76例重症甲型H1N1流感的影像学表现及动态观察

目的：探讨重症甲型H1N1流感的胸部影像学表现。方法：回顾性分析76例重症甲型H1N1流感的影像学资料,将所有病例根据临床特点和病程分为三组：第1组（n=50）：门诊病例或是住院时间很短的病例;第2组（n=14）：临床上有急性呼吸衰竭但未用机械通气的病例;第3组（n=12）：急性呼吸衰竭同时需要机械通气的病例。观察所有患者平片、CT表现,并对病变的大小、形态、数目和分布加以分析。结果：重症甲型H1N1流感的主要影像学表现为双侧或单侧的磨玻璃样改变、实变或混合型病变,第1组以磨玻璃样改变为主,病变一般多发,可侵及所有肺叶,但主要发病部位为双肺下叶,多呈周围性分布;第2组以实变为主,可合并磨玻璃样改变或局灶性实变,恢复期可有少数病例呈纤维性修复;第3组以实变为主,可合并间质性改变,单纯磨玻璃样改变少见;少数病例可合并胸腔积液、心包积液和肺不张;第3组部分病例可伴有继发性气胸、纵膈气肿、皮下气肿以及霉菌感染,继发肺动脉高压、右心衰竭、肝脾淤血。结论：在不同的临床病程中患者有不同的影像学表现。轻症病例影像学表现比较轻微,恢复也比较彻底,一些重症病例可呈纤维性修复,而危重病例,尤其是需要机械性通气的病例其并发症尤其是气胸的发生概率较高,且病情变化比较反复,在病变进展期及时复查X线胸片以了解影像的变化,对于正确地评估病情、采取积极恰当的治疗措施将起到重要的指导作用。

Manifestations and dynamic observation of imaging findings in 76 patients with severe influenza A (H1N1) viral infection

Objective：To study the imaging findings of severe influenza A （H1N1） infection. Methods：The imaging materials of 76 patients with severe influenza A （H1N1） were retrospectively analyzed.All of the patients were divided into three groups based on the clinical course.Group 1 （n=50） included the patients either treated as out-patients or with short hospitalization.Group 2 （n=14） included patients with acute respiratory distress syndrome （ARDS） but without advanced mechanical ventilation.Group 3 （n=12） included patients with acute respiratory failure and advanced mechanical ventilation was required.The chest radiographic and CT findings including the size,morphology,number and distribution of the pulmonary lesions were analyzed.Results：The main imaging findings of severe influenza A （H1N1） infection were unilateral/bilateral pulmonary ground-glass opacities （GGO）,consolidation or mixed pattern.In Group 1,GGO was the major features,generally showed multiple lesions,all pulmonary lobes but mainly bilateral lower lobes could be involved,mostly located at the periphery of lung.Consolidation was the main finding in Group 2,might be associated with GGO or focal consolidations.Fibrosis was assessed in the recovering stage of a few patients.The most common pattern of Group 3 was pulmonary consolidation,might be associated with interstitial changes.Simple GGO was uncommon.Pleural/pericardial effusion and pulmonary atelectasis might be revealed in some of the patients.Secondary pneumothorax,pneumomediastinum,subcutaneous emphysema and fungal infection,secondary pulmonary hypertension,right heart failure,liver and spleen congestion could be complicated in Group 3 patients.Conclusion：Different imaging manifestations could be revealed in different clinical stages of influenza A （H1N1） patients.The imaging manifestations were in a minor extent in mild type of infection,complete recovery could be obtained.Fibrosis could be seen in some serious patients.For critical, especially those required mechanical ventilation,repeatedly relapse of the disease could be assessed.In the advanced stage,following-up radiography in time is helpful to evaluate the course of illness,and play an important role in the guidance of appropriate treatment.