Lack of Methylation Changes in GJB2 and RB1 Non-coding Regions of Cochlear Implant Patients with Sensorineural Hearing Loss.

Objective: Recent advances in epigenetic studies continue to reveal novel mechanisms of gene regulation and control, however little is known on the role of epigenetics in sensorineural hearing loss (SNHL) in humans. We aimed to investigate the methylation patterns of two regions, one in RB1 and another in GJB2 in Filipino patients with SNHL compared to hearing control individuals. Methods: We investigated an RB1 promoter region that was previously identified as differentially methylated in children with SNHL and lead exposure. Additionally, we investigated a sequence in an enhancer-like region within GJB2 that contains four CpGs in close proximity. Bisulfite conversion was performed on salivary DNA samples from 15 children with SNHL and 45 unrelated ethnically-matched individuals. We then performed methylation-specific real-time PCR analysis (qMSP) using TaqMan® probes to determine percentage methylation of the two regions. Results: Using qMSP, both our cases and controls had zero methylation at the targeted GJB2 and RB1 regions. Conclusion: Our study showed no changes in methylation at the selected CpG regions in RB1 and GJB2 in the two comparison groups with or without SNHL. This may be due to a lack of environmental exposures to these target regions. Other epigenetic marks may be present around these regions as well as those of other HL-associated genes.

Audiologic Measures in an Indigenous Community with A2ML1- and FUT2-Related Otitis Media.

Background: Many indigenous peoples are at elevated risk for otitis media, however there is limited information on hearing loss due to OM in these communities. An Indigenous Filipino community that has previously been described with an elevated prevalence of OM that is due to rare A2ML1 variants and a common FUT2 variant underwent additional phenological testing. In this study, we describe the audiologic profiles in A2ML1- and FUT2-related otitis media and the validity of otoscopy and genotyping for A2ML1 and FUT2 variants in screening for otitis media and hearing loss. Method: We analyzed A2ML1 and FUT2 genotypes together with demographic, otologic and audiologic data from tympanometry and hearing level assessments of 109 indigenous individuals. Results: We confirmed previous findings of a spectrum of nonsyndromic otitis media as associated with A2ML1 variants. A2ML1 and FUT2 variants were associated with high-frequency hearing loss at 4000 Hz. As expected, young age was associated with flat tympanograms, and eardrum perforations due to chronic otitis media were associated with severe-to-profound hearing loss across frequencies. Adding A2ML1 or FUT2 genotypes improved the validity of otoscopy as a screening test to rule out moderate-to-profound hearing loss. Conclusion: Continued multi-disciplinary management and audiologic follow-up using tympanometry and screening audiometry are needed to document and treat otitis media and prevent permanent hearing loss in the indigenous community.

Otologic and vestibular symptoms in COVID-19: A scoping review.

Background: Otologic and vestibular symptoms have been seen in patients confirmed to have COVID-19 disease. Further discussion of these symptoms may provide insight into short- and long-term management for these patients. Objective: The aim of this review was to describe the otologic and vestibular symptoms that present in patients with COVID-19. The primary outcomes of this review were onset, duration and clinical outcomes of these symptoms. Sources of Evidence: Pub Med, APAMed Central, Herdin, CINAHL, Scopus, Springer Link, ProQuest Coronavirus Research Database, and Google Scholar were searched for the articles to be included. Eligibility Criteria: Studies included were those involving adult patients diagnosed with COVID-19 who experienced hearing loss, ear pain, ear discharge, otitis media, vertigo, or tinnitus. Studies were eligible for inclusion if there was a description of the otologic dysfunction, specifically onset, duration, or clinical outcomes. Results: The majority of patients who experienced hearing loss (68%), tinnitus (88%), vertigo/dizziness (30%), ear pain (8%), and discharge (100%) did so within a month of experiencing the typical symptoms of COVID-19. A majority also experienced complete resolution of their symptoms within 2 weeks. Standard treatment for COVID-19 was usually provided but when specific diagnoses are made for these symptoms (e.g., sudden sensorineural hearing loss, otitis media, vestibular neuritis), they are treated in the same manner as one would for non-COVID-19 cases, in addition to the management for COVID-19. In certain cases, there may be a need for additional work-up to rule out other causes. Conclusions: Otologic and vestibular symptoms were present in COVID-19 patients, majority as part of the systemic nature of the disease. The onset, duration, and course were consistent with the natural history of a systemic viral infection. COVID-19 should be considered in any patient with a new-onset hearing loss, tinnitus, or vertigo/dizziness, even in the absence of infectious or respiratory symptoms.

