RESUMO
X-linked hypophosphatemic rickets (XLH) is a genetic cause of renal hypophosphatemia due to inactivation of the PHEX gene, with an inappropriate concentration of fibroblast growth factor 23 (FGF23). Burosumab, an anti-FGF23 monoclonal antibody, is a validated treatment for XLH, but its use in patients with chronic kidney disease (CKD) has not been validated. A 61-year-old man with XLH developed CKD during follow-up. Conventional treatment (phosphate salts and active vitamin D analogs) was poorly tolerated. Treatment with burosumab was decided at a multi-professional meeting. Before burosumab initiation, his measured glomerular filtration rate was 44 mL/min/1.73 m2 defining CKD stage 3b and intact FGF23 concentration was very high (4496.0 ng/mL, N: 22.7-93.1) due to both XLH and CKD. Severe hypophosphatemia was observed after the two first injections of burosumab at usual doses (1 mg/kg monthly) and concomitant discontinuation of the conventional treatment. After increasing the dose and reducing the interval between doses (1.3 mg/kg every three weeks) from the third injection, serum phosphate concentration normalized and remained around the lower limit of the normal range. A local cutaneous reaction was observed just after the second injection, but did not recur. We report for the first time the efficacy and good short-term tolerance of burosumab in a patient with XLH and CKD, subject to a higher dosage aimed at achieving a phosphatemia at the lower limit of the normal range.
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Anticorpos Monoclonais Humanizados , Raquitismo Hipofosfatêmico Familiar , Hipofosfatemia , Insuficiência Renal Crônica , Masculino , Adulto , Humanos , Pessoa de Meia-Idade , Raquitismo Hipofosfatêmico Familiar/genética , Fatores de Crescimento de Fibroblastos/metabolismo , Fosfatos , Hipofosfatemia/tratamento farmacológico , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/tratamento farmacológicoRESUMO
PURPOSE: Hearing rehabilitation through middle ear surgery can be challenging, particularly for patients with chronic otitis media, but new hearing devices offer opportunity to reach this goal. The aim was to compare hearing outcomes and quality of life in patients who were converted from a Baha Attract system to the Osia system. METHODS: Prospective observational study, in which each subject acted as their own control. Six patients who were converted from a Baha Attract to an Osia system performed audiometric and quality of life assessments with different sound processor at fitting, 3, 6 and 12 months. The speech performance in noise with the Osia system at 12 months, expressed as dB SNR, was compared to the baseline condition (Baha 5). RESULTS: The PTA4 hearing thresholds improved from 42.6 ± 11 with Baha 5 Power to 34.8 ± 13.3 with Baha 5 SuperPower and to 25.4 ± 3.5 with the Osia at 12 months, leading to a significant functional gain of 17.2 ± 10.9 dB vs Baha 5 (p < 0.02). Speech understanding in both quiet and noise was clinically improved reaching a mean SNR of less than 1 dB at 12 months with the Osia system. Quality of life outcomes improved by more than 20% at 12-month follow-up. CONCLUSION: Aided hearing thresholds and speech understanding in noise improved when patients were converted from the Baha Attract system to the Osia system. The aided hearing threshold was maintained up to 8 kHz (26 dB) with the Osia system.
