In order to establish the value and diagnostic significance of the clinical and laboratory tests that may be considered early signs of asbestosis, an introductory review analyzes the relationships between these tests (asbestos bodies and siderocytes in the sputum, small crepitating rales, restrictive ventilatory insufficiency and impairment of alveolar-capillary diffusion) and the morphological alterations induced by asbestos in the lung tissue. In a group of 182 subjects, the frequency of positive response of such 'non-radiological indicators of asbestosis' was evaluated in relation to the degree and duration of risk and the time elapsed since the beginning of exposure; the relationship between association of the various indicators and occupational hazard was also examined and the predictive value of disease was established for each indicator and for associations of indicators. The frequency of positive response of the indicators was significantly correlated with the intensity of exposure to asbestos, with a latency period that can be calculated in the order of several years after beginning of exposure. Among the indicators, asbestos bodies, siderocytes, small rales, and restrictive ventilatory insufficiency showed a correlation that was linear with the intensity of hazard, whereas impairment of alveolar-capillary diffusion, which when present always appeared early, behaved more haphazardly: this seems to be in relation to the fact that sclerosis of the large interstice, even though constant and early in appearance, may vary in distribution from one subject to another. The predictive value of the individual indicators and of associations of several indicators was very high: when determinations are carried out using the correct methods and the results are correctly evaluated, the presence of pulmonary lesions due to asbestos can be diagnosed in 90% of the cases, independently of the results of radiological examination. Therefore, the periodic surveillance of workers must always include examinations to detect asbestos bodies and siderocytes in the sputum, small crepitating rales, functional alterations consisting of restrictive ventilatory insufficiency and/or impairment of alveolar-capillary diffusion: the results must be considered together in a single concise judgement, bearing in mind the type of lesion that induces positive response of each parameter. Compared to the data obtained with radiological examination, much more accurate information can be gained from these indicators on the possible presence of initial pulmonary lesions.
|Translated title of the contribution||Asbestosis: Evaluation of non-radiological indicators|
|Number of pages||17|
|Journal||Medicina del Lavoro|
|Publication status||Published - 1978|
ASJC Scopus subject areas
- Public Health, Environmental and Occupational Health