title: Cautious application of pleural N-terminal pro-B-type natriuretic peptide in diagnosis of congestive heart failure pleural effusions among critically ill patients.
abstract: OBJECTIVE
  Several studies on diagnostic accuracy of pleural N-terminal pro-B-type natriuretic peptide (NT-pro-BNP) for effusions from congestive heart failure (CHF) conclude that pleural NT-pro-BNP is a useful biomarker with high diagnostic accuracy for distinguishing CHF effusions. However, its applicability in critical care settings remains uncertain and requires further investigations.
  
  
  METHODS
  NT-proBNP was measured in pleural fluid samples of a prospective cohort of intensive care unit patients with pleural effusions. Receiver operating characteristic curve analysis was performed to determine diagnostic accuracy of pleural NT-proBNP for prediction of CHF effusions.
  
  
  RESULTS
  One hundred forty-seven critically ill patients were evaluated, 38 (26%) with CHF effusions and 109 (74%) with non-CHF effusions of various causes. Pleural NT-proBNP levels were significantly elevated in patients with CHF effusions. Pleural NT-pro-BNP demonstrated the area under the curve of 0.87 for diagnosing effusions due to CHF. With a cutoff of 2200 pg/mL, pleural NT-proBNP displayed high sensitivity (89%) but moderate specificity (73%). Notably, 29 (27%) of 109 patients with non-CHF effusions had pleural NT-proBNP levels >2200 pg/mL and these patients were more likely to experience septic shock (18/29 vs. 10/80, P<0.001) or acute kidney injury (19/29 vs. 9/80, P<0.001).
  
  
  CONCLUSIONS
  Among critically ill patients, pleural NT-proBNP measurements remain a useful diagnostic aid in evaluation of pleural effusions. However, patients with non-CHF effusions may exhibit high pleural NT-proBNP concentrations if they suffer from septic shock or acute kidney injury. Accordingly, it is suggested that clinical context should be taken into account when interpreting pleural NT-proBNP values in critical care settings.
authors.affiliation: Department of Neurology, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan.
authors.forename: Jiann-Horng
authors.initials: JH
authors.lastname: Yeh
authors.affiliation: Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan; Department of Traumatology, National Taiwan University Hospital, Taipei, Taiwan; Graduate Institute of Clinical Medicine, National Taiwan University, Taipei, Taiwan.
authors.forename: Chun-Ta
authors.initials: CT
authors.lastname: Huang
authors.affiliation: Graduate Institute of Clinical Medicine, National Taiwan University, Taipei, Taiwan; Department of Surgery, National Taiwan University Hospital, Taipei, Taiwan.
authors.forename: Chia-Hsiung
authors.initials: CH
authors.lastname: Liu
authors.affiliation: Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan.
authors.forename: Sheng-Yuan
authors.initials: SY
authors.lastname: Ruan
authors.affiliation: School of Medicine, College of Medicine, Fu-Jen Catholic University, New Taipei, Taiwan.
authors.forename: Yi-Ju
authors.initials: YJ
authors.lastname: Tsai
authors.affiliation: Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan.
authors.forename: Ying-Chun
authors.initials: YC
authors.lastname: Chien
authors.affiliation: Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan.
authors.forename: Ching-Yao
authors.initials: CY
authors.lastname: Yang
authors.affiliation: Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan.
authors.forename: Chun-Kai
authors.initials: CK
authors.lastname: Huang
authors.affiliation: Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan.
authors.forename: Chia-Lin
authors.initials: CL
authors.lastname: Hsu
authors.affiliation: Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan.
authors.forename: Lu-Cheng
authors.initials: LC
authors.lastname: Kuo
authors.affiliation: Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan.
authors.forename: Pei-Lin
authors.initials: PL
authors.lastname: Lee
authors.affiliation: Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan.
authors.forename: Shih-Chi
authors.initials: SC
authors.lastname: Ku
authors.affiliation: Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan.
authors.forename: Ping-Hung
authors.initials: PH
authors.lastname: Kuo
authors.affiliation: Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan.
authors.forename: Chong-Jen
authors.initials: CJ
authors.lastname: Yu
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000378:metabolism; D015331:Cohort Studies; D016638:Critical Illness; D005260:Female; D006333:Heart Failure / Q000175:diagnosis* / Q000378:metabolism* / Q000473:pathology; D006801:Humans; D008297:Male; D020097:Natriuretic Peptide, Brain / Q000378:metabolism*; D010446:Peptide Fragments / Q000378:metabolism*; D010996:Pleural Effusion / Q000209:etiology* / Q000378:metabolism / Q000473:pathology; D011446:Prospective Studies; D013624:Taiwan
chemical_list: D015415:Biomarkers; D010446:Peptide Fragments; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain