51例不明原因重症肺炎导致急性肺损伤的临床分析

Acute lung injury resulted from severe pneumonia of unknown origin:report of 51 cases

目的提高对不明原因重症肺炎导致急性肺损伤的认识。方法回顾性分析甲型H1N1流感暴发流行期间同济大学医学院附属上海市肺科医院急诊科收治的51例伴有急性肺损伤的不明原因重症肺炎病例。结果 51例患者临床表现为咳嗽51例,咳痰31例,发热45例,气急51例,肌肉酸痛13例;入院时氧合指数(PaO_2/FiO_2)200～300者22例,<200者29例。影像学表现以双肺渗出性改变为主,有斑片状、毛玻璃状、网状和结节样改变,病灶迅速进展或融合。本组双侧肺病变占94.1%(48/51)。15例死亡,病死率29.4%(15/51),死亡病例均为急性呼吸窘迫综合征(ARDS)病例,占ARDS病例数51.7%(15/29),10例有基础肺病,占死亡病例66.7%。51例患者中,41例使用甲泼尼龙静脉给药治疗,28例患者存活。明确诊断6例,为侵袭性肺曲霉病3例,甲型H1N1流感3例。51例血清支原体、衣原体、军团菌抗体均阴性。痰真菌培养肺曲霉阳性6例中,G试验阳性2例,GM试验均阴性。人类免疫缺陷病毒(HIV)抗体阳性6例。32例进行血清病毒(巨细胞病毒、腺病毒和呼吸道合胞病毒)抗体检测,巨细胞病毒IgG阳性9例。结论重症肺炎导致急性肺损伤的病因学诊断是临床难题,存在基础肺部疾病可能与重症肺炎的预后相关。激素的早期应用对急性肺损伤的预后有一定的积极作用。

Objective To further increase the awareness of the acute lung injury resulted from severe pneumonia of unknown origin. Methods The medical data of 51 cases with acute lung injury following severe pneumonia treated in our emergency department during epidemic of influenza A H1N1 were reviewed retrospectively. Results The clinical symptoms included cough in 51 cases, productive cough （31）, fever （45）, breathlessness （51）, and myalgia （13）. The oxygenation index showed 200-300 in 22 eases, and ~200 in the other 29 cases. Chest X-ray showed mainly signs of exudate with patchy, ground glass, reticular and nodular changes in bilateral lungs. The lesions became worse and fused rapidly. Bilateral disease was identified in 94.1 % of the 51 patients. Fifteen patients died. The mortality rate was 29.4% （15/51）. All death cases had acute respiratory distress syndrome （ARDS）. About 51. 7% of ARDS patients died. Underlying disease was found in 10 cases, about 66.7% of the death cases. Forty-one patients （41/51） received treatment with methylprednisolone, 28 survived. The diagnosis was confirmed in 6 cases, including invasive pulmonary aspergillosis （3）, and influenza A H1N1 （3）. The serum antibody assay was positive for human immunodeficiency virus in 6 cases. The serum antibody test was negative for Chlamydia, Mycoplasma or Legionella in all cases. Of the 6 cases positive for fungal culture, G-test was positive in 2 cases, but GM test was negative in all cases. Serology test for viral infection （cytomegalovirus, adenovirus, and respiratory syncytial virus） was carried out in 32 cases. IgG antibody against cytomegalovirus was positive in 9 cases. Conclusions It is a tough challenge to reveal the etiology of acute lung injury resulted from severe pneumonia. Underlying diseases may be associated with the prognosis of severe pneumonia. Early use of corticosteroids is helpful for favorable outcome of acute lung injury.