[Cerebral vascular complication of hyperhomocysteinemia. Controlling thromboembolic complications with folates].

BACKGROUND

Young patients who experience cardiovascular events may have raised levels of homocysteine. There may be several causes for this hyperhomocysteinemia.

CASE REPORT: Cerebrovascular disease occurred in a 40-year-old female smoker with hyperhomocysteinemia. This patient subsequently had several episodes of thromboembolism involving the brain and lower limb arteries. Prothrombin concentration was difficult to control with antivitamin K anticoagulants. Investigations to identify a genetic cause of hyperhomocysteinemia revealed that she was homozygous for the C677T mutation on the methylenetetrahydrofolate reductase gene. There was no G1691A mutation of the factor V gene, a risk factor for familial thrombosis. Supplementation with folic acid successfully halted episodes of thromboembolism (follow-up 2 years) and prothrombin levels stabilized under treatment.

DISCUSSION: The C677T mutation, which is common in the general population (15.7%), cannot explain the effect of folate supplementation alone. Other mutations affecting homocysteine metabolism could have a potentializing effect on vascular events.