A rare genomic duplication in 2p14 underlies autosomal dominant hearing loss DFNA58.

Here we define a ~200 Kb genomic duplication in 2p14 as the genetic signature that segregates with postlingual progressive sensorineural autosomal dominant hearing loss (HL) in 20 affected individuals from the DFNA58 family, first reported in 2009. The duplication includes two entire genes, PLEK and CNRIP1, and the first exon of PPP3R1 (protein coding), in addition to four uncharacterized long non-coding (lnc) RNA genes and part of a novel protein-coding gene. Quantitative analysis of mRNA expression in blood samples revealed selective overexpression of CNRIP1 and of two lncRNA genes (LOC107985892 and LOC102724389) in all affected members tested, but not in unaffected ones. Qualitative analysis of mRNA expression identified also fusion transcripts involving parts of PPP3R1, CNRIP1 and an intergenic region between PLEK and CNRIP1, in the blood of all carriers of the duplication, but were heterogeneous in nature. By in situ hybridization and immunofluorescence, we showed that Cnrip1, Plek and Ppp3r1 genes are all expressed in the adult mouse cochlea including the spiral ganglion neurons, suggesting changes in expression levels of these genes in the hearing organ could underlie the DFNA58 form of deafness. Our study highlights the value of studying rare genomic events leading to HL, such as copy number variations. Further studies will be required to determine which of these genes, either coding proteins or non-coding RNAs, is or are responsible for DFNA58 HL.

Post-acute sequelae of SARS-CoV-2 infection: relationship of central nervous system manifestations with physical disability and systemic inflammation.

BACKGROUND: Despite the multitude of clinical manifestations of post-acute sequelae of SARS-CoV-2 infection (PASC), studies applying statistical methods to directly investigate patterns of symptom co-occurrence and their biological correlates are scarce. METHODS: We assessed 30 symptoms pertaining to different organ systems in 749 adults (age = 55 ± 14 years; 47% female) during in-person visits conducted at 6-11 months after hospitalization due to coronavirus disease 2019 (COVID-19), including six psychiatric and cognitive manifestations. Symptom co-occurrence was initially investigated using exploratory factor analysis (EFA), and latent variable modeling was then conducted using Item Response Theory (IRT). We investigated associations of latent variable severity with objective indices of persistent physical disability, pulmonary and kidney dysfunction, and C-reactive protein and D-dimer blood levels, measured at the same follow-up assessment. RESULTS: The EFA extracted one factor, explaining 64.8% of variance; loadings were positive for all symptoms, and above 0.35 for 16 of them. The latent trait generated using IRT placed fatigue, psychiatric, and cognitive manifestations as the most discriminative symptoms (coefficients > 1.5, p < 0.001). Latent trait severity was associated with decreased body weight and poorer physical performance (coefficients > 0.240; p ⩽ 0.003), and elevated blood levels of C-reactive protein (coefficient = 0.378; 95% CI 0.215-0.541; p < 0.001) and D-dimer (coefficient = 0.412; 95% CI 0.123-0.702; p = 0.005). Results were similar after excluding subjects with pro-inflammatory comorbidities. CONCLUSIONS: Different symptoms that persist for several months after moderate or severe COVID-19 may unite within one latent trait of PASC. This trait is dominated by fatigue and psychiatric symptoms, and is associated with objective signs of physical disability and persistent systemic inflammation.

Noise Exposure and Distortion Product Otoacoustic Emission Suprathreshold Amplitudes: A Genome-Wide Association Study.

