Haemolytic-uraemic syndrome: deficiency of plasma factor(s) regulating prostacyclin activity?

It is suggested that patients with the haemolytic-uraemic syndrome and related disorders (such as thrombotic thrombocytopenic purpura) lack a plasma factor which stimulates prostacyclin (P.G.I2) activity. Normal plasma would supply the missing factor and is a rational treatment for some life-threatening symptoms (thrombocytopenia, haemolytic anaemia, hypertension) of this syndrome.