Serum calcitonin concentrations in premature infants during the first 12 weeks of life

Abstract

Twenty-eight premature infants of mean gestation 30.9±2.5 weeks and mean birth weight 1175±206 g had repeated serum calcitonin concentrations determined over the first 12 weeks of life. Serum calcitonin concentrations slowly fell but remained elevated even at 12 weeks of age [normal adult=71±48, 1 week (N=15)=327±167, 3 week (N=23)=270±129, 6 week (N=16)=249±154, 9 week (N=13)=214±108, 12 week (N=12)=174±11]. Throughout this period, serum total calcium was normal or low (8.4±.8–9.3±1.0). Serum phosphorus was normal or low (6.0±1.4–6.5±1.0), and serum magnesium was normal (1.7±0.24–1.8±0.34). The reason for the sustained elevation of serum calcitonin in these very small, sick, premature infants in unclear.