新型冠状病毒肺炎患者胸腺多层螺旋CT表现

CT characteristics of the thymus in coronavirus patients

目的分析新型冠状病毒肺炎(COVID-19)患者胸腺CT图像,探讨其胸腺的CT表现特点及动态变化。方法回顾性分析2020年1月至3月重庆三峡中心医院收治的241例确诊为COVID-19患者的CT资料,对比2019年11月至12月242例胸部CT检查正常者的CT资料,比较胸腺CT分类、左右径、前后径及平均CT值在COVID-19患者和对照组、COVID-19患者不同临床类型、COVID-19患者治疗前和治疗后是否存在差异。结果①胸腺CT分类:胸腺分类在COVID-19患者与对照组差异有统计学意义(χ^2=19.066,P=0.000),COVID-19患者胸腺脂肪型64.7%(156/241)、脂肪为主17.8%(43/241)、脂肪和软组织各半11.2%(27/241)、软组织为主6.2%(15/241),对照组胸腺脂肪型48.3%(117/242)、脂肪为主25.6%(62/242)、脂肪和软组织各半10.3%(25/242)、软组织为主15.7%(38/242)。胸腺脂肪型是40~59岁人群感染COVID-19的危险因素(OR=3.071,P=0.000)。胸腺脂肪化率在COVID-19不同临床类型患者排序为重型及危重型>普通型>轻型。②大小:胸腺大小在COVID-19患者与对照组比较差异无统计学意义(P>0.05);在COVID-19患者轻型、普通型、重型及危重型三组间差异无统计学意义(P>0.05);在治疗前和治疗后差异无统计学意义(P>0.05),并与治疗时间无相关性(r=0.047、r=0.071)。③密度:胸腺CT值在COVID-19患者与对照组间差异无统计学意义(P>0.05);在COVID-19患者轻型、普通型、重型及危重型三组间差异无统计学意义(P>0.05)。有1例治疗后胸腺密度增高17HU,但78例胸腺CT值在治疗前和治疗后差异无统计学意义(P>0.05),并与治疗时间无相关性(r=0.013)。结论COVID-19患者胸腺脂肪化率高,且临床分型越重胸腺脂肪化率越高;胸腺脂肪化是40~59岁人群新型冠状病毒(2019-nCoV)感染的危险因素。

Objective To investigate the characteristics of thymus in patients with COVID-19,and to analyze the CT features and dynamic changes of thymus.Methods Data of 241 patients diagnosed with COVID-19 admitted to Chongqing Three Gorges Central Hospital from Jan.to Mar.2020 were retrospectively analyzed,and 242 consecutive subjects were selected as the control group from Nov.to Dec.2019.The thymus classification,size,and average CT values between COVID-19 patients and the control group were compared,as well as those among different clinical types for COVID-19 patients,before and after treatment,were analyzed.Results①The attenuation of the thymus:64.7%(156/241)complete fatty replacement thymus,17.8%(43/241)predominantly fatty thymus,11.2%(27/241)approximately one-half fatty and one-half soft-tissue-attenuation thymus,and 6.2%(15/241)predominantly soft-tissue thymus in COVID-19 patients were found.48.3%(117/242)complete fatty replacement thymus,25.6%(62/242)predominantly fatty thymus,10.3%(25/242)approximately one-half fatty and one-half soft-tissue-attenuation thymus,and 15.7%(38/242)predominantly soft-tissue thymus were found in the control group.Complete fatty replacement thymus was an independent factor affecting COVID-19 in 40 to 59 years old patients(OR=3.071,P=0.000).The rate of complete fatty replacement thymus:severe or critical type>common type>mild type.②Size:There was no statistical difference of the thymus size between COVID-19 patients and the control group(P>0.05),no statistical difference among the mild type,common type and severe or critical type(P>0.05),no statistical difference between before and after treatment(P>0.05),and there was no correlation with treatment duration(r=0.047,r=0.071).③Density:There was no statistical difference of the CT value of thymus between COVID-19 patients and the control group(P>0.05),no statistical difference among the mild,common and severe type(P>0.05).One patient had a 17 HU increase in thymus density after treatment,but there was no statistical difference in 78 patients in thymus CT values between before and after treatment(P>0.05),and there was no correlation with treatment duration(r=0.013).Conclusions COVID-19 patients have a high rate of complete fatty replacement thymus.And the heavier the clinical classification,the higher the rate of complete fatty replacement thymus.Complete fatty replacement thymus is a risk factor for COVID-19 patients in 40 to 59 years old.