[Autopsy case of diffuse pleural thickening presenting respiratory impairment and benign asbestos pleurisy]

A 51-year-old man presented with back pain in 1997. He had a 30-year-history of occupational asbestos exposure. His chest CT showed bilateral pleural thickening and pleural effusion. The pleural effusion of the right thorax exhibited both elevated level of adenosine deaminase and increased numbers of lymphocytes. Antituberculous chemotherapy had no effect on the exudates. Progressive bilateral pleural thickening were found on chest CT, and pulmonary function tests showed severe restrictive ventilatory impairments since 1998. Thoracoscopic pleural biopsy was conducted in 2001 to exclude pleural malignant mesothelioma. No malignancy was found in pleural samples. After 3-year observation and excluding other causes, he was given a diagnosis of benign asbestos pleurisy. In 2005, fibrotic changes were found in both lower lung fields in chest CT. He suffered from respiratory failure with carbon dioxide retention, and died in 2006. The autopsy disclosed asbestos-related lung diseases. We suspected that diffuse pleural thickening could be a major cause of fatal respiratory impairment in this case.