Assuntos
Auxiliares de Audição , Percepção da Fala , Humanos , Condução Óssea , Estudos Prospectivos , Qualidade de Vida , Audição , Perda Auditiva Condutiva/cirurgiaRESUMO
Congenital cytomegalovirus (CMV) infection leads to olfactory bulb lesions in the fetus, yet little is known about its impact on olfaction after birth. Here, we have assessed in a prospective study conducted on children in two French hospitals from 2016 to 2019, infection severity and olfactory performance after congenital CMV infection. Children with congenital CMV infection aged 3 to 10 years and healthy controls (CTL) matched for age and sex to CMV children symptomatic at birth (sCMV) were enrolled. Olfactory discrimination was assessed using mono-odorants and binary mixtures. Data were analyzed for 54 children with PCR-confirmed congenital CMV infection, including 34 sCMV (median [IQR] age, 6 [5-8] years; 19 [55.9%] male), and 20 CMV asymptomatic at birth (aCMV, median [IQR] age, 4 [3-6] years; 12 [60.0%] male). sCMV were compared to 34 CTL children. Olfactory scores in CMV-infected children were independent from vestibular deficit and hearing loss. The olfactory score was efficient to discriminate between CTL and sCMV for children > 6 years (area under the receiver-operating characteristic curve (AUC, 0.85; P = 0.0006), but not for children < 7 years. For children > 6 years, the proportion of children with total olfactory score < 4 differed between sCMV and CTL groups (91.2% and 18.7%, P < 0.001), but not between aCMV and age-matched healthy control groups. Conclusion: Congenital CMV infection is associated with reduced olfactory performance in children with infection symptoms at birth. Clinical trial registration: NCT02782988 (registration date: May 26, 2016). What is Known: â¢Congenital cytomegalovirus infection leads to olfactory bulb lesions in the fetus, yet little is known about its impact on olfaction after birth. â¢Depending on neonatal clinical presentation, children are either categorized as having a symptomatic or asymptomatic infection at birth. What is New: â¢Congenital cytomegalovirus infection is associated with reduced olfactory performance in children with infection symptoms at birth.
Assuntos
Infecções por Citomegalovirus , Criança , Pré-Escolar , Infecções por Citomegalovirus/complicações , Infecções por Citomegalovirus/congênito , Feminino , Humanos , Recém-Nascido , Masculino , Estudos ProspectivosRESUMO
Polycystic kidney diseases (PKDs) are genetic disorders that can cause renal failure and death in children and adults. Lowering cAMP in cystic tissues through the inhibition of the type-2 vasopressin receptor (V2R) constitutes a validated strategy to reduce disease progression. We identified a peptide from green mamba venom that exhibits nanomolar affinity for the V2R without any activity on 155 other G-protein-coupled receptors or on 15 ionic channels. Mambaquaretin-1 is a full antagonist of the V2R activation pathways studied: cAMP production, beta-arrestin interaction, and MAP kinase activity. This peptide adopts the Kunitz fold known to mostly act on potassium channels and serine proteases. Mambaquaretin-1 interacts selectively with the V2R through its first loop, in the same manner that aprotinin inhibits trypsin. Injected in mice, mambaquaretin-1 increases in a dose-dependent manner urine outflow with concomitant reduction of urine osmolality, indicating a purely aquaretic effect associated with the in vivo blockade of V2R. CD1-pcy/pcy mice, a juvenile model of PKD, daily treated with 13 [Formula: see text]g of mambaquaretin-1 for 99 d, developed less abundant (by 33%) and smaller (by 47%) cysts than control mice. Neither tachyphylaxis nor apparent toxicity has been noted. Mambaquaretin-1 represents a promising therapeutic agent against PKDs.
