CT与核酸检测对新型冠状病毒肺炎诊断及病程演变的对比分析

目的 对比评估CT与核酸检测对新型冠状病毒肺炎（COVID-19）的诊断效能和病程演变特征。 方法 回顾性分析2020年1月20日至3月5日郑州大学第一附属医院收治的164例确诊和疑似COVID-19患者的临床资料、CT和核酸检测结果，其中，确诊COVID-19患者76例男性40例、女性36例，年龄25~83岁]、疑似COVID-19患者88例男性47例、女性41例，年龄21~75岁]。将所有受检者按年龄分为<60岁组（122例）和≥60岁组（42例）。以咽拭子取样核酸检测结果为“金标准”，评估CT对COVID-19的诊断效能。不同年龄组间各诊断效能的比较采用独立样本卡方检验。分析确诊患者自就诊以来的多次CT图像和核酸检测结果，对比COVID-19患者病程演变过程中的临床表现、CT和核酸检测结果的转变规律。 结果 164例患者中，核酸检测最终确诊阳性76例，阳性率为46.3%；CT诊断阳性143例，阳性率为87.2%。CT诊断的灵敏度、特异度、阳性预测值、阴性预测值和准确率分别为96.1%（73/76）、20.5%（18/88）、51.0%（73/143）、85.7%（18/21）、55.5%（91/164）。CT的各诊断效能在<60岁和≥60岁患者之间的差异均无统计学意义（χ2=0.051~0.414，均P>0.05）。88例疑似COVID-19患者中，CT诊断阳性率为79.5%（70/88）。76例确诊患者初诊时，8例（10.5%）为无症状亚临床期，7例（9.2%）CT无阳性表现，11例（14.5%）核酸检测结果为阴性其中9例（81.8%）CT诊断有阳性表现，CT肺炎进展期核酸检测结果转为阳性]。病程演变过程中，CT能清晰显示肺炎的进展和缓解程度，4~8 d后复查，28例CT表现为缓解期的患者中有14例（50.0%）核酸检测结果转阴；9~12 d后复查，46例CT表现为缓解期的患者中有31例（67.4%）核酸检测结果转阴。 结论 CT在早期COVID-19的筛查和诊断中较核酸检测更灵敏，且能更早地评估COVID-19的病程演变，可作为COVID-19临床诊疗过程中的重要辅助手段。

Assessment of CT findings and nucleic acid testing in the diagnosis and the disease course of COVID-19: a comparative study

Objective To evaluate and compare the diagnostic values of CT findings and nucleic acid testing in the corona virus disease 2019 (COVID-19) and investigate their features in the disease course. Methods The retrospective analysis was performed on the data of patients who received chest CT and nucleic acid testing from January 20, 2020 to March 5, 2020 in the First Affiliated Hospital of Zhengzhou University. This study involved 164 patients, including 76 confirmed (40 males and 36 females, aged 25?83 years old) and 88 suspected (47 males and 41 females, aged 21?75 years old) cases. The patients were divided into <60 years old group (122 cases) and ≥60 years old group (42 cases). The performance of CT in diagnosing COVID-19 was assessed using nucleic acid testing results as the gold standard. For confirmed patients with multiple CT images and nucleic acid tests, the CT findings and nucleic acid testing results were analyzed comparatively from the beginning of the disease to the progress and turnover of the disease. Results Of 164 patients, 46.3% (76/164) had positive nucleic acid testing results, and 87.2% (143/164) had positive CT findings. Considering the nucleic acid testing results as standard, the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of CT in diagnosing COVID-19 were 96.1% (73/76), 20.5% (18/88), 51.0% (73/143), 85.7% (18/21), and 55.5% (91/164), respectively. There was no significant difference in CT diagnostic efficiency between <60 years old group and ≥60 years old group (χ2=0.051?0.414, all P>0.05). In patients with negative nucleic acid testing results, 79.5% (70/88) had positive CT findings. In patients with positive nucleic acid testing results, 10.5% (8/76) had no symptom, 9.2% (7/76) had negative CT findings, and 14.5% (11/76) had negative nucleic acid testing results when first examined. Among the 11 patients with initially negative nucleic acid testing results, 81.8% (9/11) had positive CT findings, and the nucleic acid testing results changed from negative to positive during the follow-up period. In the course of disease development, the CT could present progress and improvement. The nucleic acid testing results of 50.0% (14/28) of cases with CT finding improvement changed from positive to negative in the follow-up at 4 to 8 days, and the nucleic acid testing results of 67.4% (31/46) cases changed from positive to negative in the follow-up at 9 to 12 days. Conclusion CT had higher sensitivity for the diagnosis of COVID-19 compared with the initial nucleic acid testing and could show condition improvement earlier than the nucleic acid testing results, it is an important supporting means in clinical practice .