Rubella in Sub-Saharan Africa and sensorineural hearing loss: a case control study.

BACKGROUND: Rubella infection can affect several organs and cause birth defects that are responsible for congenital rubella syndrome (CRS). Congenital hearing loss is the most common symptom of this syndrome, occurring in approximately 60% of CRS cases. Worldwide, over 100 000 babies are born with CRS every year. There is no specific treatment for rubella, but the disease is preventable by vaccination. Since 1969, the rubella vaccine has been implemented in many countries, but in Africa, only a few countries routinely immunize against rubella. The aim of this study was to estimate the rate of infection from the wild-type rubella virus in São Tomé and Príncipe by determining rubella seroprevalence with a DBS method. The goal of this study was to reinforce the need for implementation of the rubella vaccine in this country. As secondary objectives, the validation of a DBS method was first attempted and an association between seroprevalence and hearing loss was assessed. METHODS: We collected samples from individuals observed during humanitarian missions in São Tomé and Príncipe. All individuals underwent an audiometric evaluation, and a drop of blood was collected for the dried blood spot (DBS). We define two groups: the case group (individuals with unilateral or bilateral hearing loss (HL)) and the control group (individuals with two normal ears). Patients were excluded if they suffered from conductive HL, if they showed evidence of possible causes of HL, if they had developmental delay or if they refused to participate in the study. RESULTS: Among the 315 subjects, we found 64.1% individuals with IgG for the rubella virus, 32.1% without immunity for the rubella virus and 3.8% who were borderline. In the control group, 62.6% were positive for the rubella IgG, whereas in the case group, 72% were positive. Analyzing both groups, with ages ranging from 2 to 14 years of age and from 15 to 35 years of age, we found a seroprevalence of 50.3% to rubella in the younger group and 82.1% in the older group, with a significant difference between cases and control group noted within the younger patients (p = 0.025). CONCLUSIONS: Rubella is a disease that can be prevented. Rubella infections are still very common in São Tomé and Príncipe, and women of child-bearing age are still at risk for rubella infection during pregnancy, justifying the urgency of vaccination against rubella. A statistically significant association between the group of children under 14 years of age with HL and immunity for rubella was observed in this country, although this study did not allow us to establish a cause-effect relationship between rubella infection and SNHL.

Computed Tomography versus Sleep Endoscopy (DISE) to Predict the Effectiveness of Mandibular Advancement Devices in Adult Patients with Obstructive Sleep Apnea: A Protocol for Systematic Review.

Obstructive sleep apnea is a sleep disorder with a high prevalence in the world population. The mandibular advancement device is one of the options for treating obstructive sleep apnea. Neck computed tomography and drug-induced sleep endoscopy are complementary diagnostic tests that may help predict the effectiveness of mandibular advancement devices. This study aims to analyze the best method for predicting the effectiveness of mandibular advancement devices in the therapeutic approach to obstructive sleep apnea. PubMed, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), and Web of Science Core Collection databases will be comprehensively searched. We will include randomized clinical trials, non-randomized prospective or retrospective clinical studies, case controls, cohort studies, and case series. Two authors will independently conduct data extraction and assess the literature quality of the studies. The analysis of the included literature will be conducted by Revman 5.3 software. The outcomes that will be analyzed are craniofacial characteristics, cephalometric assessments, site and type of obstruction of the upper airway, mean values of the apnea-hypopnea index, and SaO2 verified in the initial and follow-up polysomnography. This study will provide reliable, evidence-based support for the clinical application of mandibular advancement devices for obstructive sleep apnea.

Upper airway assessment in obstructive sleep apnea patients: can computed tomography with lateral cephalometry replace drug-induced sleep endoscopy (DISE)?

