Project description:BackgroundHearing loss (HL) is a well-known feature of Fabry disease (FD). Its presence and characteristics have mainly been studied in adult patients, while only limited data are available on the presence and degree of HL in children with FD. This prompted us to study hearing sensitivity in pediatric FD patients.MethodsAll available audiograms of the Dutch and Norwegian children with FD were retrospectively collected. First, hearing sensitivity was determined by studying hearing thresholds at low, high, and ultra-high frequencies in children with FD and comparing them to zero dB HL, i.e., healthy children. In addition, the presence and type of slight/mild HL (defined as hearing thresholds at low frequencies of 25-40 dB HL) and moderate to severe HL (hearing thresholds >40 dB HL) at first visit were analyzed. If available, follow-up data were used to estimate the natural course of hearing sensitivity and HL in children with FD.ResultsOne-hundred-thirteen audiograms of 47 children with FD (20 boys, median age at first audiogram 12.0 (range 5.1-18.0) years) were analyzed. At baseline, slight/mild or moderate to severe HL was present in three children (6.4%, 2 boys). Follow-up measurements showed that three additional children developed HL before the age of 18. Of these six children, five had sensorineural HL, most likely caused by FD. Compared to healthy children (zero dB HL), FD children showed increased hearing thresholds at all frequencies (p < 0.01), which was most prominent at ultra-high frequencies (>8 kHz). Hearing sensitivity at these ultra-high frequencies deteriorated in a period of 5 years of follow-up.ConclusionA minority of children with FD show slight/mild or moderate to severe HL, but their hearing thresholds are poorer than the reference values for normal-hearing children. Clinical trials in FD children should demonstrate whether HL can be prevented or reversed by early treatment and should specifically study ultra-high frequencies.
Project description:IntroductionSensorineural hearing loss (SNHL) has been reported to occur at increased frequency in the pediatric sickle cell disease (SCD) population, likely secondary to ototoxic medication regimens and repeat sickling events that lead to end organ damage. Risk and protective factors of SNHL in this population are not fully characterized. The objective of this study was to describe audiology results in children with SCD and the prevalence and sequelae of SNHL.MethodsA comprehensive clinical database of 2600 pediatric SCD patients treated at 1 institution from 2010-16 was retrospectively reviewed to identify all patients who were referred for audiologic testing. Audiologic test results, patient characteristics, and SCD treatments were reviewed.Results181 SCD children (97 male, 153 HbSS) underwent audiologic testing, with 276 total audiology encounters, ranging 1-9 per patient. Mean age at first audiogram was 8.9 ± 5.2 years. 29.8% had prior cerebrovascular infarct and an additional 25.4% had prior abnormal transcranial Doppler screens documented at time of first audiogram. Overall, 13.3% had documented hearing loss, with 6.6% SNHL. Mean pure tone average (PTA) among patients with SNHL ranged from mild to profound hearing loss (Right: 43.3 ± 28.9, Left: 40.8 ± 29.7), sloping to more severe hearing loss at higher frequencies.ConclusionsHearing loss was identified in a significant subset of children with SCD and the hearing loss ranged from normal to profound. Though the overall prevalence of SNHL in SCD patients was low, baseline audiology screening should be considered.
Project description:IntroductionSensorineural hearing loss affects a high percentage of the population. Ototoxicity is a serious and pervasive problem in patients treated with cisplatin. Strategies to ameliorate ototoxicity without compromising on antitumor activity of treatments are urgently needed. Similar problems occur with aminoglycoside antibiotic therapy for infections. Noise-induced hearing loss affects a large number of people. The use of ear protection is not always possible or effective. The prevention of hearing loss with drug therapy would have a huge impact in reducing the number of people with hearing loss from these major causes.Areas coveredThis review discusses significant research findings dealing with the use of protective agents against hearing loss caused by cisplatin, aminoglycoside antibiotics and noise trauma. The efficacy in animal studies and the application of these protective agents in clinical trials that are ongoing are presented.Expert opinionThe reader will gain new insights into current and projected future strategies to prevent sensorineural hearing loss from cisplatin chemotherapy, aminoglycoside antibiotic therapy and noise exposure. The future appears to offer numerous agents to prevent hearing loss caused by cisplatin, aminoglycoside antibiotics and noise. Novel delivery systems will provide ways to guide these protective agents to the desired target areas in the inner ear and circumvent problems with therapeutic interference of antitumor and antibiotics agents as well as minimize undesired side effects.