Assuntos
Antagonistas dos Receptores de Hormônios Antidiuréticos/farmacologia , Dendroaspis , Peptídeos Natriuréticos/farmacologia , Peptídeos/farmacologia , Doenças Renais Policísticas/tratamento farmacológico , Receptores de Vasopressinas/genética , Venenos de Serpentes/farmacologia , Animais , Benzazepinas/farmacologia , Células CHO , Cricetinae , Cricetulus , Cristalografia por Raios X , AMP Cíclico/metabolismo , Feminino , Células HEK293 , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Doenças Renais Policísticas/metabolismo , Transdução de Sinais , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Fatores de Tempo , Tolvaptan , Tripsina/químicaRESUMO
We present the case of a woman referred to our department at 34 weeks of pregnancy with a fetal ultrasonographic scan showing a mass that had developed within the right maxilla with invasion of the orbit. A retrospective examination showed that this tumor had been present since the 12th week of pregnancy. At 39+4 weeks of gestation, a boy was born. He presented a black firm aspect in the maxilla. A computed tomographic scan and magnetic resonance imaging revealed a soft tissue swelling over the right maxilla, extending into the orbit but without invasion of the globe. Surgical biopsy confirmed a melanotic neuroectodermal tumor of infancy. The pathologic examination did not show any neuroblast-like component on the hematoxylin eosin saffron staining. Because of the extension and the size of the lesion, neoadjuvant chemotherapy was carried out. At day 21, the patient received 1 cycle of low-dose cyclophosphamide and vincristine, 2 cycles of etoposide and carboplatin, and thereafter 1 cycle of cyclophosphamide, adriamycin, and vincristin because the lesion kept growing. After stabilization of the size of the tumor, at 4 months, a maxillectomy and partial resection of the orbital floor and lateral orbital wall was performed on the patient. As a complete resection would have required orbital exenteration, surgery was performed deliberately incomplete leaving a macroscopic residue (R2). At 2.5 years of follow-up, the patient showed complete remission with no lesions evident on magnetic resonance imaging.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Doenças Fetais/terapia , Doenças do Recém-Nascido/terapia , Tumor Neuroectodérmico Melanótico/terapia , Neoplasias Orbitárias/terapia , Adulto , Carboplatina/administração & dosagem , Ciclofosfamida/administração & dosagem , Doxorrubicina/administração & dosagem , Etoposídeo/administração & dosagem , Feminino , Doenças Fetais/diagnóstico por imagem , Doenças Fetais/patologia , Humanos , Recém-Nascido , Doenças do Recém-Nascido/diagnóstico por imagem , Doenças do Recém-Nascido/patologia , Masculino , Tumor Neuroectodérmico Melanótico/diagnóstico por imagem , Tumor Neuroectodérmico Melanótico/patologia , Neoplasias Orbitárias/diagnóstico por imagem , Neoplasias Orbitárias/patologia , Gravidez , Vincristina/administração & dosagemRESUMO
BACKGROUND: Bone conduction implants based on abutment-driven acoustic transmission result in good hearing outcomes; however, skin complications impact the quality of life (QOL) and possibly the viability of the device for many patients. The transcutaneous magnetic Baha® Attract technology was developed with the goal of minimising skin complications. OBJECTIVES: To analyse surgical, auditory and QOL outcomes for patients implanted with the Baha® Attract. DESIGN: Prospective multicentre cohort study. SETTING: Four French tertiary referral centres. PARTICIPANTS: Thirty-two patients implanted with the Baha® Attract, including 25 with conductive and mixed hearing loss and 7 with single-sided deafness. MAIN OUTCOME MEASURES: Postoperative follow-up involved the visual analysis of soft tissue adaptation and sound processor magnet strength measurement. The audiometric outcomes were evaluated in quiet and noise, and the QOL was assessed using three different questionnaires. RESULTS: After 12 months of use, soft tissue was thinner, and mean magnet strength was significantly decreased (3.7-3.1, P < 0.05) relative to measures during surgery. The speech recognition threshold in quiet significantly improved compared to unaided situation (73-44 dB HL respectively, P < 0.001) as did functional gain in noise (+2.8). All QOL scores improved, and the APHAB questionnaire score correlated with the audiometric outcomes. CONCLUSIONS: The Baha® Attract technology results in significant hearing gain and improves QOL. Skin complications were not observed, although surgeons, audiologists and patients should be aware of soft tissue evolution during the first postoperative year. The reversibility of this implant is a major advantage that allows switching to another system if hearing degrades.