Identification of Novel Candidate Genes and Variants for Hearing Loss and Temporal Bone Anomalies.

Background: Hearing loss remains an important global health problem that is potentially addressed through early identification of a genetic etiology, which helps to predict outcomes of hearing rehabilitation such as cochlear implantation and also to mitigate the long-term effects of comorbidities. The identification of variants for hearing loss and detailed descriptions of clinical phenotypes in patients from various populations are needed to improve the utility of clinical genetic screening for hearing loss. Methods: Clinical and exome data from 15 children with hearing loss were reviewed. Standard tools for annotating variants were used and rare, putatively deleterious variants were selected from the exome data. Results: In 15 children, 21 rare damaging variants in 17 genes were identified, including: 14 known hearing loss or neurodevelopmental genes, 11 of which had novel variants; and three candidate genes IST1, CBLN3 and GDPD5, two of which were identified in children with both hearing loss and enlarged vestibular aqueducts. Patients with variants within IST1 and MYO18B had poorer outcomes after cochlear implantation. Conclusion: Our findings highlight the importance of identifying novel variants and genes in ethnic groups that are understudied for hearing loss.

Otitis media susceptibility and shifts in the head and neck microbiome due to SPINK5 variants.

BACKGROUND: Otitis media (OM) susceptibility has significant heritability; however, the role of rare variants in OM is mostly unknown. Our goal is to identify novel rare variants that confer OM susceptibility. METHODS: We performed exome and Sanger sequencing of >1000 DNA samples from 551 multiethnic families with OM and unrelated individuals, RNA-sequencing and microbiome sequencing and analyses of swabs from the outer ear, middle ear, nasopharynx and oral cavity. We also examined protein localisation and gene expression in infected and healthy middle ear tissues. RESULTS: A large, intermarried pedigree that includes 81 OM-affected and 53 unaffected individuals cosegregates two known rare A2ML1 variants, a common FUT2 variant and a rare, novel pathogenic variant c.1682A>G (p.Glu561Gly) within SPINK5 (LOD=4.09). Carriage of the SPINK5 missense variant resulted in increased relative abundance of Microbacteriaceae in the middle ear, along with occurrence of Microbacteriaceae in the outer ear and oral cavity but not the nasopharynx. Eight additional novel SPINK5 variants were identified in 12 families and individuals with OM. A role for SPINK5 in OM susceptibility is further supported by lower RNA counts in variant carriers, strong SPINK5 localisation in outer ear skin, faint localisation to middle ear mucosa and eardrum and increased SPINK5 expression in human cholesteatoma. CONCLUSION: SPINK5 variants confer susceptibility to non-syndromic OM. These variants potentially contribute to middle ear pathology through breakdown of mucosal and epithelial barriers, immunodeficiency such as poor vaccination response, alteration of head and neck microbiota and facilitation of entry of opportunistic pathogens into the middle ear.

A2ML1 and otitis media: novel variants, differential expression, and relevant pathways.

A genetic basis for otitis media is established, however, the role of rare variants in disease etiology is largely unknown. Previously a duplication variant within A2ML1 was identified as a significant risk factor for otitis media in an indigenous Filipino population and in US children. In this report exome and Sanger sequencing was performed using DNA samples from the indigenous Filipino population, Filipino cochlear implantees, US probands, Finnish, and Pakistani families with otitis media. Sixteen novel, damaging A2ML1 variants identified in otitis media patients were rare or low-frequency in population-matched controls. In the indigenous population, both gingivitis and A2ML1 variants including the known duplication variant and the novel splice variant c.4061 + 1 G>C were independently associated with otitis media. Sequencing of salivary RNA samples from indigenous Filipinos demonstrated lower A2ML1 expression according to the carriage of A2ML1 variants. Sequencing of additional salivary RNA samples from US patients with otitis media revealed differentially expressed genes that are highly correlated with A2ML1 expression levels. In particular, RND3 is upregulated in both A2ML1 variant carriers and high-A2ML1 expressors. These findings support a role for A2ML1 in keratinocyte differentiation within the middle ear as part of otitis media pathology and the potential application of ROCK inhibition in otitis media.

FUT2 Variants Confer Susceptibility to Familial Otitis Media.

