence quotient scores (R(2) = 0.533, P = 0.026) but not with autism spectrum disorders.

CONCLUSIONS

In individuals with congenital cytomegalovirus, an increased white matter lesion volume is associated with lower intelligence quotient scores but not with an increased likelihood of autistic behavior.

Presence of cytomegalovirus in the perilymphatic fluid of patients with profound sensorineural hearing loss caused by congenital cytomegalovirus infection

CONCLUSION

Not all patients diagnosed with congenital infection using umbilical cord assay were found to be positive for CMV-DNA by perilymphatic fluid assay. In addition, a CMV-DNA-positive result was observed in one patient who had not been diagnosed with congenital infection. Sampling of perilymphatic fluid from a large population of patients with congenital SNHL caused by congenital CMV infection or of unknown etiology is required to determine the prevalence of CMV-related profound HL.

OBJECTIVES

Sensorineural hearing loss (SNHL) is one of the most frequent manifestations in patients with congenital cytomegalovirus (CMV) infection. Using dried umbilical cord, a PCR-based assay was recently developed for the retrospective detection of congenital CMV infection. This study analyzed the presence of CMV in the perilymphatic fluid and evaluated differences in the effect of cochlear implantation between CMV-positive and -negative groups.

METHOD

Perilymphatic fluid was collected from each patient at the time of cochlear implantation and analyzed for the presence of CMV using a PCR method.

RESULTS

The perilymphatic fluid in two of the five patients suffering from congenital CMV infection and in one of the 17 patients without congenital CMV infection was found to be positive for CMV.

Hearing loss and congenital CMV infection: a systematic review

BACKGROUND AND OBJECTIVE

Hearing loss caused by congenital cytomegalovirus (cCMV) infection was first observed in 1964. Today cCMV is the most common cause of nonhereditary sensorineural hearing loss in childhood. Our objective was to provide an overview of the prevalence of cCMV-related hearing loss, to better define the nature of cCMV-associated hearing loss, and to investigate the importance of cCMV infection in hearing-impaired children.

METHODS

Two reviewers independently used Medline and manual searches of references from eligible studies and review articles to select cohort studies on children with cCMV infection with audiological follow-up and extracted data on population characteristics and hearing outcomes.

RESULTS

Thirty-seven studies were included: 10 population-based natural history studies, 14 longitudinal cohort studies, and 13 retrospective studies. The prevalence of cCMV in developed countries is 0.58% (95% confidence interval, 0.41-0.79). Among these newborns 12.6% (95% confidence interval, 10.2-16.5) will experience hearing loss: 1 out of 3 symptomatic children and 1 out of 10 asymptomatic children. Among symptomatic children, the majority have bilateral loss; among asymptomatic children, unilateral loss predominates. In both groups the hearing loss is mainly severe to profound. Hearing loss can have a delayed onset, and it is unstable, with fluctuations and progression. Among hearing-impaired children, cCMV is the causative agent in 10% to 20%. Despite strict selection criteria, some heterogeneity was found between selected studies.

CONCLUSIONS

This systematic review underscores the importance of cCMV as a cause of sensorineural hearing loss in childhood.

Feasibility and acceptability of targeted screening for congenital CMV-related hearing loss

BACKGROUND

Congenital cytomegalovirus (cCMV) is the most common non-genetic cause of sensorineural hearing loss (SNHL) in children. Ganciclovir has been shown to prevent the continued deterioration in hearing of children with symptomatic cCMV, but some children with cCMV-related SNHL are unidentified in the neonatal treatment period. Neonatal cCMV screening provides an opportunity to identify infants with cCMV-related SNHL who might benefit from early treatment.

OBJECTIVES

To assess the feasibility (ability to take samples before 3 weeks of age and clinical assessment by 30 days of age) and acceptability (maternal anxiety) of targeted CMV testing of infants who are 'referred' for further audiological testing after routine newborn hearing screening programme (NHSP).

METHODS

Parents of infants who have 'no clear responses' on routine NHSP before 22 days of life in London and North East England were approached. Salivary and urine samples were tested by CMV PCR. At recruitment and 3 months, the short form Spielberger State-Trait Anxiety Inventory measured maternal anxiety.

RESULTS

411 infants were recruited. 99% (407/411) returned a sample; 98% (404/411) successfully yielded a CMV result, 6 had cCMV, all diagnosed on salivary samples taken <22 days of age (1.5%; 95% CI 0.6% to 3.2%). Only 50% returned urine samples compared with 99% returning salivary samples (p<0.001). Using saliva swabs 98% were successfully screened for CMV within 3 weeks. All positive screening CMV results were known by day 23, and 5/6 infants with cCMV were assessed within 31 days. Anxiety was not increased in mothers of infants screened for cCMV.

CONCLUSIONS

Targeted salivary screening for cCMV within the NHSP is feasible, acceptable and detects infants with cCMV-related SNHL who could benefit from early treatment.

Evaluation of cortical processing of language by use of positron emission tomography in hearing loss children with congenital cytomegalovirus infection

OBJECTIVE

To predict cochlear implant efficacy and investigate the cortical processing of the visual component of language in profoundly deafened patients with asymptomatic congenital cytomegalovirus (CMV) infection.

METHODS AND CASES

The cortical activity of two children with CMV-related hearing loss was evaluated with fluorodeoxyglucose-positron emission tomography (FDG-PET) with a visual language task before cochlear implantation. Total development and auditory perception ability were assessed one year after implantation.

RESULTS

The two children with CMV-related hearing loss showed activation in the auditory association area where no activation was found in the controls, and exhibited nearly identical cortical activation patterns to those seen in patients with profound congenital hearing loss. In contrast, differences in total development in verbal ability and discrimination of sentences between the two cases were revealed one year after implantation.

CONCLUSION

These results might indicate that the differences of cortical activities according to hearing abilities could have been influenced by CMV infection that involves higher function of the brain directly and/or affects the cochlea peripherally. Additionally, if CMV infection might have affected only the cochlea, these cortical activation patterns were influenced secondary by the time course of hearing loss characterized by CMV infection, which had varied manifestations. Accurate diagnosis and cochlear implantation at the appropriate time are important for successful speech development, and each patient needs a personalized habilitation program based on their etiology and brain function.

Prevalence of DFNB1 mutations among cochlear implant users in Slovakia and its clinical implications

Hereditary etiology plays an important role in bilateral profound deafness as a main indication for cochlear implantation. Mutations in DFNB1 locus account for most of the inherited deafness cases in Caucasians. To provide actual data on mutation prevalence among implanted deaf subpopulation, we performed DNA analysis of GJB2 and GJB6 genes in 131 unrelated Slovak cochlear implant users. Eight previously described causal mutations and one probably pathogenic missense variant (c.127G>A) were detected in the GJB2 gene in 58 (44.28%) subjects. The most common mutation found was c.35delG with frequency 83.02% of all disease alleles, followed by c.71G>A, c.1-3201G>A, c.313_326del14, c.109G>A, 167delT, c.269T>C, and c.333_334delAA. GJB6 deletion delD13S1830 was identified in only one subject, in double heterozygosity with a GJB6 mutation. Thus, the deafness cause could be clearly attributable to DFNB1 mutations in 36.64% of the patients examined. In summary, the mutation profile found in our cohort was similar to the mutation spectrum reported for Central European deaf populations. The mutation prevalence in cochlear implant users was, however, almost by 25% higher than previously established for non-implanted hearing-impaired population in Slovakia. Finally, we also demonstrate a certain variability in deafness onset in patients with causal genotype and coincidence with other risk factors for deafness. Our results underline the importance of genetic tests in all cochlear implant candidates.