Assuntos
Condução Óssea/fisiologia , Auxiliares de Audição , Perda Auditiva Condutiva/cirurgia , Audição/fisiologia , Próteses e Implantes , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Audiometria , Criança , Feminino , Seguimentos , Perda Auditiva Condutiva/fisiopatologia , Testes Auditivos , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Otológicos/métodos , Estudos Prospectivos , Desenho de Prótese , Qualidade de Vida , Percepção da Fala/fisiologia , Inquéritos e Questionários , Adulto JovemRESUMO
Menière's disease, clinically characterized by fluctuating, recurrent, and invalidating vertigo, hearing loss, and tinnitus, is linked to an increase in endolymph volume, the so-called endolymphatic hydrops. Since dysregulation of water transport could account for the generation of this hydrops, we investigated the role of aquaporin 3 (AQP3) in water transport into endolymph, the K-rich, hyperosmotic fluid that bathes the apical ciliated membrane of sensory cells, and we studied the regulatory effect of dexamethasone upon AQP3 expression and water fluxes. The different AQP subtypes were identified in inner ear by RT-PCR. AQP3 was localized in human utricle and mouse inner ear by immunohistochemistry and confocal microscopy. Unidirectional transepithelial water fluxes were studied by means of (3)H2O transport in murine EC5v vestibular cells cultured on filters, treated or not with dexamethasone (10(-7) M). The stimulatory effect of dexamethasone upon AQP3 expression was assessed in EC5v cells and in vivo in mice. AQP3 was unambiguously detected in human utricle and was highly expressed in both endolymph secretory structures of the mouse inner ear, and EC5v cells. We demonstrated that water reabsorption, from the apical (endolymphatic) to the basolateral (perilymphatic) compartments, was stimulated by dexamethasone in EC5v cells. This was accompanied by a glucocorticoid-dependent increase in AQP3 expression at both messenger RNA (mRNA) and protein level, presumably through glucocorticoid receptor-mediated AQP3 transcriptional activation. We show that glucocorticoids enhance AQP3 expression in human inner ear and stimulate endolymphatic water reabsorption. These findings should encourage further clinical trials evaluating glucocorticoids efficacy in Menière's disease.
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Aquaporina 3/biossíntese , Orelha Interna/efeitos dos fármacos , Endolinfa/metabolismo , Glucocorticoides/farmacologia , Água/metabolismo , Adsorção , Animais , Aquaporina 3/efeitos dos fármacos , Western Blotting , Células Cultivadas , Dexametasona/farmacologia , Orelha Interna/metabolismo , Endolinfa/efeitos dos fármacos , Humanos , Imuno-Histoquímica , Camundongos , Microscopia Confocal , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
BACKGROUND: The main clinical features of pseudohypoparathyroidism (PHP)/inactivating parathyroid hormone/parathyroid hormone-related protein signaling disorders (iPPSD), including parathyroid hormone (PTH) resistance, brachydactyly and short stature, develop during middle and late childhood. Very few studies have addressed hearing loss in PHP/iPPSD patients, and these studies have yielded widely divergent conclusions. The aim of our study was to assess hearing and determine the predictive factors of hearing loss in patients with PHP/iPPSD. METHODS: Our retrospective cohort study was conducted between March 2019 and May 2020 in the Otolaryngology Department and the calcium phosphate reference center for rare diseases in Bicêtre Paris-Saclay Hospital, France. We retrospectively collected data from patients with PHP/iPPSDs (age, sex, genetic mutations, height, body mass index (BMI), PTH resistance, presence or absence of ectopic ossifications and brachydactyly). All patients underwent auditory investigations, including tonal and vocal audiometry. The primary outcome was the pure tone average (PTA). The PTA was compared with the norm according to the International Organization for Standardization. Hearing loss was defined as a PTA ≥ 20 db. RESULTS: The median age of the patients was 15.6 years [9.5, 28.5]. Thirty-six patients were diagnosed with iPPSD2, and eight were diagnosed with iPPSD3. Twenty-six of them (59%) were female. Hearing impairment was confirmed in 17 patients (39%). The mean PTA and the mean SRT of the deaf ears were 40 ± 26 db and 31 ± 14 db. The mean difference in the PTA between the patients and the normal controls was 11.4 db (p = 0.00002). Short stature and the presence of ectopic ossifications were two significant predictive factors of hearing loss (p = 0.009 and p = 0.03, respectively). Sex, BMI, PTH resistance, mutation category and brachydactyly were not associated with an increased risk of hearing loss (p = 0.19, p = 0.41, p = 0.13, p = 0.50, p = 0.19, respectively). CONCLUSION: Our study confirmed the frequency of hearing loss in patients with PHP/iPPSD disease (prevalence = 39%). A diagnosis of PHP/iPPSD should trigger auditory investigations and follow-up, especially when short stature and/or ectopic ossifications are present.
