Progressive Hearing Loss Research Articles

49 Case Study: Cognitive Deficits Associated with Norrie Disease

Objective:Norrie disease is a rare, x-linked recessive genetic disorder associated with an NDP gene mutation. Males are predominantly affected. Typical symptoms include vision loss around the time of birth and progressive hearing loss. Cognitive and behavioral abnormalities also occur in 30-50% of individuals, including developmental delays, intellectual disability, cognitive regression, psychosis, and aggression. There is limited research, however, examining the neuropsychological deficits in adulthood resulting from Norrie disease, especially with neuropsychological data and in individuals without other neurological manifestations of the disease, such as seizures. Here, we present the neurocognitive profile of a patient with Norrie disease who presented for a cognitive evaluation in adulthood due to report of more recent memory decline.Participants and Methods:Mr. Smith is a Caucasian male in his mid-40's who previously underwent genetic testing and was subsequently diagnosed with Norrie disease. As a result of his diagnosis, he experienced complete vision loss since birth and bilateral hearing loss that began in childhood and gradually worsened in adolescence. Medical history was otherwise unremarkable. Developmental milestones were met on time. Historical intelligence testing conducted in elementary school revealed borderline on one intelligence test to high average performance on other intelligence tests. However, he was retained grades several times due to factors such as behavioral disruptions and academic difficulties. He had been employed as an assembly line worker for many years, but had not worked for 10 years prior to the neuropsychological evaluation. Emotionally, he had a longstanding history of anxiety and endorsed mild anxiety and depression at the time of the evaluation. The patient first noticed memory difficulties in adolescence then noticed further decline four years prior to the neuropsychological evaluation (around when he received a left-ear cochlear implant), which had remained stable since onset.Results:In the context of low average premorbid intellectual functioning, Mr. Smith's neurocognitive profile was notable for difficulties with alphanumeric set-shifting and abstract thinking, with otherwise preserved cognitive functioning. Weaknesses observed on testing may have represented longstanding weaknesses and did not rise to the level of a cognitive disorder. Affective distress was also suspected to have accounted for some of the cognitive lapses the patient reported experiencing with day-to-day functioning.Conclusions:The current poster aims to contribute to the limited body of literature examining neuropsychological deficits in adulthood resulting from Norrie disease. This is especially critical given that the long-term cognitive dysfunction of this disorder is relatively unknown and could negatively impact patients' quality of life over time.

Bilateral intracochlear schwannomas: histopathological confirmation and outcomes following tumour removal and cochlear implantation with lateral wall electrodes.

Intracochlear schwannomas (ICS) are very rare benign tumours of the inner ear. We present histopathological proof of the extremely rare bilateral occurrence of intracochlear schwannomas with negative blood genetic testing for neurofibromatosis type2 (NF2). Bilateral schwannomas are typically associated with the condition NF2 and this case is presumed to have either mosaicism for NF2 or sporadic development of bilateral tumours. For progressive bilateral tumour growth and associated profound hearing loss, surgical intervention via partial cochleoectomy, tumour removal, preservation of the modiolus, and simultaneous cochlear implantation with lateral wall electrode carrier with basal double electrode contacts was performed. The right side was operated on first with a14-month gap between each side. The hearing in aided speech recognition for consonant-nucleus-consonant (CNC) phonemes in quiet improved from 57% to 83% 12months after bilateral cochlear implantation (CI). Bilateral intracochlear schwannomas in non-NF2 patients are extremely rare but should be considered in cases of progressive bilateral hearing loss. Successful tumour removal and cochlear implantation utilizing alateral wall electrode is possible and can achieve good hearing outcomes.

A Retrospective Study of Clinical Profile of Patients with Autoimmune Inner Ear Disease.

