APC-RESISTANCE, ANTITHROMBIN-III-DEFICIEN CY AND PROTEIN-C-DEFICIENCYOR S-DEFICIENCY

Assessment of Risk of Thrombosis in Pill Users:/sensitivity, specifici ty and predictive values of potential screening tests for the predicti on of thromboembolic complications in pill users were calculated for t he 6 million German pill users. In spite of high specificities, the pr edictive values of a positive family history, an antithrombin III-, pr otein C- or protein S-deficiency or resistance to activated protein C (APC) are low due to the very low absolute risk of thrombosis among pi ll users. More than half of the 840 yearly cases would pass the screen ing protocol undetected. A two-step screening protocol is suggested us ing the family history as selection criterium (reducing the need for l aboratory screening by 85%) for laboratory investigation of APC sensit ivity and antithrombin III-, protein C- and protein S-deficiency. Geno typing for factor V Leiden mutation is useful in cases with equivocal APC sensitivities or to confirm a homozygous genotype.