Validation of an Automated Immunoturbidimetric Assay for Fibrinogen/Fibrin Degradation Products Measurement and its Correlation to a Semi-Quantitative Latex Agglutination Test.
BACKGROUND
Laboratory determination of fibrinogen/fibrin degradation product (FDP) levels is important as a hyperfibrinolytic state marker. The aim of the study was to verify the analytical performance of an automated immunoturbidimetric assay (AIMT) for FDP and its comparison to a latex agglutination semiquantitative (SLAT) test.


METHODS
Total precision and accuracy was calculated following the EP 15-A2 protocol at two levels of controls. The protocol EP6 was performed for linearity. For semi-quantitative methods comparison, 71 consecutive samples were used. Concordance between methods results in term of positive and negative, and in categories, from <10 to > 160 µg/mL, was calculated through Cohen kappa coefficient ().


RESULTS
Total CV%: low control (10.8 µg/mL) 8.0 and 3.7 vs. 4.8 and high control (31.3 µg/mL) 2.7 and 3.8 vs. 3.6, for coagulometer ACL TOP 500 and 300 vs. manufacturer claimed, respectively. Linearity between 0 and 125 µg/mL showed polynomial fit analysis applicable. When correlating AIMT to SLAT, a good concordance was observed:  of results expressed as positive-negative = 79.5% with 90.1% of agreement (p < 0.001), of results expressed as categories = 72.2% (p < 0.001) with 80.3% concordance.


CONCLUSIONS
AIMT presented good analytical performance, and the concordance with SLAT by comparison of patients' samples results was also good. The implementation of IMMT in the clinical laboratory is suitable and reliable.
Marta E
ME
Martinuzzo
Cecilia
C
Ujhelly
Luis H
LH
Barrera
Maria A D
MA
Adamo
Marina S
MS
Lopez
Juan C
JC
Otaso
Jose
J
Oyhamburu
D057205:Automation, Laboratory; D015415:Biomarkers / Q000097:blood; D001777:Blood Coagulation; D001778:Blood Coagulation Disorders / Q000097:blood / Q000175:diagnosis*; D016022:Case-Control Studies; D004211:Disseminated Intravascular Coagulation / Q000097:blood / Q000175:diagnosis; D005338:Fibrin Fibrinogen Degradation Products / Q000032:analysis*; D006801:Humans; D000074024:Immunoturbidimetry; D007841:Latex Fixation Tests; D016014:Linear Models; D011237:Predictive Value of Tests; D015203:Reproducibility of Results
D015415:Biomarkers; D005338:Fibrin Fibrinogen Degradation Products