Assuntos
Perda Auditiva , Pseudo-Hipoparatireoidismo , Humanos , Feminino , Pseudo-Hipoparatireoidismo/epidemiologia , Masculino , Estudos Retrospectivos , Perda Auditiva/epidemiologia , Prevalência , Adulto , Adolescente , Adulto Jovem , Criança , Hormônio Paratireóideo/sangue , Hormônio Paratireóideo/metabolismoRESUMO
BACKGROUND: Among all studies describing COVID-19 clinical features during the first wave of the pandemic, only a few retrospective studies have assessed the correlation between olfac-tory dysfunction (OD) and the evolution of disease severity. The main aim was to assess whether OD is a predictive factor of COVID-19 severity based on the patient's medical management (outpa-tient care, standard hospital admission, and ICU admission). METHODS: A national, prospective, mul-ticenter cohort study was conducted in 20 public hospitals and a public center for COVID-19 screen-ing. During the first wave of the pandemic, from 6 April to 11 May 2020, all patients tested positive for COVID-19 confirmed by RT-PCR underwent two follow-up ENT consultations within 10 days of symptom onset. The main outcome measures were the evolution of medical management (out-patient care, standard hospital admission, and ICU admission) at diagnosis and along the clinical course of COVID-19 disease. RESULTS: Among 481 patients included, the prevalence of OD was 60.7%, and it affected mostly female patients (74.3%) under 65 years old (92.5%), with fewer comor-bidities than patients with normal olfactory function. Here, 99.3% (290/292) of patients with OD presented with non-severe COVID-19 disease. Patients reporting OD were significantly less hospi-talized than the ones managed as outpatients, in either a standard medical unit or an ICU. Conclu-sions: As regards the clinical course of COVID-19 disease, OD could predict a decreased risk of hospitalization during the first wave of the pandemic.
RESUMO
BACKGROUND: Primary ciliary dyskinesia (PCD) is a rare genetic disorder characterised by pulmonary, otological and sino-nasal manifestations. Well-defined clinical outcome measures are needed in such rare diseases research to improve follow-up and treatments. Pulmonary outcome measures have recently been described. The aim of this study was to identify ear and upper airway outcome measures that could be used for longitudinal follow-up of individuals with PCD. METHODS: A scoping review was performed by systematically searching MEDLINE, Embase and Cochrane Database of Systematic Reviews online databases for studies published from January 1996 to March 2022 that included at least 10 adult or paediatric PCD patients and reported ear and upper airway outcomes. RESULTS: 33 studies (1794 patients) were included. 10 ear and upper airway outcomes were reported. 17 studies reported audiometry, 16 reported otoscopic findings, and 13 reported rhinoscopic findings and sinus imaging. Health-related quality of life questionnaires were performed in seven studies. There was a high variability in definitions and measurement of outcomes between studies. CONCLUSIONS: This scoping review highlights the lack of data regarding ear and upper airway outcomes in PCD. It also reports a high heterogeneity in outcome definitions or measures. We provide well-founded specific suggestions to standardise ear and upper airway outcome definitions and reporting for future PCD research studies.
