title: Reference values for urinary calcium and phosphorus to prevent osteopenia of prematurity.
abstract: The prevention of osteopenia of prematurity is an important issue in the care of preterm infants. Fetal bone mineral accretion has been achieved in preterm infants by establishing and maintaining a simultaneous slight excretion of calcium (Ca) and phosphorus (P) (urine concentrations of 1-2 mmol/l) by means of an individual supplementation with Ca and/or P, resulting in a slight surplus supply (SSS). In this issue, Aladangady et al. present associations between urinary Ca/Cr and PO(4)/Cr ratios of preterm infants and biochemical variables of bone mineral metabolism. However, to date it has not been proven that these variables are a reliable substitute for direct measurement of bone mineral content (BMC). Before Ca/Cr and PO(4)/Cr ratios can be recommended as a new reference for improving BMC, the following steps are required: (1) direct measurement of BMC, (2) a prospective interventional trial to test and compare this new reference with the existing one (SSS, urinary Ca and P of 1-2 mmol/l) investigating BMC as primary outcome, and (3) adequate proof that Ca and P/Cr ratios are superior to simple urinary Ca and P concentrations.
authors.forename: F
authors.initials: F
authors.lastname: Pohlandt
authors.forename: W A
authors.initials: WA
authors.lastname: Mihatsch
mesh_terms: D001851:Bone Diseases, Metabolic / Q000517:prevention & control* / Q000652:urine; D002118:Calcium / Q000652:urine*; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature / Q000378:metabolism / Q000652:urine*; D007235:Infant, Premature, Diseases / Q000517:prevention & control* / Q000652:urine; D010758:Phosphorus / Q000652:urine*; D012016:Reference Values
chemical_list: D010758:Phosphorus; D002118:Calcium