Gas6 evaluation in patients with acute dyspnea due to suspected pulmonary embolism.
BACKGROUND
Gas6 protein is involved in pulmonary embolism (PE) and acute inflammation in animal models.


METHODS
We enrolled 82 consecutive patients with acute dyspnea and suspected PE (Geneva score with high (HCP) or low/intermediate clinical probability (LICP)+D-dimer >or=0.5microg/mL) and 29 age-matched healthy volunteers. According to clinical and instrumental evaluations the following diagnoses were obtained: heart failure (HF), pulmonary or systemic infection (I), PE, or no illness (N). Twenty-two patients were excluded due to oral anticoagulation (9), lack of CT angiography or pulmonary scintigraphy (6), plasma creatinine >or=3mg/dL (3), and pulmonary cancer (4). Plasma Gas6 was measured with a validated enzyme-linked immunoassay. Non-parametric tests and accuracy measures were calculated.


RESULTS
Out of 60 patients included, 8 were N, 12 HF, 11 I and 29 PE. Gas6 median value in the N group (20.4ng/mL, interquartile range 17.6-21.6) matched that of healthy volunteers, 19.1 (17.2-21.4). Median Gas6 values in HF, 26.4 (21.6-33.3) and I groups, 34.1 (30.0-38.7), were significantly higher than those in PE 18.2 (16.3-23.3) or N (Kruskal-Wallis test p<or=0.05) groups. Gas6 test improved PE diagnosis with an area under the curve of 0.80 and 0.91 (in all and LICP patients). A 24ng/mL threshold excluded PE in 33% of LICP patients without loosing any diagnosis.


CONCLUSIONS
The data link Gas6 protein to infection/inflammation, but not to PE, in humans. Gas6 assay was useful in PE diagnosis, improving D-dimer accuracy particularly in LICP patients, and limiting false positives.
Sainaghi
Pier Paolo
PP
Internal Medicine, Department of Clinical and Experimental Medicine, University of Eastern Piedmont A. Avogadro, Novara, Italy.
Alciato
Federica
F
Carnieletto
Stefania
S
Castello
Luigi
L
Bergamasco
Luca
L
Sola
Daniele
D
Bongo
Angelo Sante
AS
Inglese
Eugenio
E
Polosa
Riccardo
R
Avanzi
Gian Carlo
GC
D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood; D016022:Case-Control Studies; D003404:Creatinine / Q000097:blood; D003937:Diagnosis, Differential; D004417:Dyspnea / Q000175:diagnosis* / Q000209:etiology; D004797:Enzyme-Linked Immunosorbent Assay; D005338:Fibrin Fibrinogen Degradation Products / Q000032:analysis; D006333:Heart Failure / Q000150:complications / Q000175:diagnosis*; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins / Q000097:blood*; D008875:Middle Aged; D055420:Perfusion Imaging; D011655:Pulmonary Embolism / Q000150:complications / Q000175:diagnosis*; D012141:Respiratory Tract Infections / Q000150:complications / Q000175:diagnosis*; D012680:Sensitivity and Specificity; D036542:Tomography, Spiral Computed / Q000379:methods; D000099255:Growth Arrest-Specific Protein 6
D015415:Biomarkers; D003404:Creatinine; D005338:Fibrin Fibrinogen Degradation Products; D036341:Intercellular Signaling Peptides and Proteins; D000099255:Growth Arrest-Specific Protein 6; C036309:fibrin fragment D