Asbestos-related pleural diseases: Dimensional criteria are not appropriate to differentiate diffuse pleural thickening from pleural plaques

• Published in: American journal of industrial medicine 2004-03, Vol.45 (3), p.289-296
• Main Authors: Ameille, Jacques, Matrat, Mireille, Paris, Christophe, Joly, Nathalie, Raffaelli, Claude, Brochard, Patrick, Iwatsubo, Yuriko, Pairon, Jean Claude, Letourneux, Marc
• Format: Article
• Language: English
• Subjects: asbestos; Asbestos - toxicity; Asbestosis - classification; Asbestosis - diagnostic imaging; Biological and medical sciences; Chemical and industrial products toxicology. Toxic occupational diseases; Chest Pain - etiology; diffuse pleural thickening; Dyspnea - etiology; Female; France; Humans; ILO classification; Inorganic dusts (pneumoconiosises) and organic dusts (byssinosis etc.); Male; Medical sciences; Middle Aged; Pleural Diseases - diagnostic imaging; Pleural Diseases - etiology; pleural plaques; Respiratory Function Tests; Retrospective Studies; Sputum - secretion; Tomography, X-Ray Computed; Toxicology
• ISSN: 0271-3586; 1097-0274
• DOI: 10.1002/ajim.10341

Background In the literature, the criteria used to define pleural plaques (PP) and diffuse pleural thickening (DPT) are very heterogeneous and often imprecise. A multicenter restropective study was conducted to assess the relevance of two radiographic definitions of DPT. Methods The study population consisted of 287 subjects with asbestos‐related pleural thickening. Two definitions were used to characterize DPT on postero‐anterior chest radiographs: definition 1: pleural thickening associated with obliteration of the costophrenic angle; definition 2: pleural thickening at least 5 mm wide, extending for more than one quarter of the chest wall. Prevalence of respiratory symptoms and pulmonary function tests were compared in the DPT and PP groups resulting from the two definitions of DPT. Results According to definition 1, 34 patients (11.8%) were classified in the DPT group. Prevalence of chronic sputum, dyspnea, and chest pain was significantly higher in this group than in the PP group. FEV1, FVC, and TLC were significantly lower. The differences persisted after adjustment for confounding factors. According to definition 2,102 patients (36.6%) were classified in the DPT group. DPT and PP groups did not differ in terms of prevalence of respiratory symptoms, or pulmonary function tests. Agreement between readers was significantly better when using definition 1. Conclusions Obliteration of costophrenic angle is a much more reliable sign than dimensional criteria to characterize DPT. Am. J. Ind. Med. 45:289–296, 2004. © 2004 Wiley‐Liss, Inc.