[Monitoring of plasma concentration of low molecular weight heparin--comparative evaluation with chromogenic and clotting assays].
The efficacy of low molecular weight heparin (LMWH) in the treatment of thrombosis is increasing interest in its clinical potential. However, the measurement of in vitro anticoagulant activities of LMWH has been controversial for its appropriate clinical dose. The study has been carried out to compare two methods for measurement of anti-factor Xa activity of LMWH (fragmin). One is 'HEPTEST' recently developed as a new clotting assay method and the other is an authentic chromogenic assay using S-2222. The coefficients of variation in intra-assay were 1.87-2.75% in clotting assay, and 0.61-0.89% in chromogenic assay. The sensitivity to detect minimum concentration was 0.02 IU/ml in clotting assay, and 0.04 IU/ml in chromogenic assay. The correlation between two methods was good (r = 0.935), whereas clotting assay has been revealed as a very simple rapid method. LMWH (fragmin) with 75 IU/kg/day was administered to three patients with coagulopathy; two disseminated intravascular coagulopathy (DIC) and one veno-occlusive disease (VOD). Hemostatic abnormalities have been improved serially after treatment in all patients. During treatment, the plasma concentration of LMWH was measured, showing 0.05-0.23 IU/ml in DIC and 0.02-0.10 IU/ml in VOD. These results suggest that measurement of plasma concentration of LMWH using the easy and rapid clotting assay method as 'HEPTEST' is clinically useful for monitoring to detect clinical dose of LMWH for DIC and thrombosis.
Katagiri
H
H
Department of Laboratory Medicine, Keio University, School of Medicine, Tokyo.
Itoh
S
S
Uchida
T
T
Kawai
Y
Y
Watanabe
K
K
D000925:Anticoagulants / Q000097:blood*; D001780:Blood Coagulation Tests; D002863:Chromogenic Compounds; D004211:Disseminated Intravascular Coagulation / Q000188:drug therapy; D016903:Drug Monitoring / Q000379:methods*; D006495:Heparin, Low-Molecular-Weight / Q000097:blood* / Q000627:therapeutic use; D006801:Humans; D012680:Sensitivity and Specificity; D014652:Vascular Diseases / Q000188:drug therapy
D000925:Anticoagulants; D002863:Chromogenic Compounds; D006495:Heparin, Low-Molecular-Weight