Bilateral sensorineural hearing loss can be a very distressing symptom and can affect the efficiency of a person and one's quality of life. Conditions causing bilateral hearing loss are very few and autoimmune aetiology is one of them. Autoimmune ear disease is characterised by bilateral, mostly fluctuating audiovestibular symptoms and symptoms which respond to steroids. Diagnosis of AIED presents a unique challenge to clinicians due to the lack of standardized diagnostic criteria or reliable pathognomonic tests. The purpose of the study is to evaluate the patients who fit into criteria of autoimmune inner ear disease and understand the clinical features and response to medications for the same. A retrospective chart review of patients presenting with rapidly progressive bilateral hearing loss was done. The clinical presentation including detailed history and examination findings along with the blood investigation reports and audiograms were recorded in a tabular form. The study included 6 patients - 3 male and 3 female patients. Age of the patients at onset of hearing loss varied between 24-35 years. 3 of 6 patients presented with primary autoimmune ear disease and other 3 had hearing loss secondary to systemic autoimmune disease. All patients were treated with systemic steroids, but however showed a varied response. Patients with primary AIED were administered inner ear steroid therapy as well. AIED is thus a diagnosis of exclusion done with high index of suspicion. Patients with bilateral progressive sensorineural hearing loss should be evaluated for autoimmune etiology. Oral steroids with intratympanic steroids are currently the mainstay of treatment for AIED. Guarded prognosis of hearing improvement is noted in these patients. Hence, emphasis should be placed on early hearing rehabilitation for better quality of life.

Revision cochlear implant surgery in adults and children is a safe and effective technique: a retrospective single faculty study in Okayama University Hospital, Japan

Background Cochlear implant (CI) surgery is a safe surgical technique, although some patients require revision CI surgery. Aims/Objectives This study investigated the cause and underlying reason of revision CI surgery as well as hearing outcomes in a single institution. Patients and Methods This retrospective study evaluated patients who underwent CI surgery between April 2006 to March 2022 (n = 351). Sex, aetiology of hearing loss (HL), age and period from initial CI surgery to reimplantation, cause of revision, and related factors were examined. Results Twelve patients (8 males, 4 females) received CI reimplantation. The revision surgery rate was 2.59% (3.15% children, 1.69% adults); the period from initial surgery to reoperation was 8.60 ± 6.56 years for 9 children with congenital HL and 15.27 ± 5.72 years for 3 adults with progressive HL. Device failure was the most common cause (n = 8), followed by infections (n = 2), advanced facial irritation symptoms (n = 1), and electrode slip-out (n = 1). Mean preoperative and postoperative CI thresholds were 44.0 ± 9.46 dBnHL and 39.19 ± 8.89 dBnHL (p < .068), respectively. Conclusion and Significance Caregiver education, surgical technique advances, flap design, and extensive antibiotic use may decrease the revision surgery rate. The lack of post-revision deterioration of the hearing threshold contributed to well-being in patients with CI.

Mouse models reveal P2X2 receptor-mediated hearing adaptation is an indicator of noise-induced hearing loss vulnerability

Transgenic mouse models targeting the P2rx2 gene encoding the ATP-gated ion channel P2X2R subunit have revealed a cochlear humoral control mechanism where sustained elevation of background noise drives adaptation of hearing sensitivity over several minutes, requiring hours to reset (evident as “temporary threshold shift” in ABR thresholds, and reduction in DPOAE amplitudes; Housley et al. PNAS 2013, Cederholm et al. Purinergic Signalling 2019, Housley et al. Curr. Opinion. Physiol. 2020). Exposure of P2rx2 knockout (KO) mice to sustained noise (85 dB SPL) fails to elicit the ∼15 dB reduction in ABR thresholds that wildtype (WT) controls demonstrate. While acute hearing sensitivity is maintained, when these P2rx2KO mice are exposed to long-term moderate (75 dB SPL) white noise, they develop high frequency hearing loss not seen in WT controls. This “Purinergic Hearing Adaptation” otoprotection postulate is supported by human studies, where P2RX2 loss of function mutations lead to autosomal dominant progressive hearing loss that is exacerbated with exposure to environmental noise (DFNA41; Yan et al. PNAS 2013). Thus, noise-mediated release of ATP into the cochlear partition drives sustained suppression of the “cochlear amplifier,” supporting cochlear sensori-neural function across a lifetime that complements dynamic medial olivocochlear efferent-based otoprotection.

