Clinical features of patients who had two COVID-19 episodes: a European multicentre case series.

OBJECTIVE: To investigate the clinical features of patients who had two demonstrated coronavirus disease 2019 (COVID-19) episodes. METHODS: Data of patients with both COVID-19 episodes were recruited from 22 March to 27 December 2020. The following outcomes were studied: epidemiological, comorbidities, prevalence and severity of general and otolaryngological symptom, olfactory, aroma, and gustatory dysfunctions. A comparison between first and second episodes was performed. RESULTS: Forty-five patients reported having two confirmed COVID-19 episodes. The majority of patients had mild infections in both episodes. The second clinical episode was significantly similar to the first. The symptom duration of the second episode was shorter than the first. The occurrence of loss of smell was unpredictable from the first to the second episode. CONCLUSION: The recurrence of COVID-19 symptoms is associated with a similar clinical picture than the first episode in patients with initial mild-to-moderate COVID episode. The pathophysiological mechanisms underlying the development of second episode remain uncertain and may involve either true reinfection or virus reactivation from sanctuaries.

Is anosmia the price to pay in an immune-induced scorched-earth policy against COVID-19?

Since the outbreak of Coronavirus Disease 2019 (COVID-19), loss of smell has increasingly been reported as a frequent clinical sign. Understanding the underlying mechanism and the prognostic value of this symptom will help better manage patients. SARS-CoV-2, as SARS-CoV-1, may likely spread to the central nervous system (CNS) via the olfactory nerve, a known gateway for respiratory neurotropic viruses. We hypothesise that sudden loss of smell due to COVID-19 is the consequence of a protective host defence mechanism involving apoptosis of olfactory receptor neurons. Sacrificing smelling over neuroprotection is a logical strategy, even more so as olfaction is the only sense with the ability to regenerate in adults. Induced apoptosis of olfactory neurons has been shown in mice, successfully preventing neuroinvasion. On the other hand, adult olfactory neurogenesis has been shown to be regulated in part by the immune system, allowing to restore olfactory function. Understanding anosmia as part of a defence mechanism would support the concept of sudden anosmia as being a positive prognostic factor in the short term. Also, it may orient research to investigate the risk of future neurodegenerative disease linked to persisting coronavirus in neurons.

Interest of vestibular evaluation in sequentially implanted children: Preliminary results.

INTRODUCTION: An early acquired or congenital absence of sensory input of the vestibule will lead to severe delayed posturomotor milestones. Previous studies have proven modifications and even complete ipsilateral loss of vestibular function after unilateral cochlear implantation. The objective of this study was to evaluate whether sequential cochlear implantation has an impact on vestibular function. METHODS: Retrospective study from January 2012 to January 2015 including 26 patients. The first stage consisted of determining the vestibular status of 26 hearing impaired children who were candidates for a second cochlear implant. Three months after contralateral implantation, we reevaluated the vestibular function of the same patients. The vestibular evaluation consisted of multiple tests for canal and otolith function. A complete clinical vestibular evaluation was performed, including the head thrust test. This was followed by an instrumental assessment composed of the classic bicaloric test and vestibular evoked myogenic potentials testing with tone bursts. RESULTS: A high prevalence of vestibular dysfunction (69%) was found in our group of unilaterally implanted children. Three patients had a unique functional vestibule at the not yet implanted ear. Vestibular evoked myogenic potentials responses stayed present in 15 of the 19 patients with a VEMP-response before contralateral implantation. Results of the caloric test changed for 6 patients after contralateral implantation. CONCLUSIONS: After contralateral implantation, 37% of our patients manifested modifications of their vestibular status. Intrasubject comparison of bicaloric and vestibular evoked myogenic potentials testing before and after contralateral cochlear implantation showed that canal function was better preserved than saccular function. Seeing the high prevalence of vestibular dysfunction in our test group of unilateral implanted children, sequential implantation must be preceded by a vestibular assessment to prevent complete bilateral vestibular areflexia and its potential consequences. Presence of hyporeflexia at the yet-to-be implanted ear seems to be a situation particularly at risk.

Incidence of congenital CMV in children at a hearing rehabilitation center.

OBJECTIVE: To evaluate the incidence of children with congenital CMV (cCMV) infection in a hearing rehabilitation center. METHODOLOGY: This was a retrospective review of 309 children followed in a rehabilitation center for mild to total sensorineural hearing loss (SNHL). Seventy-five children had dried blood spots that we retrieved and retrospectively analyzed for the presence of CMV DNA by real time PCR. The children were born in Belgium after January 1996. The etiology of the SNHL was investigated for each child. RESULTS: The CMV DNA was detected in the dried blood spots for 8 of the 75 children tested (10.6%) by real time PCR. In three children, an alternative etiology of SNHL was suspected before the cCMV infection was diagnosed. CONCLUSIONS: The incidence of children infected with cCMV in a hearing rehabilitation center is high (10.6%). The detection of CMV DNA in dried blood spots is useful and improves the etiological diagnosis of SNHL.