title: Matrix metalloproteinase levels in the differentiation of parapneumonic pleural effusions.
abstract: BACKGROUND
  Matrix metalloproteinases (MMPs) have been implicated in the escalation of fibrosis and remodeling which are central to the subsequent progression of a parapneumonic pleural effusion to empyema.
  
  
  OBJECTIVE
  The aim of this study was the assessment of MMP-2, MMP-8 and MMP-9 in parapneumonic pleural effusions in order to examine their value in the differentiation between uncomplicated and complicated parapneumonic effusions.
  
  
  METHODS
  The study included 208 consecutive patients with pleural effusions [60 parapneumonic (27 uncomplicated parapneumonic, 17 complicated parapneumonic, 16 empyemas), 24 tuberculous, 89 malignant and 35 transudates]. Concentrations of pleural fluid and serum MMP-2, MMP-8 and MMP-9 were determined by immunoassay.
  
  
  RESULTS
  Pleural fluid MMP-8 and MMP-9 levels were higher in complicated parapneumonic effusions or empyema than in uncomplicated effusions, while their serum levels were higher in complicated parapneumonic effusions. MMP-2 levels were higher in uncomplicated than in complicated parapneumonic effusions or empyema. Pleural fluid MMP-2/MMP-9 ratio was the best marker to differentiate complicated from uncomplicated parapneumonic effusions, with a sensitivity of 94.1% and a specificity of 77.8% at a cut-off point of 1.32 (AUC = 0.887).
  
  
  CONCLUSIONS
  Pleural fluid MMP-2, MMP-8 and MMP-9 may provide useful information for differentiating between uncomplicated and complicated parapneumonic effusions.
authors.affiliation: Respiratory Medicine Department, University of Thessaly Medical School, Larissa, Greece.
authors.forename: Smaragda
authors.initials: S
authors.lastname: Oikonomidi
authors.forename: Konstantinos
authors.initials: K
authors.lastname: Kostikas
authors.forename: Ioannis
authors.initials: I
authors.lastname: Kalomenidis
authors.forename: Irene
authors.initials: I
authors.lastname: Tsilioni
authors.forename: Christos
authors.initials: C
authors.lastname: Daenas
authors.forename: Konstantinos I
authors.initials: KI
authors.lastname: Gourgoulianis
authors.forename: Theodoros S
authors.initials: TS
authors.lastname: Kiropoulos
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood; D003937:Diagnosis, Differential; D016724:Empyema, Pleural / Q000097:blood / Q000175:diagnosis; D045604:Extracellular Fluid / Q000378:metabolism; D005260:Female; D006801:Humans; D008297:Male; D020778:Matrix Metalloproteinase 2 / Q000097:blood*; D020784:Matrix Metalloproteinase 8 / Q000097:blood*; D020780:Matrix Metalloproteinase 9 / Q000097:blood*; D008875:Middle Aged; D010996:Pleural Effusion / Q000097:blood* / Q000150:complications / Q000175:diagnosis; D011014:Pneumonia / Q000097:blood / Q000175:diagnosis
chemical_list: D015415:Biomarkers; C522361:MMP2 protein, human; D020778:Matrix Metalloproteinase 2; C488762:MMP8 protein, human; D020784:Matrix Metalloproteinase 8; D020780:Matrix Metalloproteinase 9