Non-secretor status due to homozygosity for the common FUT2 variant c.461G>A (p.Trp154∗) is associated with either risk for autoimmune diseases or protection against viral diarrhea and HIV. We determined the role of FUT2 in otitis media susceptibility by obtaining DNA samples from 609 multi-ethnic families and simplex case subjects with otitis media. Exome and Sanger sequencing, linkage analysis, and Fisher exact and transmission disequilibrium tests (TDT) were performed. The common FUT2 c.604C>T (p.Arg202∗) variant co-segregates with otitis media in a Filipino pedigree (LOD = 4.0). Additionally, a rare variant, c.412C>T (p.Arg138Cys), is associated with recurrent/chronic otitis media in European-American children (p = 1.2 × 10-5) and US trios (TDT p = 0.01). The c.461G>A (p.Trp154∗) variant was also over-transmitted in US trios (TDT p = 0.01) and was associated with shifts in middle ear microbiota composition (PERMANOVA p < 10-7) and increased biodiversity. When all missense and nonsense variants identified in multi-ethnic US trios with CADD > 20 were combined, FUT2 variants were over-transmitted in trios (TDT p = 0.001). Fut2 is transiently upregulated in mouse middle ear after inoculation with non-typeable Haemophilus influenzae. Four FUT2 variants-namely p.Ala104Val, p.Arg138Cys, p.Trp154∗, and p.Arg202∗-reduced A antigen in mutant-transfected COS-7 cells, while the nonsense variants also reduced FUT2 protein levels. Common and rare FUT2 variants confer susceptibility to otitis media, likely by modifying the middle ear microbiome through regulation of A antigen levels in epithelial cells. Our families demonstrate marked intra-familial genetic heterogeneity, suggesting that multiple combinations of common and rare variants plus environmental factors influence the individual otitis media phenotype as a complex trait.

Prevalence and reasons for non-follow-up of newborns with "refer" results on initial hearing screening

OBJECTIVE: To determine the prevalence rate of follow-up among infants who had a "refer" result on initial newborn hearing screening and to identify reasons for default by parents or guardians.METHODS:Design: Cross-Sectional StudySetting: Tertiary National University HospitalParticipants: 79 parents or guardians whose newborns obtained a "refer" result on initial hearing screening were interviewed over the phone.RESULTS: Among those babies who had a "refer" result on initial hearing screening, 51% followed up for repeat testing. The most common reasons for non-follow up by parents or guardians include being busy, distance from the hospital and baby's health condition.CONCLUSIONS: The follow-up rate in this study is higher compared to previous figures (27%), but is still below target. The reasons for non-follow-up obtained suggest problems may exist on all levels of the healthcare system. Appropriate solutions to address these problems should be explored.

Middle ear microbiome differences in indigenous Filipinos with chronic otitis media due to a duplication in the A2ML1 gene.

BACKGROUND: Previously rare A2ML1 variants were identified to confer otitis media susceptibility in an indigenous Filipino community and in otitis-prone US children. The goal of this study is to describe differences in the middle ear microbiome between carriers and non-carriers of an A2ML1 duplication variant that increases risk for chronic otitis media among indigenous Filipinos with poor health care access. METHODS: Ear swabs were obtained from 16 indigenous Filipino individuals with chronic otitis media, of whom 11 carry the A2ML1 duplication variant. Ear swabs were submitted for 16S rRNA gene sequencing. RESULTS: Genotype-based differences in microbial richness, structure, and composition were identified, but were not statistically significant. Taxonomic analysis revealed that the relative abundance of the phyla Fusobacteria and Bacteroidetes, and genus Fusobacterium were nominally increased in carriers compared to non-carriers, but were non-significant after correction for multiple testing. We also detected rare bacteria including Oligella that was reported only once in the middle ear. CONCLUSIONS: These findings suggest that A2ML1-related otitis media susceptibility may be mediated by changes in the middle ear microbiome. Knowledge of middle ear microbial profiles according to genetic background can be potentially useful for therapeutic and prophylactic interventions for otitis media and can guide public health interventions towards decreasing otitis media prevalence within the indigenous Filipino community.

Genetic and Environmental Determinants of Otitis Media in an Indigenous Filipino Population.

