Serum Calcitonin and Blood Mineral Interrelationships in Normal Children Aged Six to Twelve Years

Abstract

Summary: Simultaneous measurements of serum immunoreactive thyrocalcitonin (iTCT), immunoreactive parathyroid hormone (iPTH), calcium, inorganic phosphate, magnesium, and alkaline phosphatase were made in 37 normal children whose ages ranged from 6–12 years. Between the ages of 6 and 12 there is a statistically significant rise in serum iTCT levels (r = 0.4638; P < 0.01), and a fall in serum iPTH levels (r = 0.4976; P < 0.01). There is a highly significant inverse correlation between serum iTCT and iPTH levels (r = 0.5248; P < 0.005). Serum iTCT levels were inversely correlated with phosphate levels (r = 0.4989; P < 0.01), the latter being age dependent and falling significantly between the ages of 6 and 12 (r = 0.4802; P < 0.001). There was no significant relationship between serum calcium levels and iTCT, iPTH, or age. Serum magnesium levels were not correlated with calcium, iTCT, or iPTH levels. Speculation: Serum iTCT is important in the growth process, particularly in the steady growth towards the end of childhood. and the inverse relationship between iTCT and iPTH levels suggests that a dual control mechanism exists which is capable of striking the fine balance between bone anabolkm and catabolism necessary for normal skeletal growth.