Absence of Embigin accelerates hearing loss and causes sub-viability, brain and heart defects in C57BL/6N mice due to interaction with Cdh23ahl

Mouse studies continue to help elaborate upon the genetic landscape of mammalian disease and the underlying molecular mechanisms. Here, we have investigated an Embigintm1b allele maintained on a standard C57BL/6N background and on a co-isogenic C57BL/6N background in which the Cdh23ahl allele has been "repaired." The hypomorphic Cdh23ahl allele is present in several commonly used inbred mouse strains, predisposing them to progressive hearing loss, starting in high-frequency regions. Absence of the neural cell adhesion molecule Embigin on the standard C57BL/6N background leads to accelerated hearing loss and causes sub-viability, brain and cardiac defects. Contrastingly, Embigintm1b/tm1b mice maintained on the co-isogenic "repaired" C57BL/6N background exhibit normal hearing and viability. Thus Embigin genetically interacts with Cdh23. Importantly, our study is the first to demonstrate an effect of the common Cdh23ahl allele outside of the auditory system, which has important ramifications for genetic studies involving inbred strains carrying this allele.

Neuro-otological manifestations in Fabry disease-aretrospective single center study

Fabry disease (FD) is one of the X‑linked lysosomal storage diseases that can affect any organ. They have aspecific lysosomal dysfunction in common, which results in substrate accumulation in lysosomes instead of metabolite degradation. Due to the deficiency/absence of α‑galactosidase, globotriaosylceramides (Gb3) are deposited in lysosomes of the organs. In addition to acroparesthesia, angiokeratomas, autonomic dysfunction, vortex keratopathies, ischemic cerebral or cardiac complications and chronic renal failure, also vestibulocochlear dysfunctions with sudden or progressive asymmetric hearing loss, tinnitus and vertigo may be observed. In this retrospective study, 33patients (men = 16 and women = 17) with FD were evaluated. All patients presented to us in interdisciplinary cooperation as part of routine examinations by the specialized center for lysosomal storage diseases of the in-house department of nephrology. This presentation is carried out as ascreening examination independent of neuro-otological symptoms. The mean age at diagnosis was 34.76 (±11.55) years. The first presentation in our ENT department was at 40.45 (±11.71) years. We were able to demonstrate asignificant correlation between neurological symptoms or apoplexy and hearing loss (p = 0.001) and between cardiac manifestations and hearing loss (p = 0.024). Hearing loss is apotential symptom of Fabry disease and is not limited to the classic male phenotype. Due to possible positive correlations with neurological and cardiological manifestations of the disease, routine ENT screening examinations should be carried out to be able to identify and treat neuro-otological deficits at an early stage. In addition, FD should also be considered and tested as adifferential diagnosis, especially in younger patients with sudden unilateral or bilateral hearing loss and afamily history.

Novel Variant in CEP250 Causes Protein Mislocalization and Leads to Nonsyndromic Autosomal Recessive Type of Progressive Hearing Loss.

Genetic hearing loss is the most common hereditary sensorial disorder. Though more than 120 genes associated with deafness have been identified, unveiled causative genes and variants of diverse types of hearing loss remain. Herein, we identified a novel nonsense homozygous variant in CEP250 (c.3511C>T; p.Gln1171Ter) among the family members with progressive moderate sensorineural hearing loss in nonsyndromic autosomal recessive type but without retinal degeneration. CEP250 encodes C-Nap1 protein belonging to the CEP protein family, comprising 30 proteins that play roles in centrosome aggregation and cell cycle progression. The nonsense variant in CEP250 led to the early truncating protein of C-Nap1, which hindered centrosome localization; heterologous expression of CEP250 (c.3511C>T) in NIH3T3 cells within cilia expression condition revealed that the truncating C-Nap1 (p.Gln1171Ter) was not localized at the centrosome but was dispersed in the cytosol. In the murine adult cochlea, Cep250 was expressed in the inner and outer hair cells. Knockout mice of Cep250 showed significant hair cell degeneration and progressive hearing loss in auditory brainstem response. In conclusion, a nonsense variant in CEP250 results in a deficit of centrosome localization and hair cell degeneration in the cochlea, which is associated with the progression of hearing loss in humans and mice.

Human blood-labyrinth barrier model to study the effects of cytokines and inflammation.

