Smell loss associated with SARS-CoV-2 is not clinically different from other viruses: a multicenter cohort study.

BACKGROUND: Although the COVID-19 pandemic has increased the prevalence of cases with olfactory loss, other respiratory viruses can also cause this condition. We aimed to compare the prevalence of acute SARS-CoV-2 infection and other respiratory viruses in patients with sudden smell loss, and to assess the impact of SARS-CoV-2 viral load and co-infection on olfactory symptoms. METHODS: Patients with sudden smell loss were recruited in a multicenter prospective cohort study in 15 hospitals in Brazil. Clinical questionnaire, Connecticut Chemosensory Clinical Research Center (CCCRC) olfactory test and nasopharyngeal swab to perform a PCR-based respiratory viral panel were collected at first visit (day 0) and 30 and 60 days after recruitment. RESULTS: 188 of 213 patients presented positive test result for SARS-CoV-2, among which 65 were co-infected with other respiratory viruses (e.g., rhinovirus, enterovirus, and parainfluenza). 25 had negative test results for SARS-CoV-2. Patients in both SARSCoV-2 and non-SARS-CoV-2 groups had objective anosmia (less than 2 points according to the psychophysical olfactory CCCRC) at day 0, with no significant difference between them. Both groups had significant smell scores improvement after 30 and 60 days, with no difference between them. Co-infection with other respiratory viruses, and SARS-CoV-2 viral load did not impact olfactory scores. CONCLUSION: Patients with sudden smell loss associated with SARS-CoV-2 and other respiratory viruses had similar presentation, with most participants initiating with anosmia, and total or near total recovery after 60 days. SARS-CoV-2 viral load and co-infections with other respiratory viruses were not associated with poorer olfactory outcomes.

Chest CT imaging features of COVID-19 pneumonia: First radiological insights from Porto, Portugal.

INTRODUCTION: The outbreak of a highly infectious respiratory disease - COVID-19 - has spread globally and a novel type of coronavirus (SARS-CoV-2) was identified as its cause. Chest CT findings have been described as an aid for COVID-19 diagnosis and management. We aimed to describe the CT imaging characteristics in a group of COVID-19 patients while we also intended to assess if any of these radiological features were associated with short-term prognosis. MATERIALS AND METHODS: CT examinations from 164 consecutive patients with at least one positive RT-PCR nucleic acid assay for SARS-CoV-2 were retrospectively analyzed. Numerous CT imaging features were recorded independently by two radiologists. Patients were grouped according to their status 14 days after the initial CT scan in either discharged/hospitalized in a non-ICU ward (favorable prognosis group) versus deceased/admitted to an intensive care unit (unfavorable prognosis group). RESULTS: Ground-glass opacities (89.0 %) and consolidations (73.2 %) with multilobar involvement were the predominant imaging findings, while a nodular pattern (3.7 %) and cavitation (1.2 %) were uncommon. Mean age was higher in the mortality/ICU group. Ground-glass opacities and consolidations were dominant in both groups, but distribution pattern of abnormalities was different, being more often diffuse in the mortality/ICU group. Linear opacities and opacities that were rounded in shape were more frequently observed in the favorable prognosis group. CT severity index was significantly higher in the mortality/ICU group. For assessing unfavorable prognosis, the best cut-off for CT severity index was 24 (sensitivity 78 %; specificity 59 %). Interobserver agreement for all CT findings was excellent. CONCLUSION: COVID-19 pneumonia in Porto, Portugal, manifests as multilobar ground-glass opacities and consolidations. Older age, diffuse distribution and increasing CT severity index are associated with worse short-term prognosis while linear opacities resembling organizing pneumonia and rounded opacities herald a more favorable prognosis.