title: Useful tests on pleural fluid that distinguish transudates from exudates.
abstract: We aimed to compare the classic Light's criteria with different testing strategies in an effort to improve the accuracy of pleural fluid (PF) categorization. Thirty-two patients with transudates and 140 with exudates on the basis of their clinical diagnosis were entered into the study. We examined the discriminative properties of 10 analytes in the identification of PF, both singly and in combination with an 'or' rule, to see which was best in distinguishing a transudate from an exudate. A combination of PF lactate dehydrogenase (LD) > 307 U/L (two-thirds of the upper limit of the serum LD reference range) with either PF cholesterol > 1.55 mmol/L or PF to serum protein ratio > 0.5 had a diagnostic accuracy similar to that of Light's criteria. We suggest the use of PF LD and cholesterol in combination as an alternative method for distinguishing pleural transudates from exudates. This test combination avoids the need for venepuncture and the simultaneous collection of a blood sample.
authors.affiliation: Department of Internal Medicine, University Hospital Arnau de Vilanova, Lleida, Spain. jporcelp@medynet.com
authors.forename: J M
authors.initials: JM
authors.lastname: Porcel
authors.forename: M
authors.initials: M
authors.lastname: Vives
authors.forename: M C
authors.initials: MC
authors.lastname: Vicente de Vera
authors.forename: G
authors.initials: G
authors.lastname: Cao
authors.forename: M
authors.initials: M
authors.lastname: Rubio
authors.forename: M C
authors.initials: MC
authors.lastname: Rivas
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002784:Cholesterol / Q000032:analysis; D019963:Clinical Chemistry Tests; D003937:Diagnosis, Differential; D005122:Exudates and Transudates / Q000737:chemistry*; D005260:Female; D006801:Humans; D007770:L-Lactate Dehydrogenase / Q000032:analysis; D008297:Male; D008875:Middle Aged; D010996:Pleural Effusion / Q000737:chemistry* / Q000175:diagnosis*; D011446:Prospective Studies; D011506:Proteins / Q000032:analysis
chemical_list: D011506:Proteins; D002784:Cholesterol; D007770:L-Lactate Dehydrogenase