title: Biochemical and cytologic characteristics of pleural effusions secondary to pulmonary embolism.
abstract: OBJECTIVE
  To characterize the biochemical and cytologic constituents of pleural effusions secondary to pulmonary embolism.
  
  
  METHODS
  A descriptive clinical study.
  
  
  METHODS
  A community teaching hospital with 750 beds, which acts as a tertiary referral center for several subspecialties.
  
  
  METHODS
  Patients with pleural effusions secondary to pulmonary embolism who underwent diagnostic thoracentesis during the last 7 years were retrospectively studied. Pleural fluid mesothelial hyperplasia was revised and compared with that found in patients with pleural effusions of different origin.
  
  
  RESULTS
  Pleural effusions from all 60 patients with pulmonary embolism were exudates, and in 40 patients (67%) contained erythrocyte counts > 10,000/microL. A bloody appearance was not related to the use of anticoagulant therapy before thoracentesis. Polymorphonuclear leukocytes were predominant in 36 patients (60%); in 11 patients (18%), a proportion of eosinophils > 10% was found. Mesothelial hyperplasia was significantly higher in patients with pulmonary embolism than in patients in the control group (p < 0.01).
  
  
  CONCLUSIONS
  In the absence of trauma, a bloody or eosinophilic effusion with a marked mesothelial hyperplasia should prompt a workup to rule out embolism. The finding of transudative pleural fluid chemistries in these patients should not be assumed to be secondary to embolism before ruling out other causes of transudative effusion.
authors.affiliation: Hospital General Universitario de Alicante, Alicante, Spain. romero_san@gva.es
authors.forename: Santiago
authors.initials: S
authors.lastname: Romero Candeira
authors.forename: Luis
authors.initials: L
authors.lastname: Hernández Blasco
authors.forename: Maria J
authors.initials: MJ
authors.lastname: Soler
authors.forename: Alejandro
authors.initials: A
authors.lastname: Muñoz
authors.forename: Ignacio
authors.initials: I
authors.lastname: Aranda
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004804:Eosinophils / Q000473:pathology; D004906:Erythrocyte Count; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010996:Pleural Effusion / Q000209:etiology / Q000378:metabolism / Q000473:pathology*; D011655:Pulmonary Embolism / Q000150:complications*; D012189:Retrospective Studies