OBJECTIVE: To identify genetic and environmental risk factors for otitis media in an indigenous Filipino population. STUDY DESIGN: Cross-sectional study. SETTING: Indigenous Filipino community. SUBJECTS AND METHODS: Clinical history and information on breastfeeding, tobacco smoke exposure, and swimming were obtained from community members. Heads of households were interviewed for family history and personal beliefs on ear health. Height and weight were measured. Otoscopic findings were described for the presence and character of perforation or discharge. An A2ML1 duplication variant that confers otitis media susceptibility was Sanger sequenced in all DNA samples. Co-occurrence of middle ear bacteria detected by 16S rRNA gene sequencing was determined according to A2ML1 genotype and social cluster. RESULTS: The indigenous Filipino population has a ~50% prevalence of otitis media. Young age was associated with otitis media (4 age strata; P = .004); however, age was nonsignificant as a bistratal or continuous variable. There was no association between otitis media and sex, body mass index, breastfeeding, tobacco exposure, or deep swimming. In multivariate analyses, A2ML1 genotype is the strongest predictor of otitis media, with an odds ratio of 3.7 (95% confidence interval: 1.3-10.8; P = .005). When otitis media diagnoses were plotted across ages, otitis media was observed within the first year of life, and chronic otitis media persisted up to adulthood, particularly in A2ML1-variant carriers. CONCLUSION: Among indigenous Filipinos, A2ML1 genotype is the primary risk factor for otitis media and main determinant of disease progression, although age, the middle ear microbiome, and social clusters might modulate the effect of the A2ML1 genotype.

Prevalence of sensorineural hearing loss and its association with glycemic control in Filipino patients with diabetes at the Philippine General Hospital / Journal of the ASEAN Federation of Endocrine Societies

@#<p style="text-align: justify;"><strong>BACKGROUND:</strong> Sensorineural hearing loss (SNHL) is a form of diabetic neuropathy. Its prevalence rate varies from 21.7-73.3% among different populations. The association of this complication with long-term glycemic control has not been described extensively.<br /><strong>OBJECTIVES:</strong> The study aims to determine the prevalence of SNHL in Filipino patients with diabetes consulting in a tertiary hospital; and to determine the association of SNHL with the degree of blood sugar control as measured by the mean hemoglobin bA1c (HbA1c) for the last five years.<br /><strong>METHODOLOGY</strong>: A cross-sectional study of 128 patients in a tertiary hospital was done. Patients were recruited via stratified random sampling with the different clinics as the stratifying variable. They underwent physical examination and pure tone audiometry (PTA) to detect presence of SNHL and presence of distal peripheral neuropathy. Chart review was done to gather the HbA1c levels for the last five years, as well as data on the presence of retinopathy and nephropathy. The average HbA1c levels, and other clinical and demographic factors and their association with SNHL were analyzed using logistic regression.<br /><strong>RESULTS:</strong> The prevalence of SNHL among patients with diabetes is 45.31%. Glycemic control does not seem to be associated with SNHL (p value 0.451, OR 1.447). Age was found to be significantly associated with SNHL (p value=0.046, OR=1.035). Among patients age 60 years old and below, retinopathy was significantly associated with SNHL (p value 0.023, OR=3.564). Multivariate analysis did not show any significant predictor for SNHL. There was no observed difference in the proportion of patients with SNHL among males (48.94%) compared to females (43.21%), p value of 0.530. A more advanced age is associated with SNHL among males (p value 0.024, OR=1.095) and a family history of hearing loss is an independent predictor of SNHL (p value 0.047, OR=1.088).<br /><strong>CONCLUSION:</strong> There is a high prevalence rate of SNHL among Filipino patients with diabetes. SNHL does not seem to be associated with glycemic control. Screening for SNHL maybe warranted for patients with diabetes due to its high prevalence rate regardless of glycemic control. Hearing care, focusing on prevention of hearing loss, should be advocated for patients with diabetes mellitus</p>

Rare A2ML1 variants confer susceptibility to otitis media.

A duplication variant within the middle ear-specific gene A2ML1 cosegregates with otitis media in an indigenous Filipino pedigree (LOD score = 7.5 at reduced penetrance) and lies within a founder haplotype that is also shared by 3 otitis-prone European-American and Hispanic-American children but is absent in non-otitis-prone children and >62,000 next-generation sequences. We identified seven additional A2ML1 variants in six otitis-prone children. Collectively, our studies support a role for A2ML1 in the pathophysiology of otitis media.

