kaolinite and Pleural-Diseases

Due to the lack of consensus in the literature in the use of posteroanterior (PA) vs PA with right and left oblique views as the optimum radiograph surveillance methodology to investigate pleural changes, a study was undertaken to evaluate the reliability, sensitivity, and specificity of these two approaches.. Three experienced radiologist B readers used the 1980 International Labor Office classification system for pneumoconiosis to independently read chest radiographs of workers with individual identifiers masked. All radiographs were read first as a PA view only. Unknown to the B readers, each subject's PA was then matched to his or her corresponding right and left oblique views (film triad) and re-read several weeks later.. The respiratory health of 652 workers exposed to refractory ceramic fiber was assessed as part of cross-sectional and longitudinal surveillance programs.. kappa Statistics for interreader and intrareader reliability between the PA view and film triad methods were calculated. Sensitivity, specificity, and positive predictive value were assessed by comparing the initial cross-sectional study to the longitudinal study. The film triad method had considerably higher interreader reliability (kappa = 0.59) compared to the PA-only method (kappa = 0.44). Results from the initial cross-sectional study were then compared to findings evaluated longitudinally. The film triad again was superior, demonstrating a positive predictive value of 73.7% compared to only 47.8% for the PA method.. It is our recommendation that the film triad method be used in surveillance studies where both parenchymal and pleural changes are anticipated.

Topics: Ceramics; Cross-Sectional Studies; Follow-Up Studies; Humans; Kaolin; Longitudinal Studies; Mineral Fibers; Observer Variation; Occupational Diseases; Pleura; Pleural Diseases; Predictive Value of Tests; Radiography, Thoracic; Sensitivity and Specificity

Kaolin is found along the "fall line" in Georgia, and parenchymal changes, both simple and complicated pneumoconiosis, have been previously described. This study was done to determine whether pleural thickening occurs in workers with mild kaolin pneumoconiosis.. We evaluated 350 workers at a kaolin plant in Georgia. Thirty-two workers with abnormal chest radiographs were clinically evaluated. Twelve workers with mild kaolinosis but without any evidence of pleural changes on chest roentgenograms had computed tomography (CT) of the chest to assess the presence of pleural thickening.. Nineteen workers had radiographic changes consistent with kaolin pneumoconiosis (prevalence 5.4%), and four workers had evidence of pleural plaques (prevalence 1.1%). Five of the 12 workers had evidence of pleural thickening on CT.. This study shows that pleural thickening may be common on chest tomography in workers with kaolinosis and that the exposure to kaolin dust should be considered in the differential diagnosis of pleural thickening.

Topics: Adult; Diagnosis, Differential; Dust; Georgia; Humans; Kaolin; Lung Diseases, Obstructive; Middle Aged; Mining; Occupational Exposure; Pleural Diseases; Pneumoconiosis; Prevalence; Pulmonary Fibrosis; Radiography, Thoracic; Tomography, X-Ray Computed

Topics: Aluminum Silicates; Humans; Kaolin; Pleural Diseases; Pneumothorax