Asbestos bodies and fibers identification in pulmonary tissue recovered from post-mortem examinations: an update

BACKGROUND: The diagnosis of asbestos-related diseases remains sometimes controversial even if clinical-instrumental, documental-circumstantial and histopathological data are revised. A unique, standardized, shared and accurate procedure to quantify asbestos bodies (AB) and fibers still lacks. In this study, an update of the Smith & Naylor method is presented, aiming to possibly solve some of the original procedure’s limits. METHODS: As questionable cases represent a major challenge in the clinical everyday setting, 2 controls and 5 subjects with possible or certain exposure to asbestos were selected. Samples of autoptic pulmonary tissue (0.7 g formalin-fixed) were digested and analyzed through optical (OM) and electron microscopy (SEM). Type of asbestos exposure, obtained from interviews and clinical records’ review, was compared with the estimation of asbestos-related disease, applying Helsinki criteria after the OM-SEM analysis. Analysis of multiple areas of a single lung were additionally performed and used to assess the reproducibility of the results. RESULTS: Exposure as obtained from clinical records and work-related history matched with the OM-SEM analysis results in five of seven cases. One control tested positive to asbestos fibers, outlining the need for a deeper investigation. One case of malignant mesothelioma and with possible exposure to asbestos revealed no AB. In repetitive measures, the highest AB count was 1.81 bigger than lower, but standard deviation appeared acceptable. CONCLUSIONS: The updated Smith & Naylor appears to be a rather easy, inexpensive and reliable method to quantify AB and to diagnose asbestos-related diseases, especially in the absence or discrepancy between clinical data and past history.