Chest CT diagnostic potential as a tool for early detection of suspected COVID-19 cases in pandemic peaks

Abstract

Introduction: The emergence of severe acute respiratory syndrome coronavirus disease (COVID­19) in China at the end of 2019 caused a massive global outbreak that has become a major public health issue.Aim: Our aim was to investigate the diagnostic potential of chest CT in screening patients suspected of having COVID­19 in high­prevalence settings.Materials and methods: This is a real­life, prospective, observational study involving 260 patients. All patients received chest CT scan at the emergency department (ED) of Kaspela University Hospital, Plovdiv, Bulgaria and RT­PCR testing for suspected COVID­19 from March 27 to December 31, 2020. COVID­19 likelihood was assessed by assigning each CT scan to a particular category of the COVID­19 Reporting and Data System (CO­RADS). IBM SPSS v. 26 was used to process the data.Results: The male­to­female distribution ratio was 1.4:1 – 150 (57.7%) males vs. 110 (42.3%) females (p=0.014). The median age was 55 yrs (range 46–65 yrs). Discharged patients were 247 (95.0%), the rest died in the COVID­19 intensive care unit. Males were 4.13 times more likely to be diagnosed with CO­RADS≥3 score than females. Increasing age was associated with an increased likelihood of being classified with higher CO­RADS scores. The ROC curves analysis demonstrated that CO­RADS ≥3 was the optimal cutoff for discrimi­nating between a positive and negative PCR (Youden’s index J=0.67), with an AUC of 0.825 (95% CI 0.72­0.93), sensitivity of 91.9% (95% CI 87.7%­95.1%), specificity of 75.0% (95% CI 53.3%­90.2%) and accuracy of 76.4% (95% CI 70.7%­81.4%).Conclusions: The results of this study reveal that a CT examination can provide a quick and accurate diagnosis of patients with sus­pected COVID­19 infection, whereas the PCR test is time­consuming, and the delay in receiving results can be substantial when the incidence curve begins to grow rapidly.

Keywords

• CO­RADS
• RT­PCR
• SARS­CoV­2
• sensitivity
• specific