Hearing loss is one of the 10 leading causes of disability worldwide. No drug therapies are currently available to protect or restore hearing. Inner ear auditory hair cells and the blood-labyrinth barrier (BLB) are critical for normal hearing, and the BLB between the systemic circulation and stria vascularis is crucial for maintaining cochlear and vestibular homeostasis. BLB defects are associated with inner ear diseases that lead to hearing loss, including vascular malformations, inflammation, and Meniere's disease (MD). Antibodies against proteins in the inner ear and cytokines in the cochlea, including IL-1α, TNF-α, and NF-kβ, are detected in the blood of more than half of MD patients. There is also emerging evidence of inner ear inflammation in some diseases, including MD, progressive sensorineural hearing loss, otosclerosis, and sudden deafness. Here, we examined the effects of TNF-α, IL6, and LPS on human stria vascularis-derived primary endothelial cells cultured together with pericytes in a Transwell system. By measuring trans-endothelial electrical resistance, we found that TNF-α causes the most significant disruption of the endothelial barrier. IL6 had a moderate influence on the barrier, whereas LPS had a minimal impact on barrier integrity. The prominent effect of TNF-α on the barrier was confirmed in the expression of the major junctional genes responsible for forming the tight endothelial monolayer, the decreased expression of ZO1 and OCL. We further tested permeability using 2 μg of daptomycin (1,619 Da), which does not pass the BLB under normal conditions, by measuring its passage through the barrier by HPLC. Treatment with TNF-α resulted in higher permeability in treated samples compared to controls. LPS-treated cells behaved similarly to the untreated cells and did not show differences in permeability compared to control. The endothelial damage caused by TNF-α was confirmed by decreased expression of an essential endothelial proteoglycan, syndecan1. These results allowed us to create an inflammatory environment model that increased BLB permeability in culture and mimicked an inflammatory state within the stria vascularis.

Age-related changes in P2Y receptor signalling in mouse cochlear supporting cells.

Our sense of hearing depends on the function of a specialised class of sensory cells, the hair cells, which are found in the organ of Corti of the mammalian cochlea. The unique physiological environment in which these cells operate is maintained by a syncitium of non-sensory supporting cells, which are crucial for regulating cochlear physiology and metabolic homeostasis. Despite their importance for cochlear function, the role of these supporting cells in age-related hearing loss, the most common sensory deficit in the elderly, is poorly understood. Here, we investigated the age-related changes in the expression and function of metabotropic purinergic receptors (P2Y1 , P2Y2 and P2Y4 ) in the supporting cells of the cochlear apical coil. Purinergic signalling in supporting cells is crucial during the development of the organ of Corti and purinergic receptors are known to undergo changes in expression during ageing in several tissues. Immunolabelling and Ca2+ imaging experiments revealed a downregulation of P2Y receptor expression and a decrease of purinergic-mediated calcium responses after early postnatal stages in the supporting cells. An upregulation of P2Y receptor expression was observed in the aged cochlea when compared to 1month-old adults. The aged mice also had significantly larger calcium responses and displayed calcium oscillations during prolonged agonist applications. We conclude that supporting cells in the aged cochlea upregulate P2Y2 and P2Y4 receptors and display purinergic-induced Ca2+ responses that mimic those observed during pre-hearing stages of development, possibly aimed at limiting or preventing further damage to the sensory epithelium. KEY POINTS: Age-related hearing loss is associated with lower hearing sensitivity and decreased ability to understand speech. We investigated age-related changes in the expression and function of metabotropic purinergic (P2Y) receptors in cochlear non-sensory supporting cells of mice displaying early-onset (C57BL/6N) and late-onset (C3H/HeJ) hearing loss. The expression of P2Y1 , P2Y2 and P2Y4 receptors in the supporting cells decreased during cochlear maturation, but that of P2Y2 and P2Y4 was upregulated in the aged cochlea. P2Y2 and P2Y4 receptors were primarily responsible for the ATP-induced Ca2+ responses in the supporting cells. The degree of purinergic expression upregulation in aged supporting cells mirrored hearing loss progression in the different mouse strains. We propose that the upregulation of purinergic-mediated signalling in the aged cochlea is subsequent to age-related changes in the hair cells and may act as a protective mechanism to limit or to avoid further damage to the sensory epithelium.

Evaluation of hearing levels and vestibular function and the impact on cognitive performance in (pre)-symptomatic patients with DFNA9: protocol for a prospective longitudinal study (Rosetta study)

IntroductionUntreated hearing loss is the largest potentially modifiable risk factor for dementia. Additionally, vestibular dysfunction has been put forward as a potential risk factor for accelerated cognitive decline. Patients with...

