SARS多脏器穿刺组织病理学及超微结构的研究

A STUDY OF PATHOLOGY AND ULTRAMICROSTRUCTURE OF NEEDLE-BIOPSY SPECIMENS OF MULTIPLE ORGANS OF SARS PATIENTS

目的 探讨严重急性呼吸综合征 (SARS)病理学改变和超微结构特点及其与临床病程的关系。方法 应用光镜、组织化学、透射电镜、免疫组化和间接免疫荧光法对病程为 3～ 5周的 4例中晚期SARS死亡病例多器官穿刺组织 (肺脏、心脏、肝脏、脾脏、肾脏、胰腺、胃)进行研究。结果 SARS死亡病例肺部病理改变以肺泡间质纤维增生和肺泡早期纤维化等机化性肺炎表现为主要特征 ,同时有弥漫性肺泡损伤和脱屑性肺炎改变。脾脏内CD3和CD2 0阳性淋巴细胞减少 ,CD6 8阳性的组织细胞和S 10 0阳性的树突状细胞增多。骨髓粒细胞系统增生减退。在肺泡Ⅱ型上皮细胞、血管内皮细胞和脾脏淋巴细胞胞质内可见多种类型的冠状病毒样颗粒 ,大小均为 6 0～2 2 0nm ,有包膜 ,表面似有纤突样结构 ,以具有同心圆外膜、低电子密度核心的A型病毒颗粒和具有高电子密度核心的C型病毒颗粒为多见。间接免疫荧光法血清检测 4例病人SARS病毒IgGAb均呈明确阳性反应。结论 SARS是由新型冠状病毒引起的急性呼吸道传染病 ,主要靶器官是肺脏和免疫器官。SARS不同病程死亡病人的肺部病理学改变有不同的特征。

Objective To study the pathological and ultramicrostructural characteristics of organ tissues in relation to the clinical course of severe acute respiratory syndrome (SARS). Methods Post-mortem tissue samples of organs (lungs, heart, liver, spleen, kidneys, pancreas, stomach ) were obtained by needle biopsy from four SARS patients who died in middle and late stages 3-5 weeks after the onset of the disease. The pathological samples were studied by light and electron microscope, immunohistochemistry, histochemistry and indirect immuno-fluorescent antibody test. Results The main pathological features were early interstitial pulmonary fibrosis or organizing pneumonia. Fibroblasts were increased in the interalveoli septa and young connective tissue was found to fill the alveoli. Diffuse alveolar damage (DAD) with alveolar pneumocytes proliferation and an increase in macrophages were found. Desquamative alveolitis also existed at the same time. Squamous metaplasia and syncytial giant cells with multinuclei could be seen. CD3 + and CD20 + lymphocytes were markedly decreased and CD68 + macrophages and S-100 + dendritic cells increased in spleen. Proliferation of bone marrow cells became restrained . Hepatocytes were vacuolated with fatty degeneration. Electron microscopy showed the presence of coronavirus-like particles 80-60nm in diameter enveloped in the cytoplasm of the type Ⅱ pneumocytes, endothelial cells and lymphocytes. Conclusions A novel coronavirus is the cause of the newly recognized severe acute respiratory syndrom (SARS). The main target organs are lung and immune system. Different pulmonary pathological features were found in patients dying from the disease in different stages. All of specimens showed positive reaction of SARS-fluorescence antibody.