J Clin Pathol Qual Control.  1998 Jun;20(1):169-176.

Measurement of PT and APTT using Coagrex-700 and ThromboCheck reagents

• Kim JW
• Lee WS
• Lee KS
• Park MK
• Shin SC
• Kim HS

Abstract

BACKGROUND: Prothrombin time (PT) and activated partial thromboplastin time (APTT) are widely used to detect congenital and acquired coagulation disorders and to monitor anticoagulant therapy. It has been established that both coagulometers and reagents affect the results of PT and APTT. We evaluated the performance of the Coagrex-700 (International Reagents Corporation, Japan) and the characteristics of ThromboCheck (International Reagents Corporation, Japan) reagents and the results were compared with those of another coagulometer, ACL 3000 (Instrumentation Laboratory, Milano, Italy) and different reagents, Thromborel S (Behring Marburg, Germany), Actin (Dade, Miami, USA).
METHODS
The precision of the Coagrex-700 and ThromboCheck reagents and the stability of ThromboCheck reagents were evaluated with Coagtrol I, II (International Reagents Corporation, Japan) and normal pooled plasma for 20 days. International normalized ration (INR) in warfarinized patients (n=40) are compared between the result of Coagrex-700 using ThromboCheck PT and that of ACL 3000 using Thromborel S. Sensitivities to various factor deficiencies (factor VII, VIII, IX and XI) and to heparin in vitro and in vivo were evaluated and compared with other coagulometer and reagent combinations.
RESULTS
Coefficients of variation (CV) of PT ranged from 1.08% to 1.24% and CV of APTT ranged from 0.96% to 1.68%. In stability study, ThromboCheck reagents showed good results. The comparison study of INR indicated good correlation (R=0.957). The test for sensitivity to factor deficiency and to heparin showed different results according to the different combination of coagulometer and reagents used.
CONCLUSIONS
Studies for precision, stability of reagents and correlation of INR showed good results. However, studies for sensitivity to factor deficiency and to heparin indicated that ACL 3000 using actin was more sensitive than other combinations of coagulometer and reagents.

MeSH Terms

Actins
Heparin
Humans
Indicators and Reagents*
International Normalized Ratio
Partial Thromboplastin Time
Plasma
Prothrombin Time
Warfarin
Actins
Heparin
Indicators and Reagents
Warfarin