Bilateral central retinal artery occlusions in an infant with hyperhomocysteinemia.

A previously healthy 7-week-old boy developed bilateral central retinal artery occlusions in the presence of hyperhomocysteinemia and elevated serum methylmalonic acid and was found to have a transcobalamin receptor mutation. Retinal arterial occlusion is uncommon in young patients and typically prompts a systemic workup. In cases of atypical retinal arterial occlusion, hyperhomocysteinemia should be investigated.