OBJECTIVE: To evaluate the association between results from drug-induced sleep endoscopy (DISE) and computed tomography with lateral cephalometry (CTLC) of the pharynx in obstructive sleep apnea (OSA) patients, regarding the same anatomic level, in order to understand if CTLC could replace DISE in selected patients. STUDY DESIGN: Cross-sectional. SETTING: Tertiary hospital. METHODS: A total of 71 patients who attended the Sleep Medicine Consultation in the Otorhinolaryngology Department of Hospital CUF Tejo between 1.6.2019 and 30.9.2021, performed a polysomnographic sleep study and were elected to undergo DISE and CTLC of the pharynx for diagnostic purposes were selected. Obstructions at the same anatomic levels - tongue base, epiglottis and velum - were compared in both exams. RESULTS: Patients with reduction of epiglottis-pharynx space on CTLC had also a complete obstruction at epiglottis level on the VOTE classification of DISE (p = 0,027). Reduction of velum-pharynx space or tongue base-pharynx space were not related to complete obstruction of the velum (P = 0,623) or the tongue base (p = 0,594) found in DISE. Those with two or more space reductions had a tendency to multilevel obstruction observed in DISE (p = 0.089). CONCLUSION: When evaluating the obstruction level(s) of an OSA patient, efforts should be made to perform DISE, since CTLC measures, though regarding at the same structures, don´t correlate completely with obstructions observed in DISE.

A finite element model to predict the consequences of endolymphatic hydrops in the basilar membrane.

Ménière's disease is an inner ear disorder, associated with episodes of vertigo, fluctuant hearing loss, tinnitus, and aural fullness. Ménière's disease is associated with endolymphatic hydrops. Clinical evidences show that this disease is often incapacitating, negatively affecting the patients' everyday life. The pathogenesis of Ménière's disease is still not fully understood and remains unclear. Previous numerical studies available in the literature related with endolymphatic hydrops, are very scarce. The present work applies the finite element method to investigate the consequences of endolymphatic hydrops in the normal hearing, associated with the Ménière's disease. The obtained results for the steady state dynamics analysis are in accordance with clinical evidences. The results show that the basilar membrane is not affected in the same intensity along its length and that the lower frequencies are more affected by the endolymphatic hydrops. From a clinical point of view, this work shows the relationship between the increasing of the endolymphatic pressure and the development of hearing loss.

Differences in the genotype frequencies of genes related to blood pressure regulation - a comparative study between South-West Europe and Peri-equatorial Africa.

Background: Since the emergence of the genus Homo, hominids have occupied a wide variety of environments, facing different selective pressures. Objectives: The aim this study is to compare genotype frequencies between South-West Europe and Peri-equatorial Africa in genes potentially modulators of blood pressure. Methods: The analyzed sample consisted of 325 individuals from Portugal and 226 individuals from Africa (48 from Mozambique and 178 from São Tomé and Príncipe). The following genetic variants were analyzed: intron 4 VNTR in eNOS, rs1050829 in G6PD, -3.7kb α-thalassemic deletion in HBA, rs1800457 in CYB5R3, Hp 1/2 genotype/phenotype in Hp and intron 16 I/D in ACE. Results: Frequencies of genotypes with the 4a allele in eNOS (p<0.001), the G allele in G6PD (p<0.001), the α-3.7 kb in HBA (p <0.001), the C allele in the CYB5R3 (p<0.001) were higher in Peri-equatorial Africa. The Hp 1.1 genotype of Hp has a higher frequency in Peri-equatorial Africa (p=0.002). ACE shows no significant differences. Conclusion: Results show differences in five genetic variants. Conditions of extreme heat and humidity, characteristic of Peri-equatorial Africa, have been associated with increased sodium loss. This study suggests that selected compensatory mechanisms printed in the genome, are nowadays risk factors for hypertension in Peri-equatorial Africa.

[Stapedo-Vestibular Ankylosis: Retrospective Study of Five Cases in São Tomé e Príncipe]. / Anquilose Estapedo-Vestibular: Estudo Retrospetivo de Cinco Casos em São Tomé e Príncipe.

