title: Urinary methylmalonic acid levels in patients with acute ischemic stroke.
abstract: OBJECTIVE
  Vitamin B-12 and folate deficiency are common, especially in people aged 55 or over, and accompanied by elevated methylmalonic acid (MMA) and homocysteine concentrations. The aims of the study were to investigate the relationship between serum vitamin B-12, homocysteine, folate, erythrocyte folate and urinary MMA in patients with ischemic stroke, and to develop a simple screening HPLC method for the measurement of urinary MMA.
  
  
  METHODS
  Twenty-eight patients aged 55 years and over with ischemic stroke and 23 age- and sex- matched healthy controls were included in the study. Serum vitamin B-12 and folate were measured by immunoassay; serum total homocysteine and urinary MMA concentrations by HPLC.
  
  
  RESULTS
  There was no significant difference in vitamin B-12, folate and homocysteine concentrations between the patient and control groups. Urinary MMA concentrations and erythrocyte folate levels were significantly higher in patients than controls. There was a significantly negative correlation between vitamin B-12 and MMA.
  
  
  CONCLUSIONS
  Increased urinary MMA excretion is associated with ischemic stroke and it may more robustly reflect vitamin B-12 deficiency in patients with ischemic stroke. The method used in this study is eligible for routine urinary MMA measurements.
authors.affiliation: Department of Clinical Biochemistry, Ankara Training and Research Hospital, Ministry of Health, Cebeci, Ankara, Turkey.
authors.forename: Nuran
authors.initials: N
authors.lastname: Kara
authors.forename: Mehmet
authors.initials: M
authors.lastname: Senes
authors.forename: Ozlem
authors.initials: O
authors.lastname: Coskun
authors.forename: Levent
authors.initials: L
authors.lastname: Inan
authors.forename: Gulsevim
authors.initials: G
authors.lastname: Saydam
authors.forename: Dogan
authors.initials: D
authors.lastname: Yucel
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002545:Brain Ischemia / Q000652:urine*; D003404:Creatinine / Q000652:urine; D005260:Female; D005492:Folic Acid / Q000378:metabolism / Q000652:urine; D006710:Homocysteine / Q000378:metabolism; D006801:Humans; D008297:Male; D008764:Methylmalonic Acid / Q000652:urine*; D008875:Middle Aged; D020521:Stroke / Q000652:urine*; D014805:Vitamin B 12 / Q000652:urine
chemical_list: D006710:Homocysteine; D008764:Methylmalonic Acid; D005492:Folic Acid; D003404:Creatinine; D014805:Vitamin B 12