Platelet Prostacyclin Receptor Defect

Kaliman et al. (1985) reported the case of a 10-year-old girl admitted to hospital because of severe intermittent claudication. Occlusion of the left popliteal artery was discovered. Laboratory investigations showed marked diminution in sensitivity of platelets to prostacyclin and a defect in platelet prostacyclin receptor (600022) was discovered. Because of reduction in the value of PGI2-receptor of the high affinity type in a brother and to some extent in both parents, the defect was thought to be hereditary. In 2 males, aged 35 and 38 years, presenting with myocardial infarction, Sinzinger et al. (1991) found abnormal conversion of exogenous 14C-arachidonic acid by platelets incubated in vitro. Neither of the patient's platelets showed evidence of a lipoxygenase pathway. Platelet thromboxane formation from exogenous and endogenous substrate was high, while the platelet aggregation responses were normal. A myeloproliferative syndrome was suggested by findings of bone marrow aspiration.