title: Diagnosis of tuberculous pleuritis by the measurement of soluble interleukin 2 receptor in pleural fluid.
abstract: OBJECTIVE
  As soluble interleukin-2 receptor (sIL-2R) is a marker of T-lymphocyte activation, we sought to determine whether its measurement in pleural fluid is diagnostically useful in tuberculous pleurisy.
  
  
  METHODS
  We compared the concentrations of sIL-2R in pleural samples of 23 patients with tuberculous pleurisy and 109 patients with non-tuberculous effusions (34 malignant, 34 parapneumonic, 27 transudates and 14 miscellaneous). sIL-2R was measured by a commercial ELISA test and its performance was evaluated using receiver operating characteristic (ROC) analysis.
  
  
  RESULTS
  The mean values of pleural sIL-2R were 9179 U/mL in patients with tuberculous pleurisy vs 3664 U/mL in patients with malignancy, 2603 U/mL in patients with parapneumonic effusions, 1016 U/mL in patients with transudates, and 1906 U/mL in patients with miscellaneous diseases (P < 0.0001). A ROC curve identified the best cut-off at 4700 U/mL, yielding measures for sensitivity (0.91), specificity (0.94) and accuracy (0.94).
  
  
  CONCLUSIONS
  The results of this pilot study suggest that pleural sIL-2R appears to be clinically useful for differentiating between tuberculous and non-tuberculous pleural effusions.
authors.affiliation: Department of Internal Medicine, University Hospital Arnau de Vilanova, University of Lleida, Spain. jporcelp@medynet.com
authors.forename: J M
authors.initials: JM
authors.lastname: Porcel
authors.forename: I
authors.initials: I
authors.lastname: Gázquez
authors.forename: M
authors.initials: M
authors.lastname: Vives
authors.forename: B
authors.initials: B
authors.lastname: Pérez
authors.forename: M
authors.initials: M
authors.lastname: Rubio
authors.forename: M C
authors.initials: MC
authors.lastname: Rivas
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000032:analysis; D003937:Diagnosis, Differential; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D010996:Pleural Effusion / Q000382:microbiology*; D015375:Receptors, Interleukin-2 / Q000032:analysis*; D012680:Sensitivity and Specificity; D014396:Tuberculosis, Pleural / Q000175:diagnosis* / Q000382:microbiology
chemical_list: D015415:Biomarkers; D015375:Receptors, Interleukin-2