BACKGROUND: Although several candidate-gene association studies have been conducted to investigate noise-induced hearing loss (NIHL) in humans, most are underpowered, unreplicated, and account for only a fraction of the genetic risk. Mouse genome-wide association studies (GWASs) have revolutionized the field of genetics and have led to the discovery of hundreds of genes involved in complex traits. The hybrid mouse diversity panel (HMDP) is a collection of classic inbred and recombinant inbred strains whose genomes have been either genotyped at high resolution or sequenced. To further investigate the genetics of NIHL, we report the first GWAS based on distortion product otoacoustic emission (DPOAE) measurements and the HMDP. METHODS: A total of 102 strains (n = 635) from the HMDP were evaluated based on DPOAE suprathreshold amplitudes before and after noise exposure. DPOAE amplitude variation was set at 60 and 70 dB SPL of the primary tones for each frequency separately (8, 11.3, 16, 22.6, and 32 kHz). These values provided an indirect assessment of outer hair cell integrity. Six-week-old mice were exposed for 2 h to 10 kHz octave-band noise at 108 dB SPL. To perform local expression quantitative trait locus (eQTL) analysis, gene expression microarray profiles were generated using cochlear RNA from 64 hybrid mouse strains (n = 3 arrays per strain). RESULTS: Several new loci were identified and positional candidate-genes associated with NIHL were prioritized, especially after noise exposure (1 locus at baseline and 5 loci after exposure). A total of 35 candidate genes in these 6 loci were identified with at least 1 probe whose expression was regulated by a significant cis-eQTL in the cochlea. After careful analysis of the candidate genes based on cochlear gene expression, 2 candidate genes were prioritized: Eya1 (baseline) and Efr3a (post-exposure). DISCUSSION AND CONCLUSION: For the first time, an association analysis with correction for population structure was used to map several loci for hearing traits in inbred strains of mice based on DPOAE suprathreshold amplitudes before and after noise exposure. Our results identified a number of novel loci and candidate genes for susceptibility to NIHL, especially the Eya1 and Efr3a genes. Our findings validate the power of the HMDP for detecting NIHL susceptibility genes.

A Cell Junctional Protein Network Associated with Connexin-26.

GJB2 mutations are the leading cause of non-syndromic inherited hearing loss. GJB2 encodes connexin-26 (CX26), which is a connexin (CX) family protein expressed in cochlea, skin, liver, and brain, displaying short cytoplasmic N-termini and C-termini. We searched for CX26 C-terminus binding partners by affinity capture and identified 12 unique proteins associated with cell junctions or cytoskeleton (CGN, DAAM1, FLNB, GAPDH, HOMER2, MAP7, MAPRE2 (EB2), JUP, PTK2B, RAI14, TJP1, and VCL) by using mass spectrometry. We show that, similar to other CX family members, CX26 co-fractionates with TJP1, VCL, and EB2 (EB1 paralogue) as well as the membrane-associated protein ASS1. The adaptor protein CGN (cingulin) co-immuno-precipitates with CX26, ASS1, and TJP1. In addition, CGN co-immunoprecipitation with CX30, CX31, and CX43 indicates that CX association is independent on the CX C-terminus length or sequence. CX26, CGN, FLNB, and DAMM1 were shown to distribute to the organ of Corti and hepatocyte plasma membrane. In the mouse liver, CX26 and TJP1 co-localized at the plasma membrane. In conclusion, CX26 associates with components of other membrane junctions that integrate with the cytoskeleton.

Bone marrow stem cells in facial nerve regeneration from isolated stumps.

INTRODUCTION: Severe lesions in the facial nerve may have extensive axonal loss and leave isolated stumps that impose technical difficulties for nerve grafting. METHODS: We evaluated bone marrow stem cells (BMSC) in a silicone conduit for rat facial nerve regeneration from isolated stumps. Group A utilized empty silicone tubes; in groups B-D, the tube was filled with acellular gel; and, in groups C and D, undifferentiated BMSC (uBMSC) or Schwann-like cells differentiated from BMSC (dBMSC) were added, respectively. Compound muscle action potentials (CMAPs) were measured, and histology was evaluated. RESULTS: Groups C and D had the highest CMAP amplitudes. Group C had shorter CMAP durations than groups A, B, and D. Distal axonal number and density were increased in group C compared with groups A and B. CONCLUSIONS: Regeneration of the facial nerve was improved by both uBMSC and dBMSC in rats, yet uBMSC was associated with superior functional results.

Generation of four induced pluripotent stem cells lines from PBMC of the DFNA58 family members: Two hearing-impaired duplication carriers (USPi006-A e USPi007-A) and two normal-hearing noncarriers (USPi004-A and USPi005-A).

The DFNA58 locus contains a genomic duplication involving three protein-coding genes (CNRIP1, PLEK, and PPP3R1's exon 1) and other uncharacterized lncRNA genes (LOC101927723, LOC107985892 and LOC102724389). To clarify the role of these genes in hearing and precisely determine their role in hearing loss, four iPSC lines were generated from two carriers and two noncarriers of the duplication.

Clinical, sociodemographic and environmental factors impact post-COVID-19 syndrome.

