Audiological and vestibular symptoms following SARS-CoV-2 infection and COVID-19 vaccination in children aged 5-11 years.

PURPOSE: The present study assessed the prevalence of audio-vestibular symptoms following SARS-COV-2 infection or COVID-19 vaccination among children, comparing the two groups. A further aim was to evaluate whether children with pre-existing unilateral hearing loss were more prone to adverse events. MATERIALS AND METHODS: This retrospective study included children aged 5-11 years with normal hearing or a proven history of unilateral hearing loss who contracted SARS-CoV-2 or received two doses of COVID-19 vaccine. Tinnitus, hyperacusis, aural fullness, otalgia, otorrhea, new-onset hearing loss, vertigo and dizziness were investigated as possible complications of SARS-CoV-2 infection or the COVID-19 vaccine. RESULTS: This study included 272 children (143 boys, 129 girls), with a mean age of 7.8 ± 2.3 years. Among these, 120 were affected by pre-existing unilateral hearing loss. The most common audio-vestibular symptoms reported by children following SARS-CoV-2 infection and COVID-19 vaccination were aural fullness (33/132, 25 %) and dizziness (5/140, 3.6 %), respectively. All symptoms following COVID-19 vaccination resolved within 24 h. Compared to children who received the COVID-19 vaccine, those infected with SARS-CoV-2 had a higher prevalence of tinnitus (p = 0.009), hyperacusis (p = 0.003), aural fullness (p < 0.001), otalgia (p < 0.001), otorrhea (p < 0.001), and vertigo (p = 0.006). Two girls also experienced new-onset unilateral sensorineural hearing loss following SARS-CoV-2 infection. Children with a known history of unilateral hearing loss did not have a higher prevalence of audio-vestibular symptoms than children with normal hearing. CONCLUSIONS: Our results suggest that the COVID-19 vaccine is safe and can be recommended for children with unilateral hearing loss without fear of possible audio-vestibular sequelae.

Sudden hearing loss and early hyperbaric oxygen therapy: A preliminary study.

Purpose: Sudden sensorineural hearing loss (SSNHL) is a time-sensitive urgent condition. The aim of this study was to evaluate the frequency of hearing improvement in patients with idiopathic SSNHL who only received hyperbaric oxygen (HBO2) therapy within three days of symptom onset, instead of conventional corticosteroid treatment. Methods: The medical charts of patients who experienced SSNHL between January 1, 2012, and December 31, 2021, were reviewed. The present study included all adult patients who were diagnosed with idiopathic SSNHL and started HBO2 therapy within 72 hours of symptom onset. These subjects did not take corticosteroids due to contraindications or because they were concerned about possible side effects. The HBO2 therapy protocol consisted of at least 10 sessions of 85 minutes each with pure oxygen inhalation at 2.5 atmospheres absolute pressure. Results: Overall, 49 subjects (26 males and 23 females) met the inclusion criteria, with a mean age of 47 (± 20.4) years. The mean initial hearing threshold was 69.8 dB (±18.0). After HBO2 therapy, complete hearing recovery was observed in 35 patients (71.4%), and the mean hearing threshold improved significantly (p≺0.001) to 31.4 dB (±24.5). In patients with complete hearing recovery, no significant differences were found between males and females (p=0.79), right and left ears (p=0.72) or initial grades of hearing loss (p=0.90). Conclusion: This study suggests that, in the absence of the confounding effect of concurrent steroid therapy, starting HBO2 therapy within three days of symptom onset could have a positive impact on patients with idiopathic SSNHL.

Primary Ciliary Dyskinesia: The Impact of Taste Receptor (TAS2R38) Gene Polymorphisms on Disease Outcome and Severity.

