Performance Of Chest Computed Tomography And Real-Time Reverse Transcription Polymerase Chain Reaction In COVID-19 Diagnosis

Background and Objective2019-Coronavirus Disease(COVID-19)spread globally.Real-time Reverse Transcription Polymerase Chain Reaction(RT-PCR)nucleic acid detection is the gold standard for clinical diagnosis of COVID-19,however,it has low sensitivity.Chest CT plays an important role in the diagnosis and treatment of COVID-19,but the diagnostic efficacy of COVID-19 is not yet clear.This study intends to analyze the sensitivity and specificity of the first chest CT examination for the diagnosis of COVID-19,and compare it with the first RT-PCR nucleic acid test,which is to provide a reference for epidemic prevention and control.Materials and MethodsThe clinical data of 126 patients with COVID-19 from Ningbo multiple hospitals between January 23,2020 and February 24,2020 were collected retrospectively,including the patient’s age,gender,contact history,date of first symptom onset,and first visit time,clinical symptoms,time and result of the first chest CT examination,time and result of the first RT-PCR nucleic acid test.We selected randomly 126 suspected cases that finally ruled out COVID-19 infection as a control in the same period from fever clinics.First,the sensitivity and specificity of the first chest CT examination were analyzed in different groups of the general population,male population,and female population,which were compared with the first RT-PCR nucleic acid test,respectively.Second,the factors affecting the first chest CT examination and the first RT-PCR nucleic acid sensitivity in COVID-19 patients were analyzed.Results1.The sensitivity and specificity of the first chest CT examination were 71.4%(95%CI,62.7%-79.1%),77.8%(95%CI,69.5%-84.7%),and the area under the ROC curve was 0.75(95%CI,0.69,0.80).The sensitivity and specificity of the first RT-PCR nucleic acid test were61.0%(95%CI,50.7%-70.6%),100.0%(95%CI,97.1%-100.0%),and the area under the ROC curve was 0.81(95%CI,0.76,0.85).Compared with the first RT-PCR nucleic acid test,the first chest CT test has higher sensitivity and lower specificity.There were no significant difference in the diagnostic efficacy between the first chest CT examination and first RT-PCR nucleic acid test(P > 0.05).2.For the first chest CT examination,the area under the ROC curve was 0.74(95%CI,0.65-0.82)in male patients,and the area under the ROC curve was 0.75(95%CI,068-0.82)in female patients.For the first RT-PCR nucleic acid test,the area under the ROC curve in male patients was0.82(95%CI,0.74-0.89)in male patients,and the area under the ROC curve was 0.80(95%CI,0.74-0.86)in female patients.There were no significant differences between the groups(P > 0.05).3.Compared with patients with positive chest CT group for the first time,patients with negative chest CT group for the first time were younger,and the difference was statistically significant(43.5 vs 53,P <0.05).Compared with positive chest CT group for the first time,patients with fever were fewer in negative chest CT group for the first time,there were no significant differences(58.3% vs 65.6%,P> 0.05).Between negative and positive CT groups for the first time,there were no significant differences in incubation period(P> 0.05),interval time between the first symptom onset and the first visit(P > 0.05),and the interval time between contact with the source of infection and the first visit(P > 0.05).Compared with positive RT-PCR nucleic acid tests group for the first time,patients with fever were fewer in negative RT-PCR nucleic acid tests group for the first time,and the difference was significant(51.3% vs 77.1%,P <0.05).Between negative and positive CT groups for the first time,there were no significant difference in age(50 vs 53,P> 0.05),incubation period(8d vs 5d,P> 0.05),interval time between the first symptom onset and the first visit(P > 0.05),and the interval time between contact with the source of infection and the first visit(P > 0.05).Conclusions1.Compared with the first RT-PCR nucleic acid test,the first chest CT examination has higher sensitivity and lower specificity in the diagnosis of COVID-19.It is suggested that the first chest CT examination is helpful for early identification and isolation of the source of infection.2.In COVID-19 patients,the age is the main factor affecting the sensitivity of the first chest CT examination,it suggests that the sensitivity of the first chest CT examination may be related to the severity of the disease.The fever is the main factor affecting the sensitivity of the first RT-PCR nucleic acid test,it suggests that those with a history of epidemiology but no fever should be treated with caution when the first RT-PCR nucleic acid test is negative.