The voice test for newborn hearing screening

OBJECTIVES. The goal of the study is to find a reasonable aIternative test that can be utilized in the Philippine setting to operationalize the Universal Newborn Hearing Screening Act. Thus the components of the Voice Test were studied. The objectives of the study are to determine: (1) which of the two words "Baah" and "Psst" is better for newborn hearing screening rocedure as far as their physical characteristics are concerned, ~) how do the two words "Baah" and Psst" differ between genders and distance from sound source, (3) to determine the proportion of the participants who could recite the words at intensity of 80db or louder. METHODS. Frequency characteristics and sound intensity differences of two words "Baah" and "Psst" were determined and ompared. RESULTS. The word "Baah" exhibited more favorable physical attributes over the word 'Psst" for purposes of being a screening tool for newborn hearing assessment. CONCLUSION. This study reports the results of an initial step in the search for an inexpensive, feasible, and valid tool for neonatal earing screening. Correlation studies with speech developmental milestones may eventually enhance the usefulness of the voice test.

The ubiquitous TB otitis media: A review of diagnosis and treatment outcomes

OBJECTIVE: The purpose of this review is to improve the detection of TB otitis media cases and its treatment outcome by describing the varied clinical presentations, discussing the importance, limitations and frontiers of possible diagnostic tests and illustrating the roles of medical and surgical interventions METHOD: A review of available literature was done. The search included published researches on TB Otitis Media and related articles on tuberculosis. RESULTS: The review included aspects of the clinical presentation, diagnostic considerations, and treatment options, both medical and surgical, of tuberculous otitis media. CONCLUSION: Tuberculous otitis media presents with a variety of clinical features so that a high index of suspicion is very important. Diagnostic examinations are available but are varied depending on the clinical presentation. Definitive treatment is mainly medical with anti- Koch's medications.

Auditory brainstem response latencies of infants and maternal eposure to environmental toxic product

OBJECTIVE: To explore the effects of pesticide exposure on the auditory system, specifically on hearing status based on auditory brainstem responses. METHODS: A cohort of pregnant women was identified in several communities in a rural area from April 2002 to February 2003 and followed up until delivery. Mother-infant dyads were assessed for exposure to pesticides. Maternal and fetal exposures to environmental toxic products were determined by measuring levels in maternal hair and blood, and infant cord blood, hair, and meconium, respectively. Hearing status was measured using otoacoustic emissions (OAE) and confirmed by diagnostic auditory brainstem responses (ABR) measured at 80, 60, and 40 decibels. Waves I, III, V were identified and absolute latencies measured, including inter-peak latencies from waves 11III, I-V, and III-V. Pesticide exposure was then correlated with latencies of Waves I, III, V, and interpeak latencies of waves I-III, IIV, and III-V. Hearing loss and pesticide exposures were correlated with Griffiths Mental Development Scores (GMDS). RESULTS: Significant delays in the ABR wave latencies were noted in the group with exposure to pesticides. Propoxur was the most common toxic product detected in infants and meconium the best substrate for its detection. There was a 1.4% risk of hearing loss with exposure to propoxur (RR=0.52 (0.12-2.30), p = 0.06), a 6.25% risk with cypermethrin exposure (RR= 4.53 (0.61133.64), P = 0.10) and 6.25% risk with pretilachlor exposure (3.13 (0.44-22.30), p = 0.07). Griffith's Mental Developmental Scale scores (GMDS- hearing and speech subscale and general quotient scores) were not significantly different between exposed and unexposed groups. However, three infants with positive exposures and hearing loss had below average, or low to average scores using this scale. CONCLUSION: Maternal exposure to environmental toxic products may affect the auditory pathway in infants at birth. Pregnant women should limit their exposure to such toxic products in order to avoid neurodevelopmental effects particularly on hearing because this is very important in the critical stage of language and speech development.

Training of nurses in ear examination and hearing screening in the school setting.

The objectives of this study were to determine the agreement between the ear examination findings of the otorhinolaryngologist (trainer) and the elementary school nurse (trainee) after training with the use of a penlight and to determine the mean sound pressure level (SPL) produced by school nurses as a standard parameter for hearing screening using a 512 tuning fork after training on tuning fork testing by the otorhinolaryngologist. Training workshops in ear examination using a penlight and hearing screening using a 512 tuning fork were conducted for school nurses. Data for assessment of ear examination skills and production of SPL were collected by questionnaire and observation of performance. Kappa statistics were used to assess agreement between trainees' and trainer's responses. Mean and standard deviation were determined for the assessment of the SPL produced. Results showed an excellent agreement between the school nurses' and otorhinolaryngologist's observations on ear examination. These included observations of the ear canal, visualization of the tympanic membrane and identification of unusual findings such as wax and discharge. The majority of nurses responded positively in terms of the ease and confidence in performance of the procedure. Regarding tuning fork testing, the nurses were able to produce significant SPL. The mean SPL produced by the nurses using a 512 tuning fork was 56.316 dB.