Homocystinuria masquerading as vitamin B12 deficiency.

BACKGROUND Homocystinuria is a rare metabolic disorder characterized by excess homocysteine in the urine. Vitamin B12 deficiency has diverse cutaneous, nervous and ophthalmic manifestations. OBJECTIVE To report a case of homocystinuria masquerading as vitamin B 12 deficiency. CASE We hereby are presenting an interesting case of a 4 year old boy who was being treated for Vitamin B 12 deficiency on the basis of history of delayed milestone, abdominal pain and hyperpigmentation of skin which was diagnosed as homocystinuria. CONCLUSION It is important to carry out ophthalmological examination in every case of megaloblastic anemia if associated with blurring of vision and mental retardation.