COPPER DEFICIENCY AND HYPOCALCEMIC RICKETS IN A SMALL-FOR-DATE INFANT

ABSTRACT. A case of copper deficiency associated with hypocalcemia, radiological features of rickets and hyperparathyroidism is described in a small-for-date infant (gestational age 39 weeks, B.W. 1240 g). Neonatal serum copper (Cu) levels were found between 223 and 138 μmol/l. She was given daily 2 400 U of vitamin D₂ and a load dose of 80 000 IU at the age of 55 days. At the age of 79 days, X-rays of the legs and wrist showed spread, cupped and frayed metaphyses. Serum Ca was 1.35 mmol/1, P=0.99 mmol/1 with high alkaline phosphatases (A.P.) 590 II/ml. But plasma level of 25 hydroxycholecalciferol (25-OH-CC) was normal = 10.8 ng/ml. Serum Cu was low=3.14 μmol/l and serum immunoreactive parathormone (iPTH) level was elevated: 520 μlEq/ml (N±100). Administration of vitamin D₂ (15 mg) induced an immediate normalization of serum Ca, normal serum iPTH (68 μlEq/ml) in one month, normal X-rays in two months and normal A.P. in four months. Serum Cu and ceruloplasmin levels increased slowly without any supplementation to subnormal levels at the age of eight months (14.9 and 1.65 μmol/1. Serum Cu concentrations were found to be normal (16.0–33.7 μmol/1) in five children with hypocalcemic rickets. These results suggest a role of Cu deficiency in the occurrence of this transient vitamin D-resistant rickets.