Biochemical changes and osteosclerosis after sulphamezathine therapy in idiopathic hypercalcaemia of infancy.

In communications to the British Paediatric Association in 1952, Lightwood and Payne described a group of 10 infants between the ages of 3 and 7 months presenting with anorexia, vomiting, failure to thrive, constipation and sometimes polyuria and polydipsia. They had hypercalcaemia, azotaemia and normal alkali reserves and in two of them radiographs showed nephrocalcinosis. There was no obvious cause for the hypercalcaemia, such as hyperparathyroidism or hypervitaminosis D, so they regarded it as a new syndrome. Fanconi and Girardet (1952) and Schlesinger, Butler and Black (1952) described two cases with hypercalcaemia and bone changes similar to those described in this communication. In the case described by Fanconi and Girardet hyperphosphataemia was present and the calcium-phosphorus product considerably raised. Creery (1953) described a case of hypercalcaemia in infancy and this child had osteosclerosis and at times a very high serum calcium-phosphorus product, though the period of observation was short. These and other observations have awakened interest in what may be a disease hitherto undescribed, with a group of clinical phenomena the pathogenesis of which is not yet clear. I have studied four infants with the same syndrome at the Royal Victoria Infirmary and the Babies Hospital in Newcastle. Three of them had urinary tract infections, which are very frequently but not invariably present in this illness, and were treated with sulphamezathine as well as other drugs in order to attempt to control the extremely resistant infections. The purpose of this paper is threefold: first, to describe the toxic effects of sulphamezathine in three of these children, with special reference to the bone changes in one case; secondly, to correlate these bone changes with changes in the serum calcium-phosphorus products; and thirdly, to emphasize the clinical picture, which may lead a practitioner to suspect the disease so that treatment with sulphamezathine can be avoided. The biochemical changes in the following three cases are given in Table 1.