Modified recalcification time: a global coagulation screening test.

Abstract

Hypercoagulability with resultant thrombosis as a leading cause of death remains unproven due to the lack of a global screening coagulation test documenting antecedent hypercoagulability. To fill this need a modified recalcification time (MRT) test that incorporates the contribution of all the circulating cellular and chemical mediators, including the important but neglected tissue factor, to coagulation is described. Aliquots of blood are incubated with saline and with endotoxin, and the MRT is instrumentally determined. Values outside the normal ranges of 5.3 to 8.5 minutes (saline) and 4.5 to 7.5 minutes (endotoxin) in the coagulation spectrum of 0 to 10 minutes to infinity are abnormal. Shorter values are inversely related to the degree of hypercoagulability. To assess MRT in detecting hypercoagulability, MRT values in conditions with known thrombotic risk that were reported individually are presented by indicating the percentages of each in the abnormal ranges. The conditions, all with statistically significant hypercoagulability, included early breast cancer, diabetes, head, neck, and colon cancer, peripheral vascular disease, and pregnancy. Modified recalcification time meets the criteria of a global coagulation screening test because of: 1) age-related prevalence of asymptomatic cancer and thrombotic cardiovascular disease, 2) specificity and sensitivity, and 3) expected lower morbidity and mortality with early intervention.