Background: Sociodemographic and environmental factors are associated with incidence, severity, and mortality of COVID-19. However, little is known about the role of such factors in persisting symptoms among recovering patients. We designed a cohort study of hospitalized COVID-19 survivors to describe persistent symptoms and identify factors associated with post-COVID-19 syndrome. Methods: We included patients hospitalized between March to August 2020 who were alive six months after hospitalization. We collected individual and clinical characteristics during hospitalization and at follow-up assessed ten symptoms with standardized scales, 19 yes/no symptoms, a functional status and a quality-of-life scale and performed four clinical tests. We examined individual exposure to greenspace and air pollution and considered neighbourhood´s population density and socioeconomic conditions as contextual factors in multilevel regression analysis. Results: We included 749 patients with a median follow-up of 200 (IQR = 185-235) days, and 618 (83%) had at least one of the ten symptoms measured with scales. Pain (41%), fatigue (38%) and posttraumatic stress disorder (35%) were the most frequent. COVID-19 severity, comorbidities, BMI, female sex, younger age, and low socioeconomic position were associated with different symptoms. Exposure to ambient air pollution was associated with higher dyspnoea and fatigue scores and lower functional status. Conclusions: We identified a high frequency of persistent symptoms among COVID-19 survivors that were associated with clinical, sociodemographic, and environmental variables. These findings indicate that most patients recovering from COVID-19 will need post-discharge care, and an additional burden to health care systems, especially in LMICs, should be expected.

Impact of the COVID-19 Pandemic on Physicians Working in the Head and Neck Field.

Background With the COVID-19 pandemic, the clinical practice of physicians who work in the head and neck field in Brazil dropped dramatically. The sustained impact of the pandemic is not known. Methods An anonymous online survey was distributed to Brazilian otolaryngologists, head and neck surgeons, medical and radiation oncologists, asking about their clinical practice in the third to fourth months of the pandemic. Results The survey was completed by 446 specialists. About 40% reported reduction of more than 75% in outpatient care. A reduction of 90% to 100% in airway endoscopies was reported by 50% of the responders, and the same rate of reduction regarding surgeries (pediatric or nasosinusal) was reported by 80% of them. Family income decreased by 50%, and the psychological burden on physicians was considerable. The availability of personal protective equipment and safety precautions were limited, especially in the public sector. Conclusion COVID-19 is still impacting the head and neck field, and safety concerns may hinder the prompt resumption of elective care.

Retention of progenitor cell phenotype in otospheres from guinea pig and mouse cochlea.

BACKGROUND: Culturing otospheres from dissociated organ of Corti is an appropriate starting point aiming at the development of cell therapy for hair cell loss. Although guinea pigs have been widely used as an excellent experimental model for studying the biology of the inner ear, the mouse cochlea has been more suitable for yielding otospheres in vitro. The aim of this study was to compare conditions and outcomes of otosphere suspension cultures from dissociated organ of Corti of either mouse or guinea pig at postnatal day three (P3), and to evaluate the guinea pig as a potential cochlea donor for preclinical cell therapy. METHODS: Organs of Corti were surgically isolated from P3 guinea pig or mouse cochlea, dissociated and cultivated under non-adherent conditions. Cultures were maintained in serum-free DMEM:F12 medium, supplemented with epidermal growth factor (EGF) plus either basic fibroblast growth factor (bFGF) or transforming growth factor alpha (TGFα). Immunofluorescence assays were conducted for phenotype characterization. RESULTS: The TGFα group presented a number of spheres significantly higher than the bFGF group. Although mouse cultures yielded more cells per sphere than guinea pig cultures, sox2 and nestin distributed similarly in otosphere cells from both organisms. We present evidence that otospheres retain properties of inner ear progenitor cells such as self-renewal, proliferation, and differentiation into hair cells or supporting cells. CONCLUSIONS: Dissociated guinea pig cochlea produced otospheres in vitro, expressing sox2 and nestin similarly to mouse otospheres. Our data is supporting evidence for the presence of inner ear progenitor cells in the postnatal guinea pig. However, there is limited viability for these cells in neonatal guinea pig cochlea when compared to the differentiation potential observed for the mouse organ of Corti at the same developmental stage.

Partial lesions of the intratemporal segment of the facial nerve: graft versus partial reconstruction.

