Summary
Since most patients with thrombophilia in Israel are referred for diagnosis to our
center, it was possible to estimate the relative frequency of the hereditary disorders
leading to thrombophilia. 107 unrelated patients were evaluated over 4 years. Diagnoses
were established in 23 patients (21.5%) while in 84 (78.5%) no abnormality was detected.
Antithrombin III deficiency was found in 8 patients (7.5%), dominant protein C deficiency
in 6 (5.6%), recessive homozygous protein C deficiency in 1, protein S deficiency
in 3 (2.8%) and dysfibrinogenemia in 1. Four additional patients (3.7%) had a lupus
anticoagulant. The frequency of deep vein thrombosis and pulmonary embolism was similar
in patients with and without a definite diagnosis. Thrombosis of visceral or cerebral
vessels and a positive family history were more frequent among patients in whom a
definite diagnosis was made. In both groups there was a substantial lag between the
time of presentation of the first thrombotic episode and the time of evaluation. Since
the number of referred patients with thrombophilia has gradually increased over the
period of the study, it is at present impossible to establish the prevalence of the
various hereditary disorders leading to thrombophilia in the population.
Key words
Thrombophilia - Antithrombin III - Protein C - Protein S - Lupus anticoagulant