Cerebral vascular complication and hyperhomocysteinemia in a cystinotic uremic child

We report a 13-year-old girl with nephropathic cystinosis on chronic perito neal dialysis who presented with two episodes of stroke. Laboratory evaluat ion showed severe hyperhomocysteinemia (108 mu mol/l). Further testing reve aled that she was homozygous for the thermolabile variant of the methylenet etrahydrofolate reductase (MTHFR) gene. Treatment with folic acid and vitam in B-12 lowered plasma homocysteine to less than 20 mu mol/l. No further ep isodes of stroke occurred over a follow-up of 12 months. Homocysteine level s should be measured in patients with chronic renal failure, since simple a nd safe treatment with folic acid and vitamin B-12 is effective in lowering the plasma homocysteine level in patients with the thermolabile MTHFR alle le.