The diagnostic value of detecting sudden smell loss among asymptomatic COVID-19 patients in early stage: The possible early sign of COVID-19

Abstract

The newly emerged coronavirus disease 19 , is threatening the world. Olfactory or gustatory dysfunction is reported as one of the symptoms worldwide. As reported so far, different clinical features have been reported according to outbreak sites and gender; most of the patients, who complained of anosmia or hyposmia, were Europeans. We had a fast review for novel articles about COVID-19 infection and olfactory function.Observations: Rapid reviews for COVID-19 or other viral infection and olfactory and/or gustatory dysfunctions were done in this review. Up to date, a lot of reports have shown that olfactory dysfunction is related to viral infections but no exact mechanism, clinical course, and definite treatment have been discovered, which is also same in COVID-19. In general, intranasal steroid (INS) and oral steroid for short time help improve the recovery of the olfactory function in case of olfactory dysfunction after virus infection. Considering severe respiratory complications and immunocompromised state of COVID-19, the use of steroid should be limited and cautious because we do not have enough data to support the usage of steroid to treat olfactory dysfunction in the clinical course of COVID-19. Conclusions and relevance:In the days of pandemic COVID-19, we should keep in mind that olfactory dysfunctions, even without other upper respiratory infection or otolaryngologic symptoms, might be the early signs of COVID-19.

Neuromuscular presentations in patients with COVID-19

“…Another review by Kang et al (21 studies) had similar observations [70]. They found that the use of intranasal or oral steroids enhanced the recovery of COVID-19related olfactory/gustatory dysfunction [70]. We found 11 studies that specifically evaluated gustatory and olfactory functions in patients with COVID-19 infection [71][72][73][74][75][76][77][78][79][80][81].…”

“…They concluded that SARS-CoV-2 may infect neural and oral tissue and thereby present with olfactory and gustatory symptoms. Another review by Kang et al (21 studies) had similar observations [70]. They found that the use of intranasal or oral steroids enhanced the recovery of COVID-19related olfactory/gustatory dysfunction [70].…”

“…We identified 2 meta-analyses of 24 and 21 studies/case reports respectively that described patients with olfactory/ gustatory dysfunction [69,70]. In addition, we describe 11 studies that evaluated olfactory/gustatory dysfunction in COVID-19 patients (Table 6) [71][72][73][74][75][76][77][78][79][80][81].…”

Onset and duration of symptoms of loss of smell/taste in patients with COVID-19: A systematic review

“…In Brazil, a study carried out with 253 recovered patients, showed that 212 had experienced sudden-onset anosmia and 196 had developed loss of smell accompanied by nonspecific inflammatory symptoms [ 6 ]. Sudden changes in smell thus came to be seen as initial signs of COVID-19 [ 7 ] and, anosmia, in the absence of other symptoms, such as rhinorrhea or nasal congestion, may be an indicator of SARS-CoV-2 infection [ [8] , [9] , [10] , [11] , [12] ].…”

Quantitative assessment of olfactory dysfunction accurately detects asymptomatic COVID-19 carriers

“…Identifying and isolating asymptomatic patients is critical for preventing the rapid spread of COVID-19. Considering the reports of smell dysfunctions and their predictability [ 21 , 22 ], we hypothesized that a multitude of olfactory dysfunctions could occur in asymptomatic carriers [ 9 , [23] , [24] , [25] , [26] ]. Assessing minor dysfunctions may not be possible with traditionally used methods due to the lack of precision in delivering stimuli to individuals [ 27 , 28 ].…”