摘要目的 探讨显微镜下多血管炎(MPA)合并肺感染的胸部CT表现及实验室检查特点.方法 回顾性分析42例临床确诊为MPA患者的临床资料和胸部CT表现.根据痰培养结果,将患者分为MPA合并肺感染组(16例)及单纯MPA组(26例),对比分析两组间胸部CT表现和实验室检查的差异.统计学方法采用χ2检验、Fisher精确检验、独立样本t检验和Mann-Whitney U检验.结果与单纯MPA组相比,MPA合并肺感染组的胸部CT更多表现为斑片影(两组分别为15、14例,χ2=5.631,P=0.018)和实变影(两组分别为7、2例,χ2=5.657,P=0.017),且MPA合并肺感染组的斑片影(6例)较单纯MPA组(12例)更少表现为外周带分布(P=0.021),两组间差异均有统计学意义;而磨玻璃影、胸腔积液、淋巴结增大及间质纤维化等表现在两组间差异均无统计学意义(P值均>0.05);此外, MPA合并肺感染组中性粒细胞比例(0.84±0.12)高于单纯MPA组(0.74±0.11),差异具有统计学意义(t=2.845,P=0.007),而白细胞、中性粒细胞、红细胞沉降率、抗髓过氧化物酶抗体值及C反应蛋白等数据在两组间差异均无统计学意义(P值均>0.05).结论 与单纯MPA患者相比,MPA合并肺感染患者更多表现为斑片影和实变影,中性粒细胞比例更高.临床中具有上述表现的MPA患者,应警惕肺感染可能,积极进行痰培养并进行针对性抗感染治疗.

abstractsObjective To investigate the imaging features of chest CT and characteristics of laboratory tests in microscopic polyangitis (MPA) with pulmonary infection. Methods Based on the results of sputum culture, 42 patients with MPA were divided into two groups, MPA with pulmonary infection (16 cases)and MPA without pulmonary infection (26 cases). The results of chest CT images and laboratory tests were compared between the 2 groups by χ2 test (or Fisher exact test) and student t test (or Mann-Whitney U test), respectively. Results Compared with patients without pulmonary infection, patients with pulmonary infection showed patchy opacities(15/16 cases versus 14/26 cases,χ2=5.631,P=0.018)and consolidations(7/16 cases versus 2/26 cases,χ2=5.657,P=0.017)more frequently. Patchy opacities showed peripheral distribution less frequently in the MPA with pulmonary infection group than in the MPA without pulmonary infection group (6/15cases versus 12/14 cases,P=0.021). Patients with pulmonary infection showed the same frequent as the patients without pulmonary infection in the following CT findings including ground glass opacities, pleural effusions, mediastinal adenopathy and pulmonary fibrosis (P>0.05). The MPA with pulmonary infection group had higher neutrophil ratio than the MPA without pulmonary infection group (0.84 ± 0.12 versus 0.74 ± 0.11,t= 2.845,P= 0.007). Conclusions The MPA patients with pulmonary infection show patchy opacities and consolidations more frequently, and have higher neutrophil ratio than the MPA without pulmonary infection. The characteristics can be helpful in the diagnosis of pulmonary infection in the MPA patients and guild the treatment.