Objective olfactory testing in patients presenting with sudden onset olfactory dysfunction as the first manifestation of confirmed COVID-19 infection

Abstract

Background: The aims of this study are to investigate the COVID-19 status of patients with initial sudden olfactory anosmia (ISOA) using nasopharyngeal swabs for RT-PCR analysis and to explore their olfactory dysfunctions with psychophysical olfactory evaluation. Methodology: This prospective study included 78 ISOA patients who fulfilled a patient-reported outcome questionnaire and underwent a nasopharyngeal swabs. Among these, 46 patients performed psychophysical olfactory evaluation using sniffing tests. Based on the duration of the ISOA, two groups of patients were compared: patients with anosmia duration ≤12 days (group 1) and those with duration >12 days (group 2). Results: Among group 1, 42 patients (87.5%) had a positive viral load regarding RT-PCR while 6 patients (12.5%) were negative. In group 2, 7 patients (23%) had a positive viral load and 23 patients (77%) were negative. Among the 46 patients having performed a psychophysical olfactory evaluation, we observed anosmia in 52% (N=24), hyposmia in 24% (N=11) and normosmia in 24% (N=11) of patients. The viral load significantly decreased throughout the 14-days following the onset of the olfactory disorder. Conclusions: Our results support that a high proportion of ISOA patients are Covid+. Our study supports the need to add anosmia to the list of symptoms used in screening tools for possible COVID-19 infection.

More than smell - COVID-19 is associated with severe impairment of smell, taste, and chemesthesis

“…Our study confirms and substantially extends previous reports showing that smell loss and taste loss are associated with COVID-19. Similar to other recent studies (Bagheri et al, 2020;Chen et al, 2020;Gane et al, 2020;Giacomelli et al, 2020;Haldrup et al, 2020;Hopkins et al, 2020;Lechien et al, 2020aLechien et al, , 2020bMao et al, 2020;Menni et al, 2020;Moein et al, 2020;Yan et al, 2020aYan et al, , 2020b, we find that the majority of our participants with COVID-19 reports a severe reduction in the ability to smell as compared to before the onset of that disease. Notably, this smell loss was not associated with self-reported nasal obstruction, consistent with anecdotal reports.…”

“…When psychophysical odor identification tests are used, this prevalence ranges from 76% in Europe using the Sniffin' Sticks (Lechien et al, 2020b) to 98% in Iran using the UPSIT (Moein et al, 2020), though the severity of COVID-19 in these study cohorts may not be representative of the larger population. These anecdotes, pre-prints, letters, and peer-reviewed reports (for a review see, Pellegrino et al, in press), describe chemosensory disturbances in COVID-19 with characteristics that are similar to those seen in common URIs, such as isolated sudden onset of anosmia (Gane et al, 2020), occurrence of anosmia in mild or asymptomatic cases of COVID-19 , and loss of taste (Lechien et al, 2020a;Yan et al, 2020a are rare, with the exception of two recent studies: Iravani et al (2020), assessed odor intensity in a group of Swedish respondents, while Moein et al (2020) tested a small sample of hospitalized Iranian patients with the University of Pennsylvania Smell Identification Test. We use three separate sensory modalities -smell, taste and chemesthesis -to sense our chemical environment in daily life.…”

Anosmia as a presenting symptom of SARS-CoV-2 infection in healthcare workers – A systematic review of the literature, case series, and recommendations for clinical assessment and management

“…In the studies that have reported it in COVID-19 tested patients, albeit from surveys, complete resolution was seen in 13% and partial resolution in 14%, with a mean time to improvement of 7.2 days (16) . This is lower than the recovery rates reported by Lechien and colleagues (15) who suggest a short term recovery rate of 44% in 59 patients who had clinically recovered from COVID-19, and also lower than the 73% that reported by Levinson and colleagues (20) , although only 15 patients make up this cohort. Recovery seems to take place within a few weeks but this may be due to short follow up and recovery may happen in others over a longer timeframe.…”

“…Summary findings of the included studies are in Supplemental Table 1 for Anosmia is presenting as the primary symptom or as an early symptom in patients who have tested COVID+. In a European study, 11.8% of patients reported anosmia onset before other otorhinolaryngological symptoms (15) . In the American Academy survey, 26.6% reported it as an isolated initial symptom (16) and…”

Ethyl alcohol threshold test: a fast, reliable and affordable olfactory Assessment tool for COVID-19 patients

“…Nevertheless, they tend to be accompanied by rhinorrhea and nasal obstruction, which does not seem to be common in our COVID-19 sample. Similar results were found in a recent study where patients reporting sudden olfactory loss were tested for SARS-CoV-2 infection [21].…”