Table 1.

Clinical features of patients with inherited deficiencies of antithrombin, protein C, protein S and activated protein C resistance [4] (*All these features are less evident in patients with activated protein C resistance, who appear to be less severely affected clinically)

VENOUS THROMBOEMBOLISM (>90% OF CASES) DEEP VEIN THROMBOSIS OF LOWER LIMBS (common) PULMONARY EMBOLISM (common) SUPERFICIAL THROMBOPHLEBITIS MESENTERIC VEIN THROMBOSIS (rare, but characteristic)

CEREBRAL VEIN THROMBOSIS (rare, but characteristic)

FAMILY HISTORY OF THROMBOSIS *

FIRST THROMBOSIS USUALLY IN YOUNG AGE (< 40 YEARS) *

FREQUENT RECURRENCES *

NEONATAL PURPURA FULMINANS (homozygous protein C and protein S deficiency