Cingulin regulates hair cell cuticular plate morphology and is required for hearing in human and mouse

Cingulin (CGN) is a cytoskeleton‐associated protein localized at the apical junctions of epithelial cells. CGN interacts with major cytoskeletal filaments and regulates RhoA activity. However, physiological roles of CGN in development and human diseases are currently unknown. Here, we report a multi‐generation family presenting with autosomal dominant non‐syndromic hearing loss (ADNSHL) that co‐segregates with a CGN heterozygous truncating variant, c.3330delG (p.Leu1110Leufs*17). CGN is normally expressed at the apical cell junctions of the organ of Corti, with enriched localization at hair cell cuticular plates and circumferential belts. In mice, the putative disease‐causing mutation results in reduced expression and abnormal subcellular localization of the CGN protein, abolishes its actin polymerization activity, and impairs the normal morphology of hair cell cuticular plates and hair bundles. Hair cell‐specific Cgn knockout leads to high‐frequency hearing loss. Importantly, Cgn mutation knockin mice display noise‐sensitive, progressive hearing loss and outer hair cell degeneration. In summary, we identify CGN c.3330delG as a pathogenic variant for ADNSHL and reveal essential roles of CGN in the maintenance of cochlear hair cell structures and auditory function.

Degradation of cochlear Connexin26 accelerate the development of age-related hearing loss.

The GJB2 gene, encoding Connexin26 (Cx26), is one of the most common causes of inherited deafness. Clinically, mutations in GJB2 cause congenital deafness or late-onset progressive hearing loss. Recently, it has been reported that Cx26 haploid deficiency accelerates the development of age-related hearing loss (ARHL). However, the roles of cochlear Cx26 in the hearing function of aged animals remain unclear. In this study, we revealed that the Cx26 expression was significantly reduced in the cochleae of aged mice, and further explored the underlying molecular mechanism for Cx26 degradation. Immunofluorescence co-localization results showed that Cx26 was internalized and degraded by lysosomes, which might be one of the important ways for Cx26 degradation in the cochlea of aged mice. Currently, whether the degradation of Cx26 in the cochlea leads directly to ARHL, as well as the mechanism of Cx26 degradation-related hearing loss are still unclear. To address these questions, we generated mice with Cx26 knockout in the adult cochlea as a model for the natural degradation of Cx26. Auditory brainstem response (ABR) results showed that Cx26 knockout mice exhibited high-frequency hearing loss, which gradually progressed over time. Pathological examination also revealed the degeneration of hair cells and spiral ganglions, which is similar to the phenotype of ARHL. In summary, our findings suggest that degradation of Cx26 in the cochlea accelerates the occurrence of ARHL, which may be a novel mechanism of ARHL.

The natural history, clinical outcomes, and genotype-phenotype relationship of otoferlin-related hearing loss: a systematic, quantitative literature review.

Congenital hearing loss affects one in 500 newborns. Sequence variations in OTOF, which encodes the calcium-binding protein otoferlin, are responsible for 1-8% of congenital, nonsyndromic hearing loss and are the leading cause of auditory neuropathy spectrum disorders. The natural history of otoferlin-related hearing loss, the relationship between OTOF genotype and hearing loss phenotype, and the outcomes of clinical practices in patients with this genetic disorder are incompletely understood because most analyses have reported on small numbers of cases with homogeneous OTOF genotypes. Here, we present the first systematic, quantitative literature review of otoferlin-related hearing loss, which analyzes patient-specific data from 422 individuals across 61 publications. While most patients display a typical phenotype of severe-to-profound hearing loss with prelingual onset, 10-15% of patients display atypical phenotypes, including mild-to-moderate, progressive, and temperature-sensitive hearing loss. Patients' phenotypic presentations appear to depend on their specific genotypes. For example, non-truncating variants located in and immediately downstream of the C2E calcium-binding domain are more likely to produce atypical phenotypes. Additionally, the prevalence of certain sequence variants and their associated phenotypes varies between populations due to evolutionary founder effects. Our analyses also suggest otoacoustic emissions are less common in older patients and those with two truncating OTOF variants. Critically, our review has implications for the application and limitations of clinical practices, including newborn hearing screenings, hearing aid trials, cochlear implants, and upcoming gene therapy clinical trials. We conclude by discussing the limitations of available research and recommendations for future studies on this genetic cause of hearing loss.

Systemic gene therapy rescues retinal dysfunction and hearing loss in a model of Norrie disease.