INTRODUCTION: Otosclerosis is a common form of conductive hearing loss characterized by abnormal bone remodeling exclusively in the otic capsule. The prevalence of otosclerosis varies in racial populations and is described as being rare in black African populations. In this paper we aim to report five cases of clinical, and surgically confirmed, otosclerosis in black individuals, in São Tomé and Príncipe. MATERIAL AND METHODS: Since February 2011, Ear, Nose and Throat consultations and surgeries specialty have been carried out at Dr. Ayres de Menezes Hospital in cooperation with the project 'Health for all'. A retrospective analysis was undertaken of the records of all patients subjected either to stapedectomy or partial stapedectomy until February 2014. Information regarding clinical presentation, audiometric data and surgery reports was recorded. RESULTS: Five adult patients underwent stapedectomy or partial stapedectomy. All of them presented with normal otoscopy, conductive or mixed hearing loss on audiogram and normal tympanometry with absent stapedial reflexes. None of the patients had signs of infection or history of head trauma. Three cases showed improvement in the air-bone gap after surgery. The other two were lost to follow-up. DISCUSSION: We documented and surgically confirmed five cases of clinical otosclerosis in this population. A thematic review was carried out and concluded that, despite being described as a rare event in this race, available literature on this topic is not enough to state that there is lower prevalence of otosclerosis amongst the African population. CONCLUSION: Even if not common, otosclerosis cannot be disregarded as a possible cause for conductive hearing loss among the population of São Tomé and Principe.

Introdução: A otosclerose é uma causa frequente de hipoacusia de condução caracterizada pela alteração da remodelação óssea localizada exclusivamente à cápsula ótica. Diferenças rácicas são evidentes na literatura e, ao contrário dos caucasianos, as descrições na população de origem africana são raras. Neste trabalho pretende-se reportar cinco casos observados, e cirurgicamente confirmados, de otosclerose em indivíduos de raça negra, em São Tomé e Príncipe. Material e Métodos: Desde fevereiro de 2011, efetuam-se consultas e cirurgias de Otorrinolaringologia no Hospital Ayres de Menezes, em São Tomé e Príncipe, inseridas no projeto 'Saúde para todos ­ Especialidades'. Neste trabalho realizou-se um estudo retrospetivo dos doentes submetidos a estapedotomia ou estapedectomia parcial durante estas missões até fevereiro de 2014. Recolheu-se informação relativa à apresentação clínica, resultados audiométricos e relatórios cirúrgicos. Resultados: Cinco doentes, adultos, foram submetidos a procedimento cirúrgico. Todos apresentavam otoscopia normal, ausência de história de traumatismo cranioencefálico ou quadro infecioso, audiograma com hipoacusia mista ou de condução e timpanograma tipo A, sem reflexos estapédicos. Em três doentes foi possível realizar audiograma pós-operatório, verificando-se melhoria do gap aero-ósseo. Discussão: Neste trabalho documentam-se cinco casos de otosclerose clínica, e cirurgicamente confirmada, na população negra de São Tomé e Príncipe. Efetuada uma revisão temática, constata-se que, apesar de a otosclerose ser considerada rara nesta raça, os dados disponíveis parecem insuficientes para determinar se, de facto, diferentes raças têm diferentes incidências da doença. Conclusão: Apesar de rara, a otosclerose não pode ser ignorada como uma possível causa de hipoacusia de condução em São Tomé e Príncipe.

Genetic Basis of Nonsyndromic Sensorineural Hearing Loss in the Sub-Saharan African Island Population of São Tomé and Príncipe: The Role of the DFNB1 Locus?

Hearing loss (HL) is a common condition with both genetic and environmental causes, and it greatly impacts global health. The prevalence of HL is reportedly higher in developing countries such as the Sub-Saharan African island of São Tomé and Príncipe, where the deaf community is estimated to be less than 1% of the population. We investigated the role of the DFNB1 locus (GJB2 and GJB6 genes) in the etiology of nonsyndromic sensorineural hearing loss (NSSHL) in São Tomé and Príncipe. A sample of 316 individuals, comprising 136 NSSHL patients (92 bilateral, 44 unilateral) and 180 controls, underwent a clinical and audiological examination. Sequencing of the GJB2 coding region and testing for the (GJB6-D13S1830) and del(GJB6-D13S1854) GJB6 deletions were performed. A total of 311 out of 316 individuals were successfully analyzed regarding the GJB2 and GJB6 genetic variations, respectively. The frequency of the GJB2 coding mutations in patients and controls was low. Some of those coding mutations are the most commonly found in Eurasian and Mediterranean populations and have also been identified in Portugal. None of the GJB6 deletions was present. The presence of certain coding variants in São Tomé and Príncipe suggests a non-Sub-Saharan genetic influx and supports the previously reported genetic influx from European (mainly Portuguese) ancestors. In summary, DFNB1 locus does not appear to be a major contributor to NSSHL in São Tomé and Príncipe. However, the presence of both pathogenic and likely pathogenic mutations in GJB2 suggests that GJB2-related NSSHL might still occur in this population, warranting further research on GJB2 testing in NSSHL cases.