OBJECTIVES: In cases of partial lesions of the intratemporal segment of the facial nerve, should the surgeon perform an intraoperative partial reconstruction, or partially remove the injured segment and place a graft? We present results from partial lesion reconstruction on the intratemporal segment of the facial nerve. METHODS: A retrospective study on 42 patients who presented partial lesions on the intratemporal segment of the facial nerve was performed between 1988 and 2005. The patients were divided into 3 groups based on the procedure used: interposition of the partial graft on the injured area of the nerve (group 1; 12 patients); keeping the preserved part and performing tubulization (group 2; 8 patients); and dividing the parts of the injured nerve (proximal and distal) and placing a total graft of the sural nerve (group 3; 22 patients). RESULTS: Fracture of the temporal bone was the most frequent cause of the lesion in all groups, followed by iatrogenic causes (p < 0.005). Those who obtained results lower than or equal to III on the House-Brackmann scale were 1 (8.3%) of the patients in group 1, none (0.0%) of the patients in group 2, and 15 (68.2%) of the patients in group 3 (p <0.001). CONCLUSIONS: The best surgical technique for therapy of a partial lesion of the facial nerve is still questionable. Among these 42 patients, the best results were those from the total graft of the facial nerve.

Overcoming developing-world challenges in cochlear implantation: a South American perspective.

PURPOSE OF REVIEW: Effective hearing rehabilitation with cochlear implantation is challenging in developing countries, and this review focuses on strategies for childhood profound sensorineural hearing loss care in South America. RECENT FINDINGS: Most global hearing loss exists in developing countries; optimal cost-effective management strategies are essential in these environments. This review aims to assess and discuss the challenges of cochlear implantation effectiveness in South America. The authors searched electronic databases, bibliographies, and references for published and unpublished studies. Sensitivity analysis was performed to evaluate the effect of device cost, professional salaries, annual number of implants, and failure rate. Costs were obtained from experts in South America using known costs and estimations whenever necessary. Recent studies reported several challenges in unilateral or bilateral cochlear implants: cochlear implant costs, deaf education costs, increasing need for cochlear implant capacity, and training and increasing longevity. SUMMARY: Cochlear implantation was very cost-effective in all South American countries. Despite inconsistencies in the quality of available evidence, the robustness of systematic review methods substantiates the positive findings of the included studies, demonstrating that unilateral cochlear implantation is clinically effective and likely to be cost-effective in developing countries.

Validation of a Portuguese version of the health-related quality of life measure for active chronic otitis media (COMQ-12).

INTRODUCTION: Measuring the impact on quality of life, especially after the beginning of the treatment, is becoming increasingly important in healthcare. OBJECTIVE: The aim of this study was to translate the Chronic Otitis Media Questionnaire-12 (COMQ-12) into Portuguese language and validate this version in a group of patients with chronic otitis media. METHODS: The Portuguese version of COMQ-12 was obtained by translation and back translation. Portuguese speaking patients with a history of active chronic otitis media were asked to complete the COMQ-12 Portuguese version. Cronbach's α coefficient was calculated for an estimation of the internal consistency of the questionnaire. RESULTS: A total of 100 patients were included in the study; 49 women and 51 men, with a mean age of 39 years (range 12-77 years, median 40 years). The average COMQ-12 score was 29, out of a maximum score of 60. Cronbach's α result for the Portuguese version of the COMQ-12 was 0.85, indicating a high internal consistency. The participants presented with different forms of chronic otitis media, and almost all domains of the COMQ-12 questionnaire were able to differentiate between patients with healed chronic otitis media and patients with cholesteatoma or wet tympanic membrane perforation. Showing that patients with healed chronic otitis media have a better quality of life, measured by the COMQ-12, is a first step to guarantee the questionnaire's validity. The next step will consist on routinely using the questionnaire in patients undergoing surgery for chronic otitis media in order to evaluate their quality of life after treatment. CONCLUSION: The COMQ-12 Portuguese version showed high reliability, and may be used as an assessment of quality of life in patients with chronic otitis media.

Healing of subacute tympanic membrane perforations in chinchillas treated with epidermal growth factor and pentoxifylline.

HYPOTHESIS: The aims of the present study were to determine the effect of epidermal growth factor (EGF) and pentoxifylline on subacute tympanic membrane (TM) perforations and to quantify the healing rate of such perforations treated with these drugs alone or in combination. BACKGROUND: It is known that EGF modulates in vitro and in vivo proliferation of epithelial and endothelial cells. Pentoxifylline is a methylxanthine that has been used to treat experimental skin flaps and venous leg ulcers. Data in the literature regarding this subject are contradictory, and quantitative data regarding the effects of EGF and pentoxifylline on TM perforation healing are scarce. METHODS: We studied 50 chinchillas submitted to TM perforation. On postoperative Day 30, eight were selected for histologic analysis. Of the remaining 42, those presenting little or no healing were distributed into four groups: control, EGF, pentoxifylline, and EGF combined with pentoxifylline. RESULTS: Histologic analysis showed that the observation period adopted was sufficient to consider the TM perforations subacute. We found significant differences between the study groups and the control group in the healing rate of subacute TM perforations during a 30-day period (analysis of variance; p < 0.001), which was 30.3% for the EGF group, 3.6% for the pentoxifylline group, 16.5% for the EGF-pentoxifylline group, and 8.7% for the control group. CONCLUSIONS: The use of EGF promoted healing of subacute TM perforations in chinchillas, and the use of pentoxifylline did not. The combination of the two had no synergistic effect on the healing of these perforations.