Deafness affects 5% of the world's population, yet there is a lack of treatments to prevent hearing loss due to genetic causes. Norrie disease is a recessive X-linked disorder, caused by NDP gene mutation. It manifests as blindness at birth and progressive sensorineural hearing loss, leading to debilitating dual sensory deprivation. To develop a gene therapy, we used a Norrie disease mouse model (Ndptm1Wbrg ), which recapitulates abnormal retinal vascularisation and progressive hearing loss. We delivered human NDP cDNA by intravenous injection of adeno-associated viral vector (AAV)9 at neonatal, juvenile and young adult pathological stages and investigated its therapeutic effects on the retina and cochlea. Neonatal treatment prevented the death of the sensory cochlear hair cells and rescued cochlear disease biomarkers as demonstrated by RNAseq and physiological measurements of auditory function. Retinal vascularisation and electroretinograms were restored to normal by neonatal treatment. Delivery of NDP gene therapy after the onset of the degenerative inner ear disease also ameliorated the cochlear pathology, supporting the feasibility of a clinical treatment for progressive hearing loss in people with Norrie disease.

Metastatic Malignant Glomus Jugulare Tumor: A Rare Case Report with Clinical Manifestations and Treatment Approach.

BACKGROUND Paragangliomas are neuroendocrine neoplasms derived from paraganglia of the sympathetic and parasympathetic nervous systems. Parasympathetic ganglia-derived tumors, also called non-chromaffin, are located almost exclusively in the neck and skull base and are usually non-secretory and inactive. A case of malignant glomus jugulare with a metastatic cervical lymph node is described here. CASE REPORT A 24-year-old woman was referred to an otolaryngology clinic for concern of voice change for 1 month, which was associated with right progressive hearing loss, pulsating tinnitus, and right facial weakness. A clinical examination revealed a reddish mass in the right ear behind an intact tympanic membrane with right facial weakness of House-Brackmann grade VI. A bedside flexible nasopharyngoscopy revealed an immobile right vocal fold. A computed tomography scan of the brain revealed a destructive lesion within the right jugular foramen. The patient underwent embolization followed by glomus tumor resection via infra-temporal fossa with Fisch type A approach. Pathology revealed that the tumor was an infiltrative epithelioid tumor with a spindle and nesting pattern separated by fibrovascular stroma. The submitted lateral neck lymph node revealed a metastatic tumor. CONCLUSIONS Glomus jugulare tumors are uncommon paragangliomas, and malignant behavior with metastasis is extremely rare. Metastatic tumors are often associated with facial and vagal nerves palsy. There are no histological features that distinguish malignant glomus jugulare tumors. Malignant neoplasms are characterized by the presence of metastases. Tumors of the glomus jugulare that are malignant are treated with surgery, radiotherapy, or both. However, our search of the literature revealed no clear guidelines, given the scarcity of cases. Moreover, the presence of metastasis increases the risk of death.

MTORC2 regulates auditory hair cell structure and function

mTOR broadly controls cell growth, but little is known about the role of mTOR complex 2 (mTORC2) in the inner ear. To investigate the role of mTORC2 in sensory hair cells (HCs), we generated HC-specific Rictor knockout (HC-RicKO) mice. HC-RicKO mice exhibited early-onset, progressive, and profound hearing loss. Increased DPOAE thresholds indicated outer HC dysfunction. HCs are lost, but this occurs after hearing loss. Ultrastructural analysis revealed stunted and absent stereocilia in outer HCs. In inner HCs, the number of synapses was significantly decreased and the remaining synapses displayed a disrupted actin cytoskeleton and disorganized Ca2+ channels. Thus, the mTORC2 signaling pathway plays an important role in regulating auditory HC structure and function via regulation of the actin cytoskeleton. These results provide molecular insights on a central regulator of cochlear HCs and thus hearing.

A Case Report of Riboflavin Treatment and Cochlear Implants in a 4-Year-Old Girl with Progressive Hearing Loss and Delayed Speech Development: Brown-Vialetto-Van Laere Syndrome.

