A LABORATORY APPROACH TO THE EVALUATION OF HEREDITARY HYPERCOAGULABILITY

The concept of hypercoagulability and especially its evaluation in the clinical laboratory has changed dramatically during the last few year s. The genetic basis and the mechanisms of the various factors respons ible for hypercoagulability are briefly reviewed with emphasis on the most common genetic deficiencies. The major thrust of this review cent ers on the cost-effective approach to examining patients with a person al or family history of venous thrombosis. Several new concepts dealin g with thrombotic risk are presented with a focus on the theory that m ultiple factors cause thrombosis in affected patients. A proposal for a cost-effective sequential testing scheme for the accurate diagnosis of hereditary hypercoagulability is discussed. The knowledge of thromb otic risk factors is evolving rapidly, requiring the clinical laborato ry to remain flexible. Ultimately the clinical laboratory must take a leading role in the diagnosis of hereditary thrombotic disease by serv ing as the consultant to the primary caregiver by providing an up-to-d ate and cost-effective evaluation.