Homocystinuria: a rare cause of megaloblastic anemia.

We present an eight-year-old boy who initially presented to us with megaloblastic anemia and subsequently developed dislocation of lens. The child had a positive sodium nitroprusside test and homocystinuria. He was diagnosed to have homocystinuria type 1. His anemia improved on oral pyridoxine and folic acid therapy. Homocystinuria should be remembered as a cause of megaloblastic anemia.