BACKGROUND Brown-Vialetto-Van Laere (BVVL) syndrome is a rare autosomal recessive disorder caused by mutations in intestinal riboflavin transporter genes, resulting in a motor neuron disorder of childhood, which can be associated with sensorineural deafness. This report describes a 4-year-old Polish girl with progressive hearing loss and delayed speech development diagnosed with Brown-Vialetto-Van Laere syndrome who was treated with riboflavin (vitamin B2) and cochlear implants. CASE REPORT The case report concerns a girl from Poland who, at the age of 2 years 10 months, developed progressive atypical neurological symptoms of unknown etiology: ataxia of the upper and lower limbs, gait abnormalities, generalized muscle weakness, visual and hearing problems, and regression of speech development. A karyotype study (whole-exome sequencing) revealed alterations within SLC52A2, leading to the diagnosis of Brown-Vialetto-Van Laere syndrome and initiation of high-dose riboflavin treatment. As a 4-year-old child, she presented to the Institute of Physiology and Pathology of Hearing-World Hearing Center in Poland with progressive hearing loss and speech regression. Hearing tests revealed bilateral profound sensorineural hearing loss with auditory neuropathy. Surgical treatment was applied in the form of bilateral cochlear implantation. CONCLUSIONS This report shows the importance of genetic testing in infants who present with atypical symptoms or signs. In this case, the diagnosis of Brown-Vialetto-Van Laere syndrome resulted in timely correction of the genetic riboflavin (vitamin B2) deficiency and improved hearing following the use of cochlear implants.

Congenital Cytomegalovirus-Associated Sensorineural Hearing Loss in Children: Identification Following Universal Newborn Hearing Screening, Effect of Antiviral Treatment, and Long-Term Hearing Outcomes.

Congenital cytomegalovirus (cCMV) is the most common cause of nongenetic sensorineural hearing loss (SNHL) in children. We examined the longitudinal hearing outcomes of children with cCMV in relation to their newborn hearing screening findings, and their use of antiviral therapy. The study was based on a retrospective chart review using a database of pediatric patients (N = 445) seen at the University of Minnesota Lions clinic. Chart review identified infants with cCMV, and records were reviewed for information about universal newborn hearing screen (UNHS) results, the clinical course of SNHL, and the use of antiviral therapy. A total of 44 children were identified with cCMV. In this group, 33 (75%) had SNHL of varying degree and age at onset. Notably, 17 (39%) children passed UNHS bilaterally. Of those children, 6 (35%) ultimately acquired bilateral or unilateral SNHL, detected at a mean age of 20 months (median age, 12 months). Five out of 10 children (50%) that did not pass UNHS in one ear acquired late-onset hearing loss in the contralateral ear, identified at a mean age of 24 months (median age, 4 months). Eleven (25%) children passed UNHS bilaterally and continued to demonstrate normal hearing in both ears at their most recent follow-up visit at a mean age of 19 months (SD, 18 months). Of the 33 children with cCMV and SNHL, 18 (55%) received antiviral medication (ganciclovir and/or valganciclovir). While, on average, both treated and untreated ears experienced a progression of hearing loss over time, the group that received antiviral treatment experienced less overall hearing change compared with the untreated group (baseline-adjusted expected mean difference, -10.5 dB; 95% confidence interval, -28.1 to 7.2 dB). Among children with cCMV included in this study who passed UNHS in both ears, 35% demonstrated delayed-onset SNHL. Notably, of those children who referred unilaterally, 50% later demonstrated SNHL in the contralateral ear. These findings have implications for audiological monitoring, and potentially antiviral therapy, of children with cCMV. As implementation of universal cCMV screening moves forward, a key aspect of follow-up will be appropriate long-term audiologic monitoring.

Bilateral Sensorineural Hearing Loss Related to a Skull Base Spontaneous Cerebrospinal Fluid Leak: A Case Report and Literature Review.

Spontaneous intracranial hypotension (SIH) is a rare condition characterized by orthostatic headache, pulsatile tinnitus, vertigo, nausea, and fluctuating hearing loss; this latter seems to be due to the development of cochlear endolymphatic hydrops following negative cerebrospinal fluid (CSF) pressure transmitted to the perilymphatic space through a patent cochlear aqueduct. We here describe a case of bilateral progressive sensorineural hearing loss (SNHL) due to intracranial hypotension caused by an undiagnosed spontaneous CSF leak from a skull base defect in a middle-aged woman. To the best of our knowledge, this is the first report describing a SNHL in a patient affected by SIH secondary to sphenoidal CSF leak.