BACKGROUND: Primary ciliary dyskinesia (PCD) is a rare genetic disease leading to recurrent respiratory infections of upper and lower airways. Chronic rhinosinusitis (CRS) and bronchiectasis are very common in PCD patients. Recently, it has been shown the presence of taste receptors in respiratory tract and the possible involvement of bitter taste receptor TAS2R38 gene in susceptibility to respiratory infections and rhinosinusitis. OBJECTIVE: Aim of this study was to evaluate the frequency of TAS2R38 polymorphisms in PCD patients and their possible correlations with clinical outcomes of the disease. METHODS: Genetic and phenotypic data of 35 PCD patients were collected. Clinical evaluation included neonatal respiratory distress (NRD) at birth, presence of situs inversus, CRS, and bronchiectasis. We also measured the number of respiratory infections per year and the relevant pathogens, Lund-Mackay score, FEV1, and modified Bhalla score. With regard to genetics data, 3 polymorphisms (rs1726866, rs713598, and rs10246939) within TAS2R38 gene were analyzed and the patients were classified as PAV/PAV, PAV/AVI, and AVI/AVI. RESULTS: A significant difference in the distribution of TAS2R38 haplotype between patients with and without NRD emerged (p value = 0.01). A lower percentage of PAV/PAV individuals showed frequent respiratory exacerbations (≥2/year) (p value = 0.04) compared to those with AVI/AVI and AVI/PAV haplotypes. Moreover, no patients homozygous for PAV/PAV haplotype presented chronic colonization by Pseudomonas aeruginosa, thus supporting the possible role of TAS2R38 gene in susceptibility to respiratory infections. CONCLUSIONS: Here, we report, for the first time, a possible association of TAS2R38 polymorphisms with PCD phenotype.

Vestibular and audiological findings in the Alport syndrome.

Alport syndrome (AS) is caused by mutations in collagen IV, which is widespread in the basement membranes of many organs, including the kidneys, eyes, and ears. Whereas the effects of collagen IV changes in the cochlea are well known, no changes have been described in the posterior labyrinth. The aim of this study was to investigate both the auditory and the vestibular function of a group of individuals with AS. Seventeen patients, aged 9-52, underwent audiological tests including pure-tone and speech audiometry, immittance test and otoacoustic emissions and vestibular tests including video head impulse test, rotatory test, and vestibular evoked myogenic potentials. Hearing loss affected 25% of the males and 27.3% of the females with X-linked AS. It was sensorineural with a cochlear localization and a variable severity. 50% of the males and 45.4% of the females had a hearing impairment in the high-frequency range. Otoacoustic emissions were absent in about one-third of the individuals. A peripheral vestibular dysfunction was present in 75% of the males and 45.4% of the females, with no complaints of vertigo or dizziness. The vestibular impairment was compensated and the vestibulo-ocular reflex asymmetry was more evident in rotatory tests carried out at lower than higher speeds; a vestibular hypofunction was present in all hearing impaired ears although it was also found in subjects with normal hearing. A posterior labyrinth injury should be hypothesized in AS even when the patient does not manifest hearing disorders or evident signs of renal failure.

Diagnosis of congenital CMV infection via DBS samples testing and neonatal hearing screening: an observational study in Italy.

BACKGROUND: Congenital Cytomegalovirus (cCMV) is the most common cause of non-genetic hearing loss in childhood. A newborn hearing screening program (NHSP) is currently running in Italy, but no universal cCMV nor statewide hearing-targeted CMV screening programs have been implemented yet. This observational monocentric study was aimed at estimating the rate of cCMV infections identified by CMV-DNA analysis on Dried Blood Spots (DBS) samples in deaf children identified via NHSP in Northern Italy in the period spanning from 2014 to 2018. METHODS: Children with a confirmed diagnosis of deafness and investigated for CMV-DNA by nucleic acid extraction and in-house polymerase-chain reaction (PCR) on stored newborns screening cards (DBS-test) were included in this study. Deafness was defined by a hearing threshold ≥20 decibel (dB HL) by Auditory Brainstem Responses (ABR); all investigated DBS samples were collected within 3 days of life. RESULTS: Overall, 82 children were included (median age: 3.4 months; lower-upper quartiles: 2-5.3 months; males: 60.9%). Most of them (70.7%) presented bilateral hearing loss with a symmetrical pattern in 79.3% of the cases. ABR thresholds were ≥ 70 dB HL (severe/profound deafness) in 46.5% of children. Among all tested children, 6.1% resulted positive for cCMV. The rate of severe/profound deafness was statistically higher in children with cCMV infection. CONCLUSIONS: The addition of DBS-test to the NHSP allowed the identification, in their first months of life, of a cCMV infection in 6.1% of children who had failed NHS. The introduction of a targeted CMV screening strategy could help clinicians in the differential diagnosis and in the babies' management. DBS samples can be considered a "universal newborns biobank": their storage site and duration should be the subject of political decision-making.

