Screening for 274 suspected cases of novel coronavirus pneumonia

Abstract

Objective To evaluate the diagnostic efficacies of computed tomography (CT), clinical manifestations and 2019 novel coronavirus (2019-nCoV) nucleic acid test results for the screening and diagnosis of novel coronavirus pneumonia. Methods The clinical data of cases suspected with coronavirus disease 2019 (COVID-19) visited fever clinic or stayed in emergency room of the First Affiliated Hospital of Nanchang University from January 23, 2020 to February 9, 2020 were collected. Totally 274 cases who met the inclusion criteria were enrolled. Four screening schemes including chest CT screening, scoring, chest CT and scoring series screening, chest CT and scoring parallel screening were designed. The statistical analysis was performed by using chi-square test. The sensitivities, specificities and the areas under the receiver operator characteristic curve of the four screening schemes were calculated, and the diagnostic efficacies were evaluated. Results Among the 274 cases, 93.80% (257/274) presented with typical clinical symptoms, 47.81% (131/274) had epidemiological history, and the blood routine examination results of 45.26% (124/274) cases met the positive criteria of the scoring , and chest CT results of 43.07% (118/274) cases met the positive criteria of chest CT screening. The 2019-nCoV nucleic acid test positive rate of cases with epidemiological history was 30.53% (40/131), which was higher than that of cases without epidemiological history (9.09% (13/143)) , and that of cases with typical imaging performance on chest CT was 40.68% (48/118), which was higher than cases without typical imaging performance (3.21% (5/156)) . The differences between the above groups were both statistically significant (both P<0.01). The positive rates of viral nucleic acid detection in cases with positive findings of chest CT screening, scoring, series screening, and parallel screening were 40.68% (48/118), 23.74% (47/198), 4.25% (42/94) and 23.87% (53/222), respectively, while those in cases with negative findings of the four screening schemes were 3.20% (5/156), 7.89% (6/76), 6.11% (11/180) and 0 (0/52), respectively. The positive rates of the four screening schemes were all significantly different from that of viral nucleic acid detection (all P<0.01). The chest CT screening method had a sensitivity of 90.57%, a specificity of 68.33%, and an area under the operating characteristic curve of the subject was 0.794, which had higher diagnostic value than those of the other three screening schemes. Conclusions For the screening and diagnosis of COVID-19 cases, epidemiological history, positive viral nucleic acid test with ≥2 typical clinical manifestations have highly diagnostic value. On the basis of the preliminary screening of chest CT examination, flexible analysis of the diagnostic results could improve the diagnostic value of each detection method. Key words: COVID-19; Pneumonia; Chest CT; Real-time polymerase chain reaction; Screening