Upper airway assessment in obstructive sleep apnea patients: can computed tomography with lateral cephalometry replace drug-induced sleep endoscopy (DISE)? / Evaluación de la vía aérea superior en pacientes con apnea obstructiva del sueño: ¿puede la tomografía computarizada con cefalometría lateral reemplazar endoscopia del sueño inducida por fármacos por fármacos?

Objective To evaluate the association between results from drug-induced sleep endoscopy (DISE) and computed tomography with lateral cephalometry (CTLC) of the pharynx in obstructive sleep apnea (OSA) patients, regarding the same anatomic level, in order to understand if CTLC could replace DISE in selected patients. Study design Cross-sectional. Setting Tertiary hospital. Methods A total of 71 patients who attended the Sleep Medicine Consultation in the Otorhinolaryngology Department of Hospital CUF Tejo between 1.6.2019 and 30.9.2021, performed a polysomnographic sleep study and were elected to undergo DISE and CTLC of the pharynx for diagnostic purposes were selected. Obstructions at the same anatomic levels – tongue base, epiglottis and velum - were compared in both exams. Results Patients with reduction of epiglottis-pharynx space on CTLC had also a complete obstruction at epiglottis level on the VOTE classification of DISE (p = 0,027). Reduction of velum-pharynx space or tongue base-pharynx space were not related to complete obstruction of the velum (P = 0,623) or the tongue base (p = 0,594) found in DISE. Those with two or more space reductions had a tendency to multilevel obstruction observed in DISE (p = 0.089). Conclusion When evaluating the obstruction level(s) of an OSA patient, efforts should be made to perform DISE, since CTLC measures, though regarding at the same structures, don´t correlate completely with obstructions observed in DISE. (AU)

Objetivo Evaluar la asociación entre los resultados de la endoscopia del sueño inducida por fármacos (DISE) y la tomografía computarizada con cefalometría lateral (TCCL) de faringe en pacientes con apnea obstructiva del sueño (AOS), en el mismo nivel anatómico, para comprender si la TCCL podría reemplazar DISE en pacientes seleccionados. Diseño del estudio Transversal. Lugar Hospital de tercer nivel. Métodos Un total de 71 pacientes que acudieron a la Consulta de Medicina del Sueño en el Servicio de Otorrinolaringología del Hospital CUF Tejo entre el 1.6.2019 y el 30.9.2021, a los que se les había realizado un estudio polisomnográfico del sueño y fueron elegidos para realizar DISE y TCCL de faringe con fines diagnósticos, fueron seleccionados. Las obstrucciones en los mismos niveles anatómicos (base de la lengua, epiglotis y velo) se compararon en ambos exámenes. Resultados Los pacientes con reducción del espacio epiglotis-faringe en TCCL también tenían una obstrucción completa a nivel de epiglotis en la clasificación VOTE de DISE (p = 0,027). La reducción del espacio velo-faringe o base de la lengua-faringe no se relacionó con la obstrucción completa del velo (P = 0,623) o de la base de la lengua (p = 0,594) encontrada en DISE. Aquellos con dos o más reducciones de espacio presentaron tendencia a la obstrucción multinivel observada en DISE (p = 0,089). Conclusión Al evaluar el o los niveles de obstrucción de un paciente con AOS, se debe intentar realizar DISE, ya que las medidas de TCCL, aunque se refieren a las mismas estructuras, no se correlacionan completamente con las obstrucciones observadas en DISE. (AU)