Susceptibility of the sympathectomized ear to noise-induced hearing loss

Unilaterally sympathectomiced rats were exposed to 100 dB L_eq frequency-modulated noise for I month. Normotensive as well as spontaneously hypertensive animals (with a blood pressure of above 200 mmHg) were investigated. Auditory sensitivity was determined by auditory brainstem responses to 1/3-octave filtered sine waves in the frequency range 0.8–20.0 kHz. In addition, a morphological analysis was carried out. It was found that the sympathetic innervation to the inner ear of the rat originated in, or passed through the ipsilateral superior cervical ganglion. Sympathectomy did not alter pre-exposure hearing thresholds nor influence the size of the noise-induced hearing loss either in 3 or 11 months old hypertensive rats, or in normotensive rats of 11 months. A slightly smaller loss was seen in the sympathectomized side in young normotensive rats. It was concluded that the sympathetic does not exert a protection of the inner ear against functional disturbances in hypertension, neither during basal metabolic condition nor during extreme conditions, i.e. during noxious noise exposure.     

Cryptococcal meningitis presented as sudden hearing loss: A case study

BackgroundThis case report emphasizes that cryptococcal meningitis could be uncommonly presented to otolaryngologists as sudden onset of hearing loss, especially in patients with underlying diseases that could cause immunocompromise, and highlights the importance of differentiated diagnosis on sudden hearing loss before steroid therapy. It also demonstrates that prompt and sufficient fungicidal therapy with appropriate supportive treatment is crucial for a good prognosis on cryptococcal meningitis.Case presentationA diabetic adult with untreated chronic hepatitis B was admitted complaining of sudden onset of left-sided hearing loss, following unexpected aggravating headache with meningeal signs after hospitalization with days of intratympanic steroid therapy. Cryptococcal meningitis was confirmed through lumbar puncture showing positive India ink staining and microbial culture of the cerebrospinal fluid (CSF). Fortunately, the patient recovered after prompt and adequate fungicidal therapy plus appropriate supportive treatment at last, though persistent hearing loss remained.ConclusionsCryptococcal meningitis could be presented in a very concealed way as sudden hearing loss, especially in patients with underlying diseases that could cause immunosuppression. Differentiated diagnosis on sudden hearing loss before steroid therapy is important.     

Clinical and genetic studies in Spanish patients with Usher syndrome type II: description of new mutations and evidence for a lack of genotype--phenotype correlation

Patients with Usher syndrome type II (USH2) show moderate-to-severe hearing loss (HL), retinitis pigmentosa and normal vestibular function. The progression of HL remains controversial. To evaluate whether a phenotype-genotype correlation exists regarding the issue of progression of HL, only USH2 patients with a defined genotype were selected. Ophthalmologic, vestibular and audiometric examination along with a mutation analysis of the USH2A gene (exons 1--21) was performed in twenty-eight Spanish USH2 patients. Ten different pathogenic mutations and 17 sequence variants not associated with the disease were found. Six of the 10 mutations are novel. Disease alleles were identified in 13 of the 28 families tested. Eight of these 13 families had a mutation found in both alleles. In the other five families, only one mutation was identified. The phenotypic data provide evidence for the existence of phenotypic differences between patients with the same genotype. These differences were observed at both the interfamilial and intrafamilial levels.     

Acoustic perception of high-pitch tones by patients with bronchial asthma

A regular and marked increase of hearing acuity at frequencies of 12, 16, and 20 kHz, by both air and bone conduction, is found in patients with bronchial asthma.Laboratory of Pathophysiology and Acoustics, Moscow Research Institute of the Ear, Throat, and Nose, Ministry of Health of the RSFSR. Department of Pulmonology, S. P. Botkin Hospital, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR A. D. Ado.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 82, No. 9, pp. 1050–1051, September, 1976.     