Assuntos
Transtornos da Motilidade Ciliar , Qualidade de Vida , Adulto , Humanos , Criança , Revisões Sistemáticas como Assunto , Doenças RarasRESUMO
Primary ciliary dyskinesia (PCD) is a rare genetical disease characterized by an abnormal structure or function of the cilia, causing sinusitis, otitis, and bronchiectasis. Hearing loss affects 60% of PCD patients, but data are lacking concerning hearing and temporal bone imaging in adults. Our aim was to describe clinical and radiological ear disease in adults with genetically confirmed PCD. Data were recorded from January 2018 to December 2019. PCD patients were compared with controls with bronchiectasis without PCD. Clinical examination included otomicroscopy and auditory tests. A temporal bone CT scan (TBCT) was systematically performed. Seventeen patients (34 ears) were included in each group. The eardrums were abnormal in 25 (74%) PCD ears versus 8 (24%) ears in the controls (p < 0.05). Conductive hearing loss was more frequent in the PCD group (24% vs. 12% in controls). TBCT were abnormal in 94% PCD patients vs. 32% in the controls (p < 0.05). The Main CT-scan images in PCD were middle ear inflammation (65%), mastoid condensation (62%), or ossicular anomalies (35%). With its excellent sensitivity, TBCT gives typical arguments for PCD diagnosis, adding otological signs to the usual sinus CT signs (hypoplasia, aplasia). Systematic TBCT could be useful in the initial evaluation of patients with suspicion of PCD.
Assuntos
Hipogonadismo/congênito , Síndrome de Kallmann/genética , Mutação , Fatores de Transcrição SOXE/genética , Adulto , Androgênios/uso terapêutico , Humanos , Hipogonadismo/sangue , Hipogonadismo/tratamento farmacológico , Síndrome de Kallmann/sangue , Síndrome de Kallmann/diagnóstico , Hormônio Luteinizante/sangue , Masculino , Tamanho do Órgão , Indução de Remissão , Testículo/patologia , Testosterona/uso terapêutico , Adulto JovemRESUMO
Auditory neuropathy is caused by the loss of afferent input to the brainstem via the components of the neural pathway comprising inner hair cells and the first order neurons of the spiral ganglion. Recent work has identified the synapse between cochlear primary afferent neurons and sensory hair cells as a particularly vulnerable component of this pathway. Loss of these synapses due to noise exposure or aging results in the pathology identified as hidden hearing loss, an initial stage of cochlear dysfunction that goes undetected in standard hearing tests. We show here that repulsive axonal guidance molecule a (RGMa) acts to prevent regrowth and synaptogenesis of peripheral auditory nerve fibers with inner hair cells. Treatment of noise-exposed animals with an anti-RGMa blocking antibody regenerated inner hair cell synapses and resulted in recovery of wave-I amplitude of the auditory brainstem response, indicating effective reversal of synaptopathy.
Assuntos
Proteínas Ligadas por GPI/antagonistas & inibidores , Perda Auditiva Provocada por Ruído/tratamento farmacológico , Proteínas do Tecido Nervoso/antagonistas & inibidores , Regeneração/efeitos dos fármacos , Estimulação Acústica/métodos , Animais , Limiar Auditivo , Cóclea/citologia , Cóclea/efeitos dos fármacos , Cóclea/patologia , Modelos Animais de Doenças , Feminino , Proteínas Ligadas por GPI/metabolismo , Células Ciliadas Auditivas Internas/efeitos dos fármacos , Perda Auditiva Provocada por Ruído/patologia , Humanos , Masculino , Camundongos , Proteínas do Tecido Nervoso/metabolismo , Sinapses/efeitos dos fármacos , Sinapses/patologiaRESUMO
PURPOSE: To examine the MRI diagnostic performance in the assessment of therapeutic response to burosumab in children with X-linked hypophosphatemia (XLH). DESIGN: Prospective longitudinal open cohort. PATIENTS: Seventeen children with XLH, average age of 10.2 ± 2.7 years, had a knee MRI at baseline and after 1 year of burosumab. INTERVENTION: Children received burosumab at an average dose of 1.4 ± 0.5 mg/kg during 1 year for the treatment of severe rickets (the target serum phosphate ≥ 1.2 mmol/L (≥3.7 mg/dL). The primary endpoint was the change from baseline to 12 months in rachitic lesions on knee MRI. Secondary endpoints were changes in biochemical parameters of phosphate and alkaline phosphatase (ALP). RESULTS: One year of treatment with burosumab significantly reduced radiological disease activity on knee MRI (by 44 ± 29% in the transverse extent of widening) which was accompanied by a significant reduction in biochemical activity, namely in serum ALP activity, by 28 ± 17%. Additionally, MRI parameters after 1 year of treatment with burosumab (the maximum width of medial physis at 12 months and the change from baseline in the maximum width of lateral physis) were associated with ALP activity at 12 months. CONCLUSION: We suggest that MRI is a valuable and quantitative tool to evaluate the therapeutic response to burosumab. MRI could be an excellent alternative to standard bone radiographs for evaluation of the rachitic lesions in a clinical setting avoiding repeated exposition to ionizing radiation.
Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Raquitismo Hipofosfatêmico Familiar/diagnóstico , Raquitismo Hipofosfatêmico Familiar/tratamento farmacológico , Adolescente , Adulto , Criança , Pré-Escolar , Estudos de Coortes , Feminino , França , Humanos , Lactente , Joelho/diagnóstico por imagem , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Valor Preditivo dos Testes , Prognóstico , Resultado do Tratamento , Adulto JovemRESUMO
Gitelman syndrome (GS) is a rare salt-losing tubulopathy caused by an inactivating mutation in the SLC12A3 gene, encoding the thiazide-sensitive sodium chloride cotransporter (NCC). Patients with GS frequently complain of vertigo, usually attributed to hypovolemia. Because NCC is also located in the endolymphatic sac, we hypothesized that patients with GS might have vestibular dysfunction. Between April 2013 and September 2016, 20 (22%) out of 90 patients followed at the reference center complained of vertigo in the absence of orthostatic hypotension. Sixteen of them were referred to an otology department for investigation of vestibular function. The vertigo was of short duration and triggered in half of them by head rotation. Seven patients (44%) had a vestibular syndrome. Vestibular syndrome was defined: (1) clinically, as nystagmus triggered by the head shaking test (n = 5); and/or (2) paraclinically, as an abnormal video head impulse test (n = 0), abnormal kinetic test (n = 4) and/or abnormal bithermal caloric test (n = 3). Five patients had associated auditory signs (tinnitus, aural fullness or hearing loss). In conclusion, we found a high frequency of vestibular disorder in GS patients suffering from vertigo, suggesting a role of NCC in the inner ear. Referent physicians of these patients should be aware of this extrarenal manifestation that requires specific investigations and treatment.
RESUMO
Limited data is available concerning the safety of active middle ear implants (AMEI) during Magnetic Resonance Imaging (MRI). Measurements in temporal bones are the gold standard for preclinical assessment of device safety. In this study the coupling stability of an actuator as used in a fully implantable AMEI was determined in temporal bones. Eleven temporal bones were implanted with the actuator according to the manufacturer's surgical guidelines. The actuator was coupled on the incus short process as recommended for sensorineural hearing loss. Temporal bones were exposed 10 times to the MRI magnetic field by entering the MRI suite in a clinically relevant way. Computed Tomography (CT) images were acquired before and after the experiment to investigate the risk of actuator dislocation. Based on the electrical impedance of the actuator, the loading of the actuator to the incus was confirmed. Relative actuator displacement was determined on the CT images by comparing the initial with the final actuator position in 3D space. Impedance curves were analyzed after each exposure to check the loading of the actuator to the ossicles. Analysis of CT images with a 0.30.6 mm in-plane resolution indicate no actuator displacement. The maximum detected change in impedance for all actuators was 8.43 Ω at the actuator's resonance frequency. Impedance curves measured when the actuator was retracted from the short process after the experiment still indicate the presence of a clear resonance peak. No actuator displacement or dislocation could be detected in the analysis of CT images and the measured impedance curves. Impedance curves obtained when the actuator was retracted from the incus short process still show a clear resonance peak, indicating the device is still functional after the MRI exposures.