Impact of the COVID-19 Pandemic on Physicians Working in the Head and Neck Field

Abstract Background With the COVID-19 pandemic, the clinical practice of physicians who work in the head and neck field in Brazil dropped dramatically. The sustained impact of the pandemic is not known. Methods An anonymous online survey was distributed to Brazilian otolaryngologists, head and neck surgeons, medical and radiation oncologists, asking about their clinical practice in the third to fourth months of the pandemic. Results The survey was completed by 446 specialists. About 40 % reported reduction of more than 75 % in outpatient care. A reduction of 90 % to 100 % in airway endoscopies was reported by 50 % of the responders, and the same rate of reduction regarding surgeries (pediatric or nasosinusal) was reported by 80 % of them. Family income decreased by 50 %, and the psychological burden on physicians was considerable. The availability of personal protective equipment and safety precautions were limited, especially in the public sector. Conclusion COVID-19 is still impacting the head and neck field, and safety concerns may hinder the prompt resumption of elective care.

Moving Beyond GDP: Cost Effectiveness of Cochlear Implantation and Deaf Education in Latin America.

HYPOTHESIS: Cochlear implantation (CI) and deaf education are cost effective management strategies of childhood profound sensorineural hearing loss in Latin America. BACKGROUND: CI has been widely established as cost effective in North America and Europe and is considered standard of care in those regions, yet cost effectiveness in other economic environments has not been explored. With 80% of the global hearing loss burden existing in low- and middle-income countries, developing cost effective management strategies in these settings is essential. This analysis represents the continuation of a global assessment of CI and deaf education cost effectiveness. METHODS: Brazil, Colombia, Ecuador, Guatemala, Paraguay, Trinidad and Tobago, and Venezuela participated in the study. A Disability Adjusted Life Years model was applied with 3% discounting and 10-year length of analysis. Experts from each country supplied cost estimates from known costs and published data. Sensitivity analysis was performed to evaluate the effect of device cost, professional salaries, annual number of implants, and probability of device failure. Cost effectiveness was determined using the World Health Organization standard of cost effectiveness ratio/gross domestic product per capita (CER/GDP)<3. RESULTS: Deaf education was very cost effective in all countries (CER/GDP 0.07-0.93). CI was cost effective in all countries (CER/GDP 0.69-2.96), with borderline cost effectiveness in the Guatemalan sensitivity analysis (Max CER/GDP 3.21). CONCLUSION: Both cochlear implantation and deaf education are widely cost effective in Latin America. In the lower-middle income economy of Guatemala, implant cost may have a larger impact. GDP is less influential in the middle- and high-income economies included in this study.

Vestibular rehabilitation therapy in children.

OBJECTIVES: Vestibular disturbances are underdiagnosed in children. However, balance impairment may compromise the normal development of affected children. The appropriate therapeutic approach has not been agreed on for this age group. Vestibular rehabilitation therapy has excellent results in adults, but very few data exist regarding its results in children. We evaluated through clinical assessment and computerized dynamic posturography the outcome of children with peripheral vestibular disturbances undergoing vestibular rehabilitation therapy and observed the influence of learning and of central nervous system maturation on posturography retest results. METHODS: Sixteen children (10 boys and 6 girls) with peripheral vestibular disorders (mean age, 8 yr 7 mo) constituted the cohort and were consecutively treated with vestibular rehabilitation therapy. Symptomatic children underwent pre- and posttreatment computerized dynamic posturography. Their outcome was clinically assessed. Another 16 asymptomatic children, paired by sex and age, underwent two computerized dynamic posturography procedures with the same time interval as that of the symptomatic group. RESULTS: All children completed the treatment. Total recovery of symptoms occurred in nine (56.3%) patients, whereas a dramatic partial recovery was observed in the remaining seven (43.7%) children. Posturography Conditions 5 and 6, the vestibular ratio of the sensory analysis, and the composite equilibrium score had a significant quantitative improvement after vestibular rehabilitation therapy. No adverse reactions occurred to the exercises. No statistically significant posturography changes were observed in the asymptomatic children. CONCLUSION: Vestibular rehabilitation therapy seems to be a safe and efficacious therapeutic option in children with peripheral vestibular disturbances.

