Evaluation of the Incidence of Other Cranial Neuropathies in Patients With Postviral Olfactory Loss

Abstract

IMPORTANCE Postviral olfactory loss is a common cause of olfactory impairment, affecting both quality of life as well as overall patient mortality. It is currently unclear why some patients are able to recover fully after a loss while others experience permanent deficit. There is a lack of research on the possible association between postviral olfactory loss and other cranial neuropathies.OBJECTIVE To evaluate the incidence of other cranial nerve deficits in patients with postviral olfactory loss and determine if there is an association with neurologic injury in this group. This study also sought to determine if other known risk factors were associated with postviral olfactory loss. DESIGN, SETTING, AND PARTICIPANTSA case-control study was conducted at a tertiary care rhinology clinic from January 2015 to January 2018 to review the incidence of cranial neuropathies in 2 groups of patients, those with postviral olfactory loss and those with chronic rhinosinusitis without olfactory loss used as a control group.

Olfactory function in congenital cytomegalovirus infection: a prospective study

“…These findings contrast with an epidemiological study where a correlation was found between hearing loss and olfactory dysfunction, but infection, in particular congenital, was not considered as an influential factor [24]. The incidence of cranial neuropathies is higher in patients with post-viral olfactory loss compared to a control population [25]; however, we found no difference for the olfactory score between children presenting neurological manifestations and those without neurological involvement. These findings suggest that peripheral (audiovestibular) and central (cerebral) lesions are independent and that neurological damage did not induce vulnerability to olfactory dysfunction in our sCMV infants.…”

Coronaviruses and the Chemical Senses: Past, Present, and Future

“…Indeed, central processing pathways related to smell may be damaged through direct transmission of the virus to (Charles et al, 1995;Reiss et al, 1998;Doty, 2003;van Riel et al, 2015). Additionally, paresis/paralysis of the cranial nerves and history of neurological disease are associated with PVOD more than other olfactory disorders such as chronic rhinosinusitis (Jitaroon et al, 2020). Nevertheless, the decrease in sensory input leads to shrinkage of central olfactory areas such as the olfactory bulb that has both upstream and downstream effects (Mueller et al, 2005;Rombaux et al, 2006;Yao et al, 2018).…”

“…Reports show an abundance of nasal epithelial cells expressing cellular receptors and proteases needed for viral entry, i.e. angiotensin-converting enzyme 2 (ACE-2) and transmembrane serine protease 2 (TMPRSS2) ( (Brann et al, 2020;Chen et al, 2020;Gupta et al, 2020;Hoffmann et al, 2020;Sungnak et al, 2020) along with patients having neurological conditions to SARS-CoV-2 (Mao et al, 2020) and other infections leading to PVOD (Jitaroon et al, 2020). Although reports on OTDs in COVID-19 are being published or archived every day, the lack of follow-up studies to determine the dynamics of chemosensory changes in the disease and its reversibility over time are not currently available.…”

Central Nervous System Targets and Routes for SARS-CoV-2: Current Views and New Hypotheses

“…A second set of HCoVs are more pathogenic and include the etiological agents of the two epidemics occurring earlier this century, namely, the severe acute respiratory syndrome (SARS-CoV) and the Middle East respiratory syndrome (MERS-CoV) viruses. The ongoing outbreak of coronavirus disease 2019 (COVID- 19) completely different functions in the cell, to serve as binding partners. Binding of viruses to these adapted molecules, usually transmembrane enzymes, is the first step in viral infection.…”