What is the significance of non‐specific pleuritis? A trick question

Non‐specific pleuritis (NSP) is defined as fibrinous or inflammatory pleuritis which cannot be attributed to a specific benign or malignant etiology. It can be diagnosed in biopsies in up to 30% of cases of exudative pleuritis after thoracoscopy, with a mean of 19.2%. In 66 out of 469 (14.2%) patients in combined series, a malignant pleural disease (mostly mesothelioma) was found during a follow‐up of at least 21 months. Most likely, a follow‐up...