Further evidence for linkage of low-mid frequency hearing impairment to the candidate region on chromosome 4p16.3

We have investigated a three-generation family with an autosomal dominant low-mid frequency hearing loss. Audiograms show consistently a hearing threshold of 50+/-20 db hearing loss (HL) between 250 Hz and 1-2 kHz. Normal hearing level was reached between 3 and 6 kHz in all examined children. Adult patients show an additional hearing impairment (HI) in the mid and higher frequencies that seems to differ from presbyacusis. The HI is always bilateral and symmetrical. Genes causing non-syndromic autosomal-dominant deafness with HI in the low and mid frequencies were previously mapped to chromosome 4p16.3 (DFNA6, DFNA14) and chromosome 5q31 (DFNA1). After exclusion of linkage to DFNA1 on chromosome 5, we mapped the candidate gene region to the DFNA14 and DFNA6 loci, between the genetic markers D4S432 and D4S431, located on chromosome 4. This is a further family in which evident linkage of low-mid frequency HI to the candidate region on chromosome 4p16.3 has been found.     

A new family with the Townes-Brocks syndrome

We describe a new family with the Townes-Brocks syndrome, a dominantly inherited syndrome of anal, urorenal, ear and limb malformations. The proband shows the full spectrum of anomalies, including imperforate anus, prominent perineal raphe, rectoperineal fistula, triphalangeal thumb, preaxial hexadactyly, syndactyly, clinodactyly, preauricular protuberances, hypoplastic satyr ears, sensorineural hearing loss and urorenal anomalies. In contrast, the father shows only limb anomalies, sensorineural hearing loss and renal anomalies. Anorectal malformations, which are present in almost every patient with the Townes-Brocks syndrome, were absent in the father. This case report illustrates the intrafamilial variability of the Townes-Brocks syndrome. Consequently, careful examination of relatives of patients with this syndrome is necessary for the differential diagnosis with the sporadically inherited VA(C)TER(L) association.     

An exploration of how health care professionals understand experiences of deafness

Findings from recent deaf education intervention programmes with health care professionals emphasise the importance of sociocultural dimensions of medicine, pointing to the need to further investigate health professionals’ current understandings of deafness. Situated within a social constructionist and critical realist framework, we investigated health professionals’ understandings of deafness and experiences of providing health services in Australia to d/Deaf people. Through an inductive thematic analysis of 18 individual interviews with medical or allied health professionals, we identified an overarching theme we labelled hearingness as privileged, whereby professionals accounted for the quality of the health services available to d/Deaf people in Australia. The professionals recognised the services as not good enough and, through relating their efforts to do the best they can, and describing how the situation could always be better, it was evident that the professionals were negotiating a larger health system that disadvantages the needs of d/Deaf people for the needs of people with hearingness. We discuss the implications of working within a system that privileges hearingness.     

天津市职业性噪声暴露人群健康状况及其影响因素

目的了解天津市职业性噪声暴露人群健康状况,分析其影响因素,为指导和实施干预措施提供科学依据。方法采用χ~2检验和Logistic回归分析对天津市11 643名职业性噪声暴露人群健康资料及所在288家企业工作场所噪声监测数据进行分析。结果天津市职业性噪声暴露人群高频听力损失检出率33.81%,高血压检出率19.81%,心电图异常检出率12.11%,男性高频听力损失明显高于女性。高噪声暴露组工人高频听力损失检出率、女性工人心电图异常率均高于低暴露组(P0.05);随噪声接触工龄延长,高频听力损失检出率增加(P0.05).Logistic回归结果表明,年龄增加、工龄延长和高噪声暴露均为高频听力损失的独立危险因素(OR1.00,P0.05);高噪声暴露情况下作业工人高频听力损失率增加42.00%(男性)和29.00%(女性),工龄每增加5年作业工人听力损失率增加23.00%(男性)和147.00%(女)。此外,高噪声暴露可增加男性高血压和女性心电图异常的发病风险(OR1.00,P0.05)。结论天津市职业性噪声暴露人群高频听力损失较为严重,高噪声暴露是高频听力损失、男性高血压发病和女性心电图异常的危险因素,应当引起重视,采取积极措施,预防疾病的发生。