Effects of Tinnitus Retraining Therapy with Different Colours of Sound.

BACKGROUND: In Tinnitus Retraining Therapy (TRT) sound stimulation is conventionally performed with low-level broadband sound generators; since the patient has to receive it for many hours in a day, it is important that the sound is tolerable and agreeable to the patient. A clinical trial was undertaken to evaluate the effect of different colour sound generators on tinnitus. The colour of a sound refers to the power spectrum of the signal. The sound generators used in this study provide the option to choose the preferred or most acceptable sound among white, red and pink noise. METHODS AND FINDINGS: Changes in Tinnitus Handicap Inventory and Numeric Rating Scales were measured in 20 patients after 3 and 6 months following the fitting of ear-level multi-colour sound generators. The outcomes were compared to a similar group of 20 participants receiving the same management except through conventional white noise sound generators. Significant improvements were obtained in both groups following 3 and 6 months after fitting. No significant difference was found between the two groups using one or the other type of sound. Two thirds of the patient preferred white noise, making it the most appealing amongst the options. The rest of the patients indicated red noise as the preferred sound given that it reminded them of soothing noises like shower or rainfall. No one chose pink noise. CONCLUSIONS: TRT with different colour sound generators is effective in reducing the discomfort caused by tinnitus in normal hearing patients. Enabling the patients to choose their preferred sound after short trial periods achieved higher patient satisfaction. This practice could help tailor individualized treatment for each patient.

First independent replication of the involvement of LARS2 in Perrault syndrome by whole-exome sequencing of an Italian family.

Perrault syndrome (MIM #233400) is a rare autosomal recessive disorder characterized by ovarian dysgenesis and primary ovarian insufficiency in females, and progressive hearing loss in both genders. Recently, mutations in five genes (HSD17B4, HARS2, CLPP, LARS2 and C10ORF2) were found to be responsible for Perrault syndrome, although they do not account for all cases of this genetically heterogeneous condition. We used whole-exome sequencing to identify pathogenic variants responsible for Perrault syndrome in an Italian pedigree with two affected siblings. Both patients were compound heterozygous for two novel missense variants within the mitochondrial leucyl-tRNA synthetase (LARS2): NM_015340.3:c.899C>T(p.Thr300Met) and c.1912G>A(p.Glu638Lys). Both variants cosegregated with the phenotype in the family. p.Thr300 and p.Glu638 are evolutionarily conserved residues, and are located, respectively, within the editing domain and immediately before the catalytically important KMSKS motif. Homology modeling using as template the E. coli leucyl-tRNA synthetase provided further insights on the possible pathogenic effects of the identified variants. This represents the first independent replication of the involvement of LARS2 mutations in Perrault syndrome, contributing valuable information for the further understanding of this disease.

A novel mutation within the MIR96 gene causes non-syndromic inherited hearing loss in an Italian family by altering pre-miRNA processing.

