It has been suggested previously that pleural biopsy will be a rewarding procedure in patients suspected. of having malignancy or granulomatous pleural disease. However, the reliability of clinical suspicion will vary depending on the expertise of the physician. To facilitate the recognition of patients in whom this procedure is likely to yield a specific diagnosis, we advocate combining all five objective criteria identified in this study into a single test which is positive when any criterion is present. When used in this manner, the criteria are extremely sensitive, as 97 percent of the patients with either cancer or granulomatous pleuritis had at least one criterion (Fig 2). buy levlen online
The predictive value of the combined criteria was a modest 74 percent, however, since many of the patients with nonspecific pleuritis who underwent pleural biopsy also had at least one criterion. When two or more criteria were present, the positive predictive value was 90 percent, indicating a strong likelihood of obtaining a definitive diagnosis by biopsy. The real value of the criteria may lie in sparing patients with nonspecific pleuritis the morbidity and expense of a pleural biopsy since their negative predictive value was 94 percent, ie, the likelihood of diagnosing either malignancy or granulomatous pleuritis in the absence of any criterion was only 6 percent. Thirty-one of the 33 patients who did not have any criterion had a final diagnosis of nonspecific pleuritis (Fig 2).
Based on our observations, we recommend the following diagnostic approach to the evaluation of an unexplained exudative pleural effusion. If the initial pleural biopsy reveals only nonspecific pleuritis in a patient without any of the five criteria, further pleural biopsies are not performed, and the patient is followed clinically. However, even when none of the criteria is present, bronchoscopy may be indicated if the patient has hemoptysis or if the chest roentgenogram reveals an undiagnosed parenchymal abnormality. Pulmonary embolism is a common cause of exudative effusions that should be excluded by lung scanning before the diagnosis of idiopathic nonspecific pleuritis is accepted. In the presence of any one clinical criterion, a second pleural biopsy and/or bronchoscopy is performed. If both of these procedures fail to identify a specific etiology, the patient is followed clinically. When two or more criteria are present, an aggressive diagnostic approach including repeat pleural biopsy, bronchoscopy, and if required, open pleural biopsy is recommended.