A Useful Parameter for Distinguishing between Pleural Exudates and Transudates (7)

A Useful Parameter for Distinguishing between Pleural Exudates and Transudates (7)A few recent studies of its value for distinguishing transudates from exudates” have obtained good results but have involved only small numbers of patients. In this study, we considered a total of 253 patients, 65 with transudates and 188 with exudates.
We found PCHOL levels of 28.5 ±12.8 mg/dl in transudates, 88.1 ±30 mg/dl in neoplastic exudates, 96.5 ± 28 mg/dl in tuberculous exudates, and 88 ± 35.9 mg/dl in the miscellaneous exudate group. With a classifying threshold of 55 mg/dl, PCHOL had a ;ensitivity of 91 percent and a specificity of 100 percent or diagnosis of exudates, with a PPV of 100 percent. With a classifying threshold of 0.3, P/SCHOL had a iensitivity of 92.5 percent and a specificity of 87.6 percent. Both PCHOL and P/SCHOL misclassified ewer cases than any of Light’s parameters (Table 3), vhich confirms our previous findings and those of others.
Although it is well known that cholesterol levels are ligh in pseudochylothorax, only one of our cases was >f this kind (a case of rheumatoid arthritis with a PCHOL of 242 mg/dl and P/SCHOL of 2.3). Although :he macroscopic appearance of pleural fluid is not ihvays a sufficient basis on which to exclude pseudochylothorax, our fluid was milky due to the accumulation of cholesterol released from degenerate cells. For pseudochylothorax to develop requires that the fluid remain in the pleural cavity for years.