Hypophosphatemia as an Early Metabolic Bone Disease Marker in Extremely Low-Birth-Weight Infants After Prolonged Parenteral Nutrition Exposure.

Abstract

Early metabolic bone disease (MBD) detection is important in preterm infants to decrease long-term consequence. We aim to explore the early MBD biochemical marker in extremely low-birth-weight (ELBW) infants. Retrospective cohort study of 95 preterm infants born in a tertiary care-level neonatal intensive care unit between January 2015 and June 2018, with birth weight <1000g. Thirty-five infants were "nothing by mouth" for >14days and categorized as the high-risk group; the remaining 60 were categorized as the control group. Mineral intake in the first 14days and the trend of serum calcium (Ca), phosphorus (P), and alkaline phosphatase (ALP) levels were compared in both groups. The Ca and P supplementation in the first 2weeks of life were inadequate in both groups. Compared with the control group, significantly lower serum P (mg/dL) levels were noted in the high-risk group on weeks 2 (3.65 ± 1.2 vs 4.67 ± 1.45; P < .001), 4 (3.21 ± 0.95 vs 5.83 ± 1.18; P < .0001), and 6 (3.94 ± 1.1 vs 6.22± 0.78; P <.0001). There was no significant difference in the serum Ca level, and significantly higher ALP (U/L) levels were found up until 2months of life in the high-risk group (458.36 ± 189.02 vs 335.7 ± 111.51; P < .014). Hypophosphatemia developed as early as 2weeks old in high-risk preterm infants because of inadequate supplementation. Neither the serum Ca or ALP levels were affected. Thus, the routine monitoring of serum P level should be started 2weeks after birth for early MBD detection in extremely ELBW infants.