Abstract Introduction: The nose and throat are areas of high viral load, which could place otolaryngologists at an even higher risk for COVID-19 than other health-care workers. Objective: To investigate the prevalence of antibodies against SARS-CoV-2 in otorhinolaryngologists in southern Brazil, its relationship to demographic data, professional practice and reported symptoms of COVID-19, and compare it with official data on other health-care workers of the state and the general population in the same period. Methods: In this cross-sectional multicenter study, otolaryngologists actively practicing officially registered in Rio Grande do Sul were screened for IgM and IgG antibodies against SARS-CoV-2 from August 1 to September 15, 2020. A questionnaire was also applied. Results: We screened 358 (80.1%) of 447 actively practicing otolaryngologists (195 [54.5%] male; mean [SD] age, 47.77 [13.57] years; range, 26-84 years). Twenty-three were positive for IgM and/or IgG (6.4%). This result was significantly associated with reports of infected household contacts (19/315 negatives and 8/23 positives; p<0.001). From 23 seropositive participants, 14 were asymptomatic (60.9%; p< 0.001). There were no significant associations between seroconversion and age, sex, number of patient appointments and surgical procedures, workplace (hospital or private practice), patients with or without respiratory symptoms, or level of personal protective equipment used. The rate of COVID-19 in all health-care workers in the state was 7.69% at the end of the same period. Data from state government seroprevalence was 5.26 (risk ratio [RR]; 95% CI 3.27–8.45) and 4.66 (RR; 95% CI 2.93–7.43) times higher in otolaryngologists than in the general population in August and September, respectively. Conclusion: Otolaryngologists had a higher seroconversion rate than the general population. Using personal protective equipment, the level of occupational exposure did not result in higher rates of infection than other health-care workers, but the presence of infected household contacts was associated with higher rates of seroconversion.

O hiperinsulinismo secundário à resistência periférica à insulina tem sido apontado como o fator etiológico mais frequente de síndromes tanto vestibulares como cocleares. OBJETIVO: Este estudo experimental registrou e analisou as alterações dos potenciais evocados auditivos através da eletrococleografia (ECoG) transtimpânica durante o hiperinsulinismo agudo induzido em um modelo animal. MATERIAL E MÉTODO: 6 ovelhas macho adultas foram divididas randomicamente em 2 grupos. Os animais submeteram-se ao exame de ECoG sob anestesia geral, e sangue periférico foi coletado para determinação de glicemia e hiperinsulinemia. Os animais do grupo intervenção (n=3) receberam insulina regular humana IV (0.1U/kG). O grupo controle (n=3) recebeu solução salina. Glicemia e insulinemia foram determinadas simultaneamente com o registro dos potenciais evocados a intervalos de 10 minutos, durante 90 minutos. RESULTADO: O grupo intervenção apresentou uma progressiva supressão da amplitude do potencial de ação quando comparado ao grupo controle (p=0.001). CONCLUSÃO: Os dados sugerem fortemente que o hiperinsulinismo agudo induzido suprime a atividade coclear. Os resultados podem ser atribuídos à perda da atividade da enzima Na+K+ATPase na estria vascular, levando à perda do potencial endococlear e da despolarização subsequente das células ciliadas assim como das células neurais que compõem a porção auditiva do VIII par craniano.

Hyperinsulinism secondary to peripheral insulin resistance has been described as the most frequent etiologic factor in cochlear and vestibular syndromes. AIM: This experimental study recorded and analyzed evoked auditory potential changes using transtympanic electrocochleography (EcochG) during induced acute hyperinsulinism in an animal model. MATERIALS AND METHODS: Six adult male sheep were randomly divided into 2 groups. The animals were submitted to EcochG under general anesthesia, and a peripheral blood sample was collected to measure glycemia and insulinemia. Animals in the intervention group (n=3) received regular human insulin IV (0.1 U/kg). The control group (n=3) received saline solution. Glycemia and insulinemia were measured simultaneously with the recording of evoked potentials at 10-minute intervals during 90 minutes. RESULTS: The intervention group experienced a progressive suppression in action potential amplitude when compared to the control group (p=0.001). CONCLUSION: Data strongly suggest that acute induced hyperinsulinism suppresses cochlear function. Results may be attributed to loss of Na+K+ATPase activity in the stria vascularis, leading to loss of endocochlear potential and subsequent depolarization of cochlear hair cells as well as of neural cells in the auditory portion of cranial nerve VIII.