The miR-96, miR-182 and miR-183 microRNA (miRNA) family is essential for differentiation and function of the vertebrate inner ear. Recently, point mutations within the seed region of miR-96 were reported in two Spanish families with autosomal dominant non-syndromic sensorineural hearing loss (NSHL) and in a mouse model of NSHL. We screened 882 NSHL patients and 836 normal-hearing Italian controls and identified one putative novel mutation within the miR-96 gene in a family with autosomal dominant NSHL. Although located outside the mature miR-96 sequence, the detected variant replaces a highly conserved nucleotide within the companion miR-96*, and is predicted to reduce the stability of the pre-miRNA hairpin. To evaluate the effect of the detected mutation on miR-96/mir-96* biogenesis, we investigated the maturation of miR-96 by transient expression in mammalian cells, followed by real-time reverse-transcription polymerase chain reaction (PCR). We found that both miR-96 and miR-96* levels were significantly reduced in the mutant, whereas the precursor levels were unaffected. Moreover, miR-96 and miR-96* expression levels could be restored by a compensatory mutation that reconstitutes the secondary structure of the pre-miR-96 hairpin, demonstrating that the mutation hinders precursor processing, probably interfering with Dicer cleavage. Finally, even though the mature miR-96 sequence is not altered, we demonstrated that the identified mutation significantly impacts on miR-96 regulation of selected targets. In conclusion, we provide further evidence of the involvement of miR-96 mutations in human deafness and demonstrate that a quantitative defect of this miRNA may contribute to NSHL.

Effects on hearing after long-term use of iron chelators in beta-thalassemia: Over twenty years of longitudinal follow-up.

OBJECTIVE: The role of iron chelation in causing hearing loss (HL) is still unclear. The present study assessed the prevalence of HL among transfusion-dependent thalassemia (TDT) patients who underwent audiological follow-up over a 20-year period. METHODS: We retrospectively analyzed clinical records and audiological tests from January 1990 (T0) to December 2022 (T22) of a group of TDT patients who received iron chelation therapy with deferoxamine (DFO), deferiprone (DFP) or deferasirox (DFX), in monotherapy or as part of combination therapy. RESULTS: A total of 42 adult TDT patients (18 male, 24 female; age range: 41-55 years; mean age: 49.2 ± 3.7 years) were included in the study. At the T22 assessment, the overall prevalence of sensorineural HL was 23.8 % (10/42). When patients were stratified into two groups, with and without ototoxicity, no differences were observed for sex, age, BMI, creatinine level, pre-transfusional hemoglobin, start of transfusions, cardiac or hepatic T2 MRI; only ferritin serum values and duration of chelation were significantly higher (p = 0.02 and p = 0.01, respectively) in patients with hearing impairment in comparison to those with normal hearing. CONCLUSION: This study with long-term follow-up suggests that iron chelation therapy might induce ototoxicity; therefore, a long and accurate audiological follow-up should be performed in TDT patients.

Unilateral Sensorineural Hearing Loss in Children: Etiology, Audiological Characteristics, and Treatment.

The aim of this study was to evaluate audiological characteristics and parents' opinions on hearing device use in children with unilateral sensorineural hearing loss (USNHL) who attended a tertiary-level audiologic center. The medical charts of 70 children aged 6 to 12 years with USNHL were reviewed. In 51.4% of cases, the children were diagnosed with USNHL after the age of 2 years. The main causes of USNHL were congenital cytomegalovirus infection (21.4%) and unilateral cochlear nerve hypoplasia (12.9%). The percentage of patients wearing a hearing device was 45.7% (32/70); of these, 28 (87.5%) wore a conventional hearing aid, 2 (6.3%) a CROS device, and 2 (6.3%) a cochlear implant. Regarding the choice to use a hearing device, no significant differences were found between the subcategories of hearing loss degree (p = 0.55) and audiometric configuration (p = 0.54). Most parents of children with mild-to-severe USNHL observed improved attention (90.9%), and reduced fatigue and restlessness (86.4%) using the hearing aid. These children performed significantly better on all audiological tests (speech perception in quiet and in noise conditions, and sound localization) while wearing the hearing aid (p < 0.001). More efforts should be made to raise awareness among professionals and parents about the negative consequences of uncorrected USNHL.