Project description:Hereditary hearing loss (HL) is a genetically heterogeneous disorder affecting people worldwide. The implementation of advanced sequencing technologies has significantly contributed to the identification of novel genes involved in HL. In this study, probands of two Turkish families with non-syndromic moderate HL were subjected to exome sequencing. The data analysis identified the c.600G > A (p.Thr200Thr) and c.1863dupG (p.His622fs) variants in GPR156, which co-segregated with the phenotype as an autosomal recessive trait in the respective families. The in silico predictions and a minigene assay showed that the c.600G > A variant disrupts mRNA splicing. This gene belongs to the family of G protein-coupled receptors whose function is not well established in the inner ear. GPR156 variants have very recently been reported to cause HL in three families. Our study from a different ethnic background confirms GPR156 as a bona fide gene involved in HL in humans. Further investigation towards the understanding of the role of GPCRs in the inner ear is warranted.
Project description:Introduction: Sensorineural hearing loss (SNHL) is a prevalent sensory deficit presenting commonly as age-related hearing loss. Other forms of SNHL include noise-induced and sudden SNHL. Recent evidence has pointed to oxidative stress as a common pathogenic pathway in most subtypes of acquired SNHL. MicroRNAs (miRNAs) are small non-coding RNA sequences that suppress target mRNA expression and affect downstream processes. Many studies have shown that miRNAs are integral biomolecules in hypoxia-adaptive responses. They also promote apoptosis in response to oxidative stress resulting in SNHL. Our hypothesis is that miRNAs are involved in the pathophysiological responses to hypoxia and oxidative stress that result in SNHL. This study reviews the evidence for hypoxia-adaptive miRNAs (hypoxamiRs) in different types of acquired SNHL and focuses on miRNAs involved in hypoxia driven SNHL. Methods: Electronic bibliographic databases PubMed, Ovid MEDLINE, Ovid EMBASE, and Web of Science Core Collection were searched independently by two investigators for articles published in English from the inception of individual databases to the end of July 2020. The text word or medical subject heading searches of all fields, titles, abstracts, or subject headings depending on the database were undertaken with combinations of the words "microRNAs", "hypoxia", "hypoxamiRs", "oxidative stress", "ischemia" and "hearing loss". The reference lists of studies meeting the inclusion criteria were searched to identify additional relevant studies. The inclusion criteria included relevant clinical studies with human subjects, animals, and in vitro experiments. The risk of bias was assessed using the Cochrane risk of bias assessment tool for human studies and the Systematic Review Center for Laboratory animal Experimentation (SYRCLE) a risk of bias assessment tool for animal model and in vitro studies. Results: A total of 15 primary articles were selected for full text screening after excluding duplicates, reviews, retracted articles, and articles not published in English. All nine articles meeting the study inclusion criteria were from animal or in vitro model studies and were assessed to be at low risk of bias. miRNAs miR-34a and miR-29b were reported to be involved in SNHL in inner ear cell models exposed to oxidative stress. Signaling pathways Sirtuin 1/peroxisome proliferator-activated receptor gamma coactivator-1-alpha (SIRT1/PGC-1α), SIRT1/p53, and SIRT1/hypoxia-inducible factor 1-alpha (HIF-1α) were identified as underlying pathways involved in acquired SNHL. Conclusion: There is evidence that miR-34a and -29b are involved in hypoxia-driven and other causes of oxidative stress-related acquired SNHL. Further studies are required to determine if these findings are clinically applicable.
Project description:BackgroundSensorineural hearing loss (SNHL) has been suggested to occur in patients with Lyme neuroborreliosis (LNB); however, a clear association has never been documented. The present study prospectively investigated the development of SNHL in patients admitted for treatment of LNB using distortion-product-oto-acoustic emissions (DPOAE) as a measure of cochlear function.MethodsDOAE were measured in patients with LNB on the day of diagnosis, during treatment, and 30-60 days after discharge. Frequencies were categorized as Low (1, 1.5, 2 kHz), Mid (3, 4, 5 kHz), Mid-high (6, 7, 8 kHz), and High (9, 10 kHz). Pure Tone Audiometry (PTA3) was performed at discharge and 60 days after. Patients were treated with i.v. ceftriaxone or oral doxycycline for 14 days according to guidelines.ResultsDPOAE measurements were obtained in 25 patients with LNB at admission and in 18 patients at follow-up. Median age was 56 years (IQR, 48-64 years), and 16 (67%) were men. Fourteen (78%) of 18 patients showed improvement in Emission Threshold Levels (ETL) from admission to follow-up in low, mid-, and mid-high frequency categories, where ETLs increased by median levels of 3.2 (-4.1 to 8.3), 7.5 (-2.8 to 9.8), and 4.7 dB (-4.3 to 10.1). A decline was observed in the high frequency category, median -3.3 dB (-9.1 to 6.7). SNHL defined by pure tone average (PTA3) >20 dB was present in 11 out of 23 (48%) at discharge and in 9 out of 16 patients (56%) 60 days after discharge, which differed significantly from matched controls (Mann-Whitney test, p = 0.036).ConclusionLNB can lead to cochlear outer-hair cell dysfunction, resulting in temporary and long-term SNHL.
