Antinuclear antibodies in postinfectious smell loss - a pilot study

Abstract

Background: Numerous diseases are mediated by autoimmune mechanisms some of which have been shown to be associated with reduced olfactory function, e.g. systemic lupus erythematosus, Sjögren syndrome, psoriasis vulgaris. Postinfectious smell loss is a frequent cause of olfactory dysfunction. However, its nature is not fully understood, but connections to immune mediated processes might be possible. The primary aim of the present study was therefore to investigate the possible relation of postinfectious smell loss with autoimmune processes. Methods: Fifty-two patients (35 female, 17 male; mean age 57 years ± 12 years) with postinfectious smell loss and 56 controls (21 female, 35 male; mean age 58 years ± 13 years), with olfactory dysfunction of other causes (sinunasal, posttraumatic or idiopathic)were included in the present study. The patients' olfactory function was measured using the extended test battery of the "Sniffin' Sticks". Furthermore venous blood samples were taken and analyzed for antinuclear autoantibodies. Results:Patients showed anti-nuclear antibodies (ANA) significantly more frequently compared to controls, although ANAs were typically only present at cut off levels of 1:100. In addition, there was a significant association between the presence of ANAs and odor thresholds. Conclusions:Results from this study indicate that postinfectious olfactory dysfunction may be associated with autoimmune processes, as they show significantly more ANAs -although not at a clincially significant level -compared to patients with olfactory deficits of other origin.

Olfactory dysfunction after coronavirus disease 2019 (COVID‐19) vaccination

“…Although the mechanism is not understood, the immune response induced by vaccination might explain olfactory dysfunction. Wallitzec-Dworschak et al 4 suggested that postinfectious olfactory loss might be related to immune-mediated processes, asanti-nuclear antibodies were significantly more frequent in patients with olfactory dysfunction compared to controls. In addition, reduced olfactory function has already been shown in several autoimmune disorders, such as multiple sclerosis, pemphigus vulgaris, psoriasis vulgaris, and Sjögren syndrome.…”

“…In addition, reduced olfactory function has already been shown in several autoimmune disorders, such as multiple sclerosis, pemphigus vulgaris, psoriasis vulgaris, and Sjögren syndrome. 4 According to Farsalinos et al, 5 spike protein interacts locally with the alpha7 nicotinic acetylcholine receptors (nAChRs), deregulating the inflammatory reflex. 6 According to this hypothesis, spike protein, when expressed locally after vaccination, may interact with alpha7 nAChRs in macrophages.…”