Sudden Sensorineural Hearing Loss in Patients Aged from 15 to 40 Years.

Objectives: The purpose of this study was to investigate the hearing characteristics and causes of sudden sensorineural hearing loss (SSNHL) in patients aged from 15 to 40 years, focusing on audiological outcomes one year after the diagnosis. Methods: The medical records of individuals with SSNHL who were referred to our tertiary-level audiologic center were reviewed. All patients had undergone comprehensive diagnostic evaluations, including high-resolution 3D-FLAIR delayed magnetic resonance imaging (MRI), cone beam computed tomography (CBCT), and screening for coagulation, infectious, and autoimmune diseases. Results: Overall, 56 patients (mean age 28.1 ± 7.6 years) were included in the study. The hearing threshold in the affected ear improved significantly from 56.0 ± 18.0 dB at the diagnosis to 46.9 ± 22.3 dB after one year (p = 0.02). The degree of hearing loss, audiometric configurations, hearing improvements, and adherence to hearing treatments showed considerable variability among patients. Aural fullness, tinnitus, and hyperacusis were the predominant symptoms associated with SSNHL, and their prevalence decreased significantly over time. The diagnostic protocol led to the identification of the specific cause of SSNHL in 75% (42/56) of patients. The known etiology was found to be otological (39.3%), infectious (21.4%), autoimmune (7.1%), vascular (5.4%), or neoplastic (1.8%). In particular, Menière's disease (n = 12), isolated cochlear endolymphatic hydrops (n = 6), HSV-1 (n = 5), and EBV (n = 4) infections were the most frequent causes of SSNHL. Conclusions: The identification of the specific etiology of SSNHL may facilitate a more personalized approach to management and treatment.

Otitis Media With Effusion After the COVID-19 Pandemic: Return to the Past and New Lessons.

OBJECTIVE: To assess the prevalence of otitis media with effusion (OME) among children who attended a tertiary level audiologic center 2 and 3 years after the COVID-19 lockdown, and to determine the impact of temporary interruption of day care center attendance on chronic OME. STUDY DESIGN: Retrospective study. SETTING: Tertiary level referral audiologic center. METHODS: We assessed the prevalence of OME among children aged 6 months to 12 years in 3 different periods (May-June 2022, January-February 2023, and May-June 2023) and compared the results with those of the corresponding periods before the COVID-19 lockdown. We also compared the disease resolution rates between a subgroup of children with chronic OME who interrupted day care center attendance for a 2-month period (Subgroup A) and a similar subgroup who continued attending day care centers (Subgroup B). RESULTS: The prevalence of OME was 38.5% (138/358) in May-June 2022, 51.9% (193/372) in January-February 2023, and 40.9% (149/364) in May-June 2023. No significant prevalence differences were observed between the periods May-June 2019, May-June 2022, and May-June 2023 (P = .78), and between the periods January-February 2020 and January-February 2023 (P = .93). At the May-June 2023 assessment, the children belonging to Subgroup A presented a greater rate of disease resolution (85.7%, 18/21) than the children belonging to Subgroup B (32%, 8/25, P < .001). CONCLUSION: This study suggests that the prevalence of OME has returned to prelockdown levels, and that interrupting day care center attendance for a 2-month period could be effective in resolving most cases of chronic OME.

Public awareness of ear and hearing management as measured using a specific questionnaire.