Project description:Fabry disease, OMIM 301500, is a progressive multisystem storage disorder due to the deficiency of alpha-galactosidase A (GALA). Neurological and vascular manifestations of this disorder with regard to hearing loss have not been analysed quantitatively in large cohorts. We conducted a retrospective cross sectional analysis of hearing loss in 109 male and female patients with Fabry disease who were referred to and seen at the Clinical Center of the National Institutes of Health, Bethesda, MD, USA on natural history and enzyme replacement study protocols. There were 85 males aged 6-58 years (mean 31 years, SD 13) and 24 females aged 22-72 years (mean 42 years, SD 12). All patients underwent a comprehensive audiological evaluation. In addition, cerebral white matter lesions, peripheral neuropathy, and kidney function were quantitatively assessed. HL(95), defined as a hearing threshold above the 95th percentile for age and gender matched normal controls, was present in 56% [95% CI (42.2-67.2)] of the males. Prevalence of HL(95) was lower in the group of patients with residual GALA enzyme activity compared with those without detectable activity (33% versus 63%) HL(95) was present in the low-, mid- and high-frequency ranges for all ages. Male patients with HL(95) had a higher microvascular cerebral white matter lesion load [1.4, interquartile range (IQR) 0-30.1 +/- versus 0, IQR 0-0], more pronounced cold perception deficit [19.4 +/- 5.5 versus 13.5 +/- 5.5 of just noticeable difference (JND) units] and lower kidney function [creatinine: 1.6 +/- 1.2 versus 0.77 +/- 0.2 mg/dl; blood urea nitrogen (BUN): 20.1 +/- 14.1 versus 10.3 +/- 3.28 mg/dl] than those without HL(95) (P < 0.001). Of the females, 38% had HL(95). There was no significant association with cold perception deficit, creatinine or BUN in the females. Word recognition and acoustic reflexes analyses suggested a predominant cochlear involvement. We conclude that hearing loss involving all frequency regions significantly contributes to morbidity in patients with Fabry disease. Our quantitative analysis suggests a correlation of neuropathic and vascular damage with hearing loss in the males. Residual GALA activity appears to have a protective effect against hearing loss.
Project description:IntroductionTo compare inpatient treated patients with idiopathic (ISSNHL) and non-idiopathic sudden sensorineural hearing loss (NISSNHL) regarding frequency, hearing loss, treatment and outcome.MethodsAll 574 inpatient patients (51% male, median age: 60 years) with ISSNHL and NISSNHL, who were treated in federal state Thuringia in 2011 and 2012, were included retrospectively. Univariate and multivariate statistical analyses were performed.ResultsISSNHL was diagnosed in 490 patients (85%), NISSNHL in 84 patients (15%). 49% of these cases had hearing loss due to acute otitis media, 37% through varicella-zoster infection or Lyme disease, 10% through Menière disease and 7% due to other reasons. Patients with ISSNHL and NISSNHL showed no difference between age, gender, side of hearing loss, presence of tinnitus or vertigo and their comorbidities. 45% of patients with ISSNHL and 62% with NISSNHL had an outpatient treatment prior to inpatient treatment (p < 0.001). The mean interval between onset of hearing loss to inpatient treatment was shorter in ISSNHL (7.7 days) than in NISSNHL (8.9 days; p = 0.02). The initial hearing loss of the three most affected frequencies in pure-tone average (3PTAmax) scaled 72.9 dBHL ± 31.3 dBHL in ISSNHL and 67.4 dBHL ± 30.5 dBHL in NISSNHL. In the case of acute otitis media, 3PTAmax (59.7 dBHL ± 24.6 dBHL) was lower than in the case of varicella-zoster infection or Lyme disease (80.11 dBHL ± 34.19 dBHL; p = 0.015). Mean absolute hearing gain (Δ3PTAmaxabs) was 8.1 dB ± 18.8 dB in patients with ISSNHL, and not different in NISSNHL patients with 10.2 dB ± 17.6 dB. A Δ3PTAmaxabs ≥ 10 dB was reached in 34.3% of the patients with ISSNHL and to a significantly higher rate of 48.8% in NISSNHL patients (p = 0.011).ConclusionsISSNHL and NISSNHL show no relevant baseline differences. ISSNHL tends to have a higher initial hearing loss. NISSHNL shows a better outcome than ISSNHL.