Auditory brainstem response and otoacoustic emission assessment of hearing-impaired children of mothers who contracted rubella during pregnancy.

CONCLUSIONS: Based on the auditory brainstem response (ABR) results obtained in this study, the incidence of deafness in children whose mothers had rubella during pregnancy is high (29.5%), and deafness is profound in most cases (80%). Vaccinating women of childbearing age against rubella is essential to reduce the number of cases of childhood sensorineural hearing loss caused by gestational rubella. OBJECTIVE: It has been shown in the literature that, in Brazil, gestational rubella is responsible for approximately 21% of cases of deafness in children. The purpose of this study was to assess the incidence of deafness in children whose mothers had rubella during pregnancy. MATERIAL AND METHODS: Between February and July 2001, we conducted a prospective study assessing hearing status in 17 children (mean age 6 months). The mothers had serologically (ELISA) confirmed gestational rubella. We recorded ABRs and analysed distortion product otoacoustic emissions (DPOAEs). RESULTS: In 5 children (29.5%), ABRs revealed sensorineural hearing loss, which was moderate to severe in 1 (20%) and profound in 4 (80%). The hearing loss was bilateral in 3 children (60%) and asymmetrical in 4 (80%). Regarding DPOAEs, 7 children (41%) presented no response, and this occurred bilaterally in 4 (57%). All children with abnormal ABRs also presented abnormal DPOAEs. Two children with normal ABRs presented abnormal DPOAEs.

Caloric test as a predictor tool of postural control in CI users.

CONCLUSIONS: Balance was improved at 365 days after CI in all patients. Caloric test findings were important determinants of balance outcomes over a year after CI. Pre-operative vestibular assessment findings should be documented because postural recovery over time depends on this information. OBJECTIVE: To verify the importance of the caloric test as a pre-operative predictor tool of postural control after CI surgery. METHODS: Prospective observational study made with 24 post-lingual deafness patients who underwent unilateral CI surgery. Vestibular assessments: questionnaire assessing vertigo, caloric tests, rotary chair (RC) testing, and computerized dynamic posturography (CDP), were sequentially performed for all patients before and 60, 120, 180, and 365 days after CI. RESULTS: Thirteen patients (54.2%) reported dizziness before CI. At the end of the study, dizziness remained unchanged in one (7.7%) patient, ameliorated in 11 (84.6%), and worsened in one (7.7%). Baseline caloric tests identified 29.2% patients with normal reflexes, 33.3% with unilateral areflexia or hyporeflexia, 12.5% with bilateral hyporeflexia, and 25% with bilateral vestibular loss (BVL). Most patients exhibited objective improvements in postural stability. At 365 days, the CDP condition (particularly C5) and CS were higher for caloric tests responders at baseline than for those with BVL at baseline.

Sudden deafness and Lyme disease.

OBJECTIVES/HYPOTHESIS: Otolaryngological manifestations are common in Lyme disease, affecting up to 75% of patients. One of these symptoms is sudden deafness. Hearing loss has been frequently described in Lyme disease; on the other hand, titers seropositive for, the causal agent of this disease, have been found in almost 20% of cases of sudden deafness. No consensual information exists on the outcome of Borrelia-seropositive patients or on the importance of determining Borrelia antibody titers. The present study aimed to determine the prevalence of seropositivity for Borrelia in sudden deafness, describing clinical characteristics and outcomes. STUDY DESIGN: This was a prospective observational study. METHODS: Forty-seven consecutive patients with sudden deafness were enrolled in the study. Demographic data, the presence of tinnitus and vertigo, and low- and high-frequency pure-tone averages were recorded. The percentage of hearing recovery was determined. Data obtained from Borrelia-seropositive patients were described and compared with those from the seronegative group. RESULTS: Titers positive for antibodies were present in 21.3% of the cases. Seropositive and seronegative groups of patients were homogeneous concerning age, sex distribution, the presence of tinnitus and vertigo, and high- and low-frequency hearing thresholds. Hearing outcome was not significantly different between the groups of patients. CONCLUSIONS: No distinctive clinical characteristic was found between seropositive and seronegative subjects. The hearing outcome of treated Borrelia-seropositive patients was similar to that of the seronegative group.