Public awareness of audiological issues has never been measured in the general public even if the World Health Organization (WHO) has detected a common urgent need for action to prevent and manage ear diseases and hearing loss. The aim of this study was to measure urban community citizens' awareness of managing and preventing ear disease and hearing loss using a specific questionnaire. A questionnaire was formulated on the basis of WHO material concerning the major specific audiological issues and attitudes, focusing in particular on four domains: (1) knowledge of infant hearing loss, (2) correct management of the ears including cleaning and treating, (3) focus on the effect of overexposure to loud sounds and noise, (4) underestimated ear symptoms leading to diagnostic delay. 254 volunteers were enrolled in this cross-sectional study by a team of medical doctors and audiologists stationed in a mobile unit that visited different areas of Milan, Italy. More than 80% of correct responses were given to almost all of the statements by the interviewees, although certain important knowledge was found to be lacking. The proposed audiological questionnaire seems to be a suitable tool to evaluate the public awareness of ear and hearing management. The results showed a need for continued development of comprehensive hearing conservation programs, focused on hearing aid management and early infant hearing loss identification as well as noise exposure.

Chronic Rhinosinusitis: T2r38 Genotyping and Nasal Cytology in Primary Ciliary Dyskinesia.

OBJECTIVES: Chronic rhinosinusitis (CRS) is a major hallmark of primary ciliary dyskinesia (PCD). We investigated the possible correlation between some severity markers of CRS and several clinical features of the disease. We further studied the bitter taste receptor TAS2R38 polymorphisms to identify the genotypes associated with more severe disease. METHODS: We included 39 adult PCD patients with (CRSwNP) and without nasal polyposis (CRSsNP); a sample for nasal cytology was obtained and clinical cytological grading (CCG) was determined. The SNOT-22 and Lund-Mackay scores were recorded. A sample of DNA was extracted from peripheral blood to investigate TAS2R38 polymorphisms. RESULTS: CRSwNP patients had features of more severe disease: indeed, they had statistically significantly higher frequency of previous sinus surgery, higher SNOT-22, LM scores, and CCG than CRSsNP patients. Upon genotyping of TAS2R38 polymorphisms, we observed that the AVI-AVI genotype, associated to homozygous nonfunctional bitter TAS2R38 receptor, was more prevalent among CRSwNP (100%) than in CRSsNP patients (0%); furthermore, AVI-AVI subjects showed statistically significantly worse SNOT-22 and CCG scores than PAV-PAV and PAV-AVI subjects. The group of AVI-AVI patients also had more frequent respiratory exacerbations, Gram-negative infections, and Pseudomonas aeruginosa colonization than PAV-PAV and PAV-AVI patients. CONCLUSION: Our findings indicate for the first time that PCD patients with CRSwNP display a more severe disease than those with CRSsNP. Genotyping of TAS2R38 polymorphisms demonstrated that in PCD patients, the AVI-AVI genotype is strikingly more prevalent among CRSwNP than in CRSsNP, while the PAV-PAV genotype might be protective against Gram-negative infections and respiratory exacerbations. LEVEL OF EVIDENCE: 3 Laryngoscope, 133:248-254, 2023.

Congenital Cytomegalovirus and Hearing Loss: The State of the Art.

In developed countries, congenital cytomegalovirus (cCMV) infection is the most common congenital viral infection, representing the leading non-genetic cause of sensorineural hearing loss (HL). Diagnosis of cCMV infection can be performed by detection of CMV DNA in urine or saliva within 2-3 weeks after birth, or later in dried blood samples on the Guthrie card. Currently, there are many controversies regarding the preventive, diagnostic, and therapeutic approaches to cCMV infection. HL secondary to cCMV is highly variable in onset, side, degree, audiometric configuration, and threshold changes over time. Therefore, it is of paramount importance to perform a long and thorough audiological follow-up in children with cCMV infection to ensure early identification and prompt treatment of progressive and/or late-onset HL. Early cochlear implantation appears to be a valid solution not only for children with bilateral profound HL, but also for those with single-sided deafness, improving localization ability and understanding speech in noisy environments. Moreover, the decision to apply a unilateral cochlear implant in children with cCMV is strengthened by the non-negligible possibility of hearing deterioration of the contralateral ear over time.

