Bleeding in uraemia

Bleeding is relatively common in uraemic patients and arises from abnormal platelet function. Bleeding occurs roughly in proportion to the degree of renal insufficiency and may be severe. Most commonly, it is mucosal and gastrointestinal.

The mechanisms responsible are not fully understood but are thought to involve:

• increased prostacyclin production by the endothelium and reduced biosynthesis of thromboxane by platelets
• toxic effects of accumulated waste products (e.g. urea) resulting in impaired platelet coagulant activity, decreased platelet adhesion, and defects in cytoplasmic calcium mobilisation and platelet aggregation

Haemodialysis may be effective in reducing the bleeding tendency but rarely eliminates it. Additional measures include administration of cryoprecipitate, diamino - D - arginine vasopressin (DDAVP) and conjugated oestrogen. Patients who are also anaemic often benefit from blood transfusion or administration of recombinant erythropoietin.