The usefulness of cholesterol determination in the etiology of pleural effusion

: 95 pleural effusions of different etiology were studied. 25 were transudate, 22 neoplastic, 28 caused by tuberculosis, and 20 miscellaneous. The Light parameters (pleural protein/plasma) (Prot LP/P), Pleural LDH (LDH LP) and LDH pleural/plasma quotient (LDH LP/P) were determined and compared with the efficacy of pleural cholesterol (Chol LP) and pleural cholesterol/plasma quotient (Chol LP/P) to differentiate the transudate from pleural exudate. With Prot LP/P quotient the sensitivity was of 85% and the specificity 91.6%; with LDH LP the sensitivity was of 74.6% and the specificity 97.6%. With the LDH LP/P quotient the sensitivity was of 89% and the specificity 87.8%. The sensitivity of each parameter was similar to that obtained by Light but less specific. All the transudates had levels of chol LP lower than 55 mq/dl (100% specificity) with a sensitivity of 84%. The Chol LP/P quotient had a limit of 0.3, this being its sensitivity of 91.3% and 93.1% its specificity. The presence of both parameters were necessary to the classification and the sensitivity obtained being of 80.3% and the specificity 100%. We concluded that the determinations of Chol LP and the Chol LP/P quotient are of great advantage in differentiating the pleural transudate from pleural exudate and the predictive value is, at least, similar to that obtained by Light.