Anosmia and COVID-19

ABSTRACT

Introduction: Anosmia has been described as one of the characteristic symptoms of COVID-19 disease. It is even considered as a key marker for COVID-19 diagnosis. The aim of the study is to evaluate anosmia as prognostic factor in moderate and severe cases of COVID-19 patients. Method(s) Our study is a multicenter prospective study;300 patients were recruited and confirmed COVID-19 infection and admitted into 3 tertiary referral quarantine hospitals to receive medical treatment in Minia, Egypt. The study was conducted between April and October 2021. The selected random sample met the following inclusion criteria adults older than 18 years, rhinopharyngeal swab positive for SARS-CoV-2 infection, and moderate and severe cases of COVID-19. The patients were subjected to the following protocol full clinical history, general medical examination, otorhinolaryngological evaluation, mandatory swab for COVID-19, and recording of laboratory data. Patients underwent olfactory assessment and follow-up for 3 months. Olfactory assessment was done subjectively by odor recognition thresholds using L-butanol;after evaluation, the patients were divided into anosmic and nonanosmic groups. Collected data were compared and statistically analyzed. Result(s) Olfactory impairment was seen in 35% of moderate cases and 13% in severe cases. Our study revealed that patients with anosmia were younger and mostly female. Hospitalized patients with anosmia had a better prognosis. Our results showed no significant differences between the 2 groups regarding temperature, heart rate, and respiratory rate. Of patients with anosmia, 70% were associated with dysgeusia, and 50% recovered within 13 days while 85% recovered within 28 days. There was significant relationship (parallel relationship) between progress of anosmia and level of D-dimer, C-reactive protein, and serum ferritin. This indicateds that the prognosis of anosmia is highly related to the inflammatory process of COVID-19 pathophysiology. Conclusion(s) Anosmic patients with COVID-19 have more favorable prognosis and recovery than nonanosmic patients do, and anosmia improves with treatment of the disease.