title: Urinary methylmalonic acid excretion in infants fed formula or human milk.
abstract: Serum vitamin B-12 and urinary methylmalonic acid (MMA) concentrations were determined in 62 healthy infants aged 1-6 mo. Urinary MMA was inversely correlated with serum vitamin B-12 concentrations (r = -0.550, p less than 0.001); serum vitamin B-12 was higher (p less than 0.001) and urinary MMA concentrations were lower (p less than 0.001) in formula-fed infants than in infants fed human milk (from the breast). Human-milk-fed infants who had received supplemental formula had higher serum vitamin B-12 concentrations than did infants exclusively fed human milk. It is not clear whether the serum vitamin B-12 and urinary MMA concentrations in infants fed human milk reflect biochemical deficiency of vitamin B-12, and the clinical significance of these findings needs to be investigated.
authors.affiliation: Department of Pediatrics, University of Cincinnati Medical Center, OH 45267-0541.
authors.forename: B L
authors.initials: BL
authors.lastname: Specker
authors.forename: W
authors.initials: W
authors.lastname: Brazerol
authors.forename: M L
authors.initials: ML
authors.lastname: Ho
authors.forename: E J
authors.initials: EJ
authors.lastname: Norman
mesh_terms: D005260:Female; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D007223:Infant; D007225:Infant Food; D008297:Male; D008314:Malonates / Q000652:urine*; D008764:Methylmalonic Acid / Q000652:urine*; D008895:Milk, Human; D011863:Radioimmunoassay; D014805:Vitamin B 12 / Q000097:blood
chemical_list: D008314:Malonates; D008764:Methylmalonic Acid; D014805:Vitamin B 12