Dextran and hydroxyethyl starch do not interfere with fibrinogen measurement if Clauss method with mechanical clot detection is used

Recently, Adam and colleagues [4] analyzed plasma diluted with different proportions of saline or hydroxyethyl starch (HES). Fibrinogen concentration was over-estimated if the clotting time was measured photo-optically in samples diluted with HES. But fibrinogen measurements in analyzers that used mechanical clot detection endpoints were accurate. Fenger-Eriksen and colleagues [5] assessed the accuracy of fibrinogen measurements in different analyzers and different methods in plasma diluted in different proportions with saline, HES, and albumin. The authors found that the photo-optical measurement overestimated fibrinogen concentration but that mechanical detection did not. Thromboelastometry seems to be a rapid and accurate estimation of the level and function of fibrinogen but is not available in most centers. However, most laboratories can easily measure fibrinogen by the Clauss method using mechanical detection. We recommend that the European guidelines specifying the use of thrombo-elastometry over the Clauss method be revised and qualified accordingly.HES: hydroxyethyl starch.The authors declare that they have no competing interests.