Evaluation of New Latex FDP Assay

Abstract

The Dade latex FDP (fibrin/fibrinogen degradation products) reagents, recently introduced to the market, were evaluated against the Thrombowellco latex FDP reagents and the tanned red cell hemagglutination inhibition immunoassay (TRCHII). The Dade reagents gave positive results in the 10-40 µg/mL range in four of 20 normal sera; none of these samples was positive (ie,⩾10 µg/mL) with Thrombowellco or TRCHII reagents.With 54 patient samples, almost 60% showed FDP titers in the range of 20-80 µg/mL with the Dade assay; only about 30% of the same samples were shown to be in that range with the other two methods. In separate experiments,the agitation time was prolonged from two to 2.5 minutes. Five of eight normal sera turned positive with the Dade method, while none did so with the other two methods. The results indicate an unusual sensitivity of the Dade product toward serum FDP.