Taste and smell as chemosensory dysfunctions in COVID-19 infection.

PURPOSE: To review the literature on the presence of two clinical manifestations in patients presenting COVID-19 (SARS-CoV-2) infection: loss of taste (ageusia) and loss of smell (anosmia). METHODS: PubMed and EMBASE were searched and studies were selected starting from November, 2019 until April 2020; also, the references of the selected articles were evaluated for methodological quality. RESULTS: Of the 19 studies analyzed, five were included to evaluate the presence of ageusia and/or anosmia as symptoms in patients who were tested and resulted positive for the SARS-CoV-2 virus. In a total of 10,818 patients, 8,823 presented ageusia (81.6%; range 5.6%-88%) and 8,088 presented anosmia (74.8%; range 5.1-85.6%). Only one study recorded both symptoms with a percentage of 18.6%. CLINICAL SIGNIFICANCE: This systematic review demonstrated significant presence of ageusia and anosmia in the patients with COVID-19 infection. These symptoms may be considered as the first manifestation of the infection.