Hearing outcomes in children with congenital cytomegalovirus infection: From management controversies to lack of parents' knowledge.

OBJECTIVES: Congenital cytomegalovirus (cCMV) is the leading nongenetic cause of sensorineural hearing loss (HL). However, there are no universally accepted approaches to diagnosis, follow-up and treatment. The aim of this study was to evaluate the main characteristics of cCMV-infected children, focusing on their management and long-term hearing outcomes. METHODS: This retrospective study included all children with cCMV infection who were referred to a third-level referral audiologic center for a 6-year hearing follow-up. The main information collected from the medical records included gestational age, birth weight, trimester of maternal seroconversion, hearing status at birth and after 6 years, hearing fluctuations, treatment with oral valganciclovir (within the first month of life and for 6 months), use of hearing devices, presence of speech-language delay, motor delay, cognitive delay and balance disorders, awareness of cCMV among parents, and parents' engagement in behaviors that could increase the risk of CMV infection during pregnancy. RESULTS: A total of 141 children with cCMV infection (72 males and 69 females; mean gestational age: 37+3 weeks; mean birth weight: 2893 g) were assessed. Overall, 48 children (34.0%) had a diagnosis of speech-language delay, 32 (22.7%) of sensorineural HL (59.4% bilaterally; 50% of profound degree), 18 (12.8%) of motor delay, 16 (11.3%) of balance disorders, and 6 (4.3%) of cognitive delay. Among children with HL, 8 (25.0%) were fitted with hearing aids (5 unilaterally and 3 bilaterally), and 5 (15.6%) had undergone cochlear implantation (1 unilaterally and 4 bilaterally), while a bimodal hearing solution was adopted for 2 (6.3%) patients. Compared to children with asymptomatic cCMV infection, symptomatic children had a higher prevalence of neurological and auditory sequelae (P < 0.01) and bilateral (P = 0.003) and severe-to-profound HL (P = 0.004). Overall, 23 children (16.3%) received oral valganciclovir, and only one of them experienced hearing deterioration. Only 14.9% of mothers and 5% of fathers were aware that cCMV could cause progressive or late-onset HL, and 87.9% of parents (248/282) had engaged in behaviors that increased the risk of CMV infection during pregnancy. CONCLUSION: This study confirmed the importance of performing a long audiological follow-up in children diagnosed with cCMV infection due to the possible late-onset, progressive and fluctuating nature of HL. Moreover, the study highlighted many current controversies in preventive (poor prenatal education), diagnostic (routine maternal serological screening) and therapeutic (valganciclovir administered to asymptomatic children) approaches to cCMV infection. More efforts should be made to improve prevention strategies and raise awareness of cCMV infection risks among the population.

In-depth genetic and molecular characterization of diaphanous related formin 2 (DIAPH2) and its role in the inner ear.

Diaphanous related formins are regulatory cytoskeletal protein involved in actin elongation and microtubule stabilization. In humans, defects in two of the three diaphanous genes (DIAPH1 and DIAPH3) have been associated with different types of hearing loss. Here, we investigate the role of the third member of the family, DIAPH2, in nonsyndromic hearing loss, prompted by the identification, by exome sequencing, of a predicted pathogenic missense variant in DIAPH2. This variant occurs at a conserved site and segregated with nonsyndromic X-linked hearing loss in an Italian family. Our immunohistochemical studies indicated that the mouse ortholog protein Diaph2 is expressed during development in the cochlea, specifically in the actin-rich stereocilia of the sensory outer hair cells. In-vitro studies showed a functional impairment of the mutant DIAPH2 protein upon RhoA-dependent activation. Finally, Diaph2 knock-out and knock-in mice were generated by CRISPR/Cas9 technology and auditory brainstem response measurements performed at 4, 8 and 14 weeks. However, no hearing impairment was detected. Our findings indicate that DIAPH2 may play a role in the inner ear; further studies are however needed to clarify the contribution of DIAPH2 to deafness.