ABSTRACT
BackgroundThe pandemic of coronavirus disease 2019 (COVID-19) has become the first concern in international affairs as the novel coronavirus (SARS-CoV-2) is spreading all over the world at a terrific speed. The accuracy of early diagnosis is critical in the control of the spread of the virus. Although the real-time RT-PCR detection of the virus nucleic acid is the current golden diagnostic standard, it has high false negative rate when only apply single test. ObjectiveSummarize the baseline characteristics and laboratory examination results of hospitalized COVID-19 patients. Analyze the factors that could interfere with the early diagnosis quantitatively to support the timely confirmation of the disease. MethodsAll suspected patients with COVID-19 were included in our study until Feb 9th, 2020. The last day of follow-up was Mar 20th, 2020. Throat swab real-time RT-PCR test was used to confirm SARS-CoV-2 infection. The difference between the epidemiological profile and first laboratory examination results of COVID-19 patients and non-COVID-19 patients were compared and analyzed by multiple logistic regression. Receiver operating characteristic (ROC) curve and area under curve (AUC) were used to assess the potential diagnostic value in factors, which had statistical differences in regression analysis. ResultsIn total, 315 hospitalized patients were included. Among them, 108 were confirmed as COVID-19 patients and 207 were non-COVID-19 patients. Two groups of patients have significance in comparing age, contact history, leukocyte count, lymphocyte count, C-reactive protein, erythrocyte sedimentation rate (p<0.10). Multiple logistic regression analysis showed age, contact history and decreasing lymphocyte count could be used as individual factor that has diagnostic value (p<0.05). The AUC of first RT-PCR test was 0.84 (95% CI 0.73-0.89), AUC of cumulative two times of RT-PCR tests was 0.92 (95% CI 0.88-0.96) and 0.96 (95% CI 0.93-0.99) for cumulative three times of RT-PCR tests. Ninety-six patients showed typical pneumonia radiological features in first CT scan, AUC was 0.74 (95% CI 0.60-0.73). The AUC of patients age, contact history with confirmed people and the decreased lymphocytes were 0.66 (95% CI 0.60-0.73), 0.67 (95% CI 0.61-0.73), 0.62 (95% CI 0.56-0.69), respectively. Taking chest CT scan diagnosis together with patients age and decreasing lymphocytes, AUC would be 0.86 (95% CI 0.82-0.90). The age threshold to predict COVID-19 was 41.5 years, with a diagnostic sensitivity of 0.70 (95% CI 0.61-0.79) and a specificity of 0.59 (95% CI 0.52-0.66). Positive and negative likelihood ratios were 1.71 and 0.50, respectively. Threshold of lymphocyte count to diagnose COVID-19 was 1.53x109/L, with a diagnostic sensitivity of 0.82 (95% CI 0.73-0.88) and a specificity of 0.50 (95% CI 0.43-0.57). Positive and negative likelihood ratios were 1.64 and 0.37, respectively. ConclusionSingle RT-PCR test has relatively high false negative rate. When first RT-PCR test show negative result in suspected patients, the chest CT scan, contact history, age and lymphocyte count should be used combinedly to assess the possibility of SARS-CoV-2 infection.
ABSTRACT
ObjectiveTo describe the epidemiological and clinical characteristics of the Coronavirus Disease 2019 (COVID-19) hospitalized patients and to offer suggestions to the urgent needs of COVID-19 prevention, diagnosis and treatment. MethodsWe included 102 confirmed COVID-19 cases hospitalized in Xiangyang No.1 peoples hospital, Hubei, China until Feb 9th, 2020. Demographic data, laboratory findings and chest computed tomographic (CT) images were obtained and analyzed. FindingsAll cases were confirmed by real-time RT-PCR, including 52 males and 50 females with a mean age of 50.38 years (SD 16.86). Incubation time ranged from one to twenty days with a mean period of 8.09 days (SD 4.99). Fever (86[84.3%] of 102 patients), cough (58[57%]), fatigue (28[27%]), shortness of breath (24[23%]), diarrhea (15[15%]), expectoration (13[12%]), inappetence (11[10%]) were common clinical manifestations. We observed a decreased blood leukocyte count and lymphopenia in 21 (20.6%) and 56 (54.9%) patients, respectively. There were 66 (68%) of 97 patients with elevated C-reactive protein levels and 49 (57.6%) of 85 with increased erythrocytes sedimentation rate. Higher levels of procalcitonin and ferritin were observed in 19 (25.3%) of 75 and 12 (92.3%) of 13 patients, respectively. Eight patients were admitted to intensive care unit (ICU), six developed respiratory failure, three had multiple organ failure and three died. The cumulative positivity rate over three rounds of real-time RT-PCR was 96%. One-hundred patients were found with typical radiological abnormalities in two rounds of chest CT scans, indicating a 98% consistency with real-time RT-PCR results. InterpretationMost COVID-19 patients in Xiangyang were secondary cases without sex difference, and the rate of severe case and death was low. Middle-to-old-age individuals were more susceptible to the virus infection and the subsequent development of severe/fatal consequences. The average incubation period was longer among our patients. We recommend prolonging the quarantine period to three weeks. Three times real-time RT-PCR plus two times CT scans is a practical clinical diagnosis strategy at present and should be used to increase the accuracy of diagnosis, thereby controlling the source of infection more effectively.
