title: Homocystinuria masquerading as vitamin B12 deficiency.
abstract: 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.
  
  
  METHODS
  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.
  
  
  CONCLUSIONS
  It is important to carry out ophthalmological examination in every case of megaloblastic anemia if associated with blurring of vision and mental retardation.
authors.affiliation: Dr RP Center for Ophthalmic Science, AIIMS, New Delhi, India.
authors.forename: M
authors.initials: M
authors.lastname: Wadhwani
authors.forename: S
authors.initials: S
authors.lastname: Beri
authors.forename: A
authors.initials: A
authors.lastname: Saili
authors.forename: S
authors.initials: S
authors.lastname: Garg
mesh_terms: D002675:Child, Preschool; D003937:Diagnosis, Differential; D006710:Homocysteine / Q000097:blood / Q000652:urine; D006712:Homocystinuria / Q000150:complications / Q000175:diagnosis* / Q000378:metabolism; D006801:Humans; D008607:Intellectual Disability / Q000209:etiology; D007906:Lens Subluxation / Q000175:diagnosis / Q000209:etiology*; D008297:Male; D014806:Vitamin B 12 Deficiency / Q000175:diagnosis
chemical_list: D006710:Homocysteine