Chromium status of full-term and preterm newborns.

In order to obtain reference values from normal babies, Cr status of full-term newborns has been studied. Plasma and urine values were (mean +/- SEM) 0.7 +/- 0.1 micrograms/L and 0.9 +/- 0.3 micrograms/L, respectively, for the first month of life (n = 19), and 0.6 +/- 0.1 micrograms/L and 0.8 +/- 0.2 micrograms/L for the second-to-third-month period (n = 31). Premature newborns (gestational age 28-36 wk) were compared to these control values; concentrations were 0.9 +/- 0.1 micrograms/L and 1.1 +/- 0.2 micrograms/L for the first month (n = 47), and 1.0 +/- 0.2 micrograms/L and 1.5 +/- 0.3 micrograms/L for the second to third months (n = 27). For the whole group, there was a positive correlation between plasma and urine concentrations (p = 0.0001); multiple regression analysis was performed between plasma levels and gestational age at birth (p = -0.002) and postnatal age (NS). Plasma levels of prematures and full terms were statistically different (p = 0.03) only for the second- to third-month period. It is suggested that these high Cr levels result from high dietary intakes and/or high absorption rates.