title: Differentiation of pulmonary embolism from high altitude pulmonary edema.
abstract: OBJECTIVE
  To differentiate the high altitude pulmonary edema (HAPE) from pulmonary embolism (PE) by clinical probability model of PE, lactate dehydrogenase (LDH), aspartate transaminase (AST) and D-dimer assays at high altitude.
  
  
  METHODS
  A prospective study.
  
  
  METHODS
  The study was carried out at CMH, Skardu, from October 2001 to December 2002.
  
  
  METHODS
  Consecutive 40 patients evacuated from height > 3000 meters with symptoms of PE or HAPE were included. Clinical pretest probabilities scores of PE, Minutex D-dimer assay (Biopool international) and cardiac enzymes estimation by IFCC approved methods, were used for diagnosis. Mann-Whitney U test was applied by using SPSS and level of significance was taken at (p<0.05).
  
  
  RESULTS
  Out of 40 subjects, 31 HAPE and 9 patients of PE were initially diagnosed on the basis of clinical features, D-dimer assay and V-Q scanning. Out of 9 patients of PE; 3 had plasma D-dimer between 250-500 ng/ml and 6 > 500 ng/ml. Plasma D-dimer of 500 ng/ml was considered as cut-off value; 6 (66.7%) patients of PE could be diagnosed and 30 (96.7%) cases of HAPE excluded indicating very good negative predictive value. Serum LDH, AST and CK were raised above the reference ranges in 8 (89%), 7 (78 %) and 3 (33 %) patients of PE as compared to 11 (35%), 6 (19%) and 9 (29 %) of HAPE respectively.
  
  
  CONCLUSIONS
  Clinical assessment in combination with D-dimer assay, LDH and AST can be used for timely differentiation of PE from HAPE at high altitude where diagnostic imaging procedures are not available.
authors.affiliation: Department of Pathology, Combined Millitary Hospital, Skardu. dilshad56@yahoo.com
authors.forename: Dilshad Ahmed
authors.initials: DA
authors.lastname: Khan
authors.forename: Rizwan
authors.initials: R
authors.lastname: Hashim
authors.forename: Tariq Mahmud
authors.initials: TM
authors.lastname: Mirza
authors.forename: Muhammad Matloob ur
authors.initials: MM
authors.lastname: Rahman
mesh_terms: D000328:Adult; D000531:Altitude; D000532:Altitude Sickness / Q000175:diagnosis*; D001219:Aspartate Aminotransferases / Q000097:blood; D003937:Diagnosis, Differential; D005338:Fibrin Fibrinogen Degradation Products / Q000032:analysis*; D006801:Humans; D007770:L-Lactate Dehydrogenase / Q000097:blood; D008168:Lung / Q000000981:diagnostic imaging; D008297:Male; D011446:Prospective Studies; D011654:Pulmonary Edema / Q000175:diagnosis*; D011655:Pulmonary Embolism / Q000175:diagnosis*; D011877:Radionuclide Imaging
chemical_list: D005338:Fibrin Fibrinogen Degradation Products; C036309:fibrin fragment D; D007770:L-Lactate Dehydrogenase; D001219:Aspartate Aminotransferases