Diagnostic accuracy of symptoms as a diagnostic tool for SARS-CoV 2 infection: a cross-sectional study in a cohort of 2,173 patients 

Abstract

Background: The SARS-CoV-2 pandemic continues to be a priority health problem; According to the World Health Organization data from October 13, 2020, 37,704,153 confirmed COVID-19 cases have been reported, including 1,079,029 deaths, since the outbreak. The identification of potential symptoms has been reported to be a useful tool for clinical decision-making in emergency departments to avoid overload and improve the quality of care. The aim of this study was to evaluate the performances of symptoms as a diagnostic tool for SARS -CoV-2 infection.Methods: An observational, cross-sectional, prospective and analytical study was carried out, during the period of time from April 14 to July 21, 2020. Data (demographic variables, medical history, respiratory and non-respiratory symptoms) were collected by emergency physicians. The diagnosis of COVID-19 was made using SARS-CoV-2 RT-PCR. The diagnostic accuracy of these characteristics for COVID-19 was evaluated by calculating the positive and negative likelihood ratios. A Mantel-Haenszel and multivariate logistic regression analysis was performed to assess the association of symptoms with COVID-19.Results: A prevalence of 53.72% of SARS-CoV-2 infection was observed. The symptom with the highest sensitivity was cough 71%, and a specificity of 52.68%. The symptomatological scale, constructed from 6 symptoms, obtained a sensitivity of 83.45% and a specificity of 32.86%, taking ≥ 2 symptoms as a cut-off point. The symptoms with the greatest association with SARS-CoV-2 were: anosmia odds ratio (OR) 3.2 (95% CI; 2.52-4.17), fever OR 2.98 (95% CI; 2.47-3.58), dyspnea OR 2.9 (95% CI; 2.39-3.51]) and cough OR 2.73 (95% CI: 2.27-3.28).Conclusion: The combination of symptoms associated with SARS-CoV-2 infection results in a highly predictive model for a rapid and accurate diagnosis of the disease, in the absence of auxiliary diagnostic studies. Evaluating the symptoms in isolation and in combination could be an appropriate strategy to be used in the emergency services to guide behavior in the face of the disease.Trial registration: Institutional registration R-2020-3601-145, Federal Commission for the Protection against Sanitary Risks 17 CI-09-015-034, National Bioethics Commission: 09 CEI-023-2017082.

Dispneia Ansiosa e Dispneia por COVID-19: um Diagnóstico Diferencial

“…Na infecção por SARS-CoV-2, a dispneia ocorre devido à lesão pulmonar. A presença do vírus aumenta a expressão de receptores ECA2 nas células apicais pulmonares, o que promove a adesão, penetração e destruição do tecido pulmonar, além da formação de exsudato inflamatório intersticial, alveolar e edema [6], [12].…”

“…Na ansiedade, a dispneia pode não vir acompanhada de hipoxemia, por estar relacionada a uma hiperpercepção das sensações respiratórias e aumento da tensão muscular respiratória, podendo estar mais associada a sintomas de hipocapnia [5], [11]. Enquanto na COVID-19, a falta de ar pode vir associada à hipoxemia, por ser causada por uma lesão pulmonar [12]. Todavia, a ausência de hipoxemia não exclui a possibilidade de ser infecção por SARS-Cov-2, já que a dispneia pode vir na ausência de hipoxemia nesse grupo, como foi visto nos casos em que esses indivíduos com COVID-19 apresentavam altos níveis de ansiedade [1].…”

“…Febre e tosse fizeram parte dos sintomas mais frequentes em pacientes com COVID-19 nos artigos analisados. A combinação desses dois sintomas, com a adição da dispneia, foi descrita como tríade de sintomas da COVID-19 pelo Centro de Controle e Prevenção de Doenças dos Estados Unidos [3], [12]. Sintomas olfatórios também apresentaram uma incidência considerável de 44,40%.…”

“…Sintomas olfatórios também apresentaram uma incidência considerável de 44,40%. A fisiopatologia da anosmia parece estar relacionada com a via de infecção do vírus para o Sistema Nervoso Central, que uma das rotas é pela placa cribriforme através do epitélio do nervo olfatório [15], [12]. Desse modo, presença de febre, tosse ou anosmia além da dispneia pode auxiliar no diagnóstico da COVID-19.…”

Beware of traumatic anosmia in COVID-19 pandemic

“…Among patients presenting to the ED with influenza-like symptoms, the presence of anosmia was associated with a 14-fold increase in the positivity rate of COVID-19 [ 1 ]. The most common symptoms associated with COVID-19 are fever, dyspnea, cough, and anosmia, of which anosmia is reported to have the highest odds ratio of 3.2 [ 2 ]. Patients with COVID-19 have a higher rate of anosmia, because coronaviruses can damage the olfactory neuroepithelium by apoptosis, followed by a decrease in mature sensory neurons [ 3 ].…”