Roggli V L
Department of Pathology, Durham Veterans Administration Medical Center, North Carolina 27710.
Scanning Microsc. 1991 Mar;5(1):71-80; discussion 80-3.
The mineral fiber content of lung parenchyma in 24 cases of diffuse pulmonary fibrosis of unknown cause was determined by scanning electron microscopy and compared with that of 36 autopsy cases of histologically confirmed asbestosis and 20 autopsy cases of patients with normal lungs. Fibers were isolated from the lung using a hypochlorite digestion technique and collected on the surface of a polycarbonate filter. In addition, the types of fibers present (asbestos vs. other mineral fibers) were determined by energy dispersive x-ray analysis (EDXA). When the histologic grade of fibrosis in the cases of asbestosis was compared with the uncoated fiber content by means of linear regression analysis, it was determined that the fiber content of the 24 cases of diffuse pulmonary fibrosis of unknown cause was below the 95% confidence limit for asbestosis in every instance. Furthermore, the majority of fibers analyzed by EDXA were not asbestos in the cases with diffuse pulmonary fibrosis of unknown cause, whereas more than 90% of the fibers from the asbestosis cases were commercial amphiboles (amosite or crocidolite). It was concluded that most patients with advanced pulmonary fibrosis whose tissue samples do not meet histologic criteria for asbestosis do not have asbestos-induced fibrosis, even though there may be some history of exposure to asbestos. In such cases, scanning electron microscopic analysis of mineral fiber content and EDXA of the types of fibers present often provide useful information with regard to the correct classification of these cases.
采用扫描电子显微镜测定了24例原因不明的弥漫性肺纤维化患者肺实质的矿物纤维含量，并与36例经组织学确诊为石棉沉着病的尸检病例以及20例肺正常的尸检病例进行了比较。使用次氯酸盐消化技术从肺中分离出纤维，并收集在聚碳酸酯滤膜表面。此外，通过能量色散X射线分析（EDXA）确定存在的纤维类型（石棉与其他矿物纤维）。通过线性回归分析比较石棉沉着病病例的纤维化组织学分级与未包被纤维含量时，发现24例原因不明的弥漫性肺纤维化病例的纤维含量在每种情况下均低于石棉沉着病的95%置信限。此外，在原因不明的弥漫性肺纤维化病例中，经EDXA分析的大多数纤维不是石棉，而石棉沉着病病例中超过90%的纤维是商业闪石（铁石棉或青石棉）。得出的结论是，大多数晚期肺纤维化患者的组织样本不符合石棉沉着病的组织学标准，即使可能有一些接触石棉的病史，也不是石棉所致纤维化。在这种情况下，对矿物纤维含量进行扫描电子显微镜分析以及对存在的纤维类型进行EDXA分析，往往能为这些病例的正确分类提供有用信息。
