Axial osteomalacia.

total calcium with overt bone disease is hard to explain. The history of constipation, nocturia and polyuria, albeit mild, do suggest hypercalcaemia and it may be that the ionized calcium was elevated without the total calcium being raised. There are many points of similarity in the patient reported here with the case reported by Mather in 1953. His patient was a 39-year-old woman who had developed diffuse aching pains in the lower limbs and back 6 months before admission to hospital. His patient was shown to have evidence of osteitis fibrosa both by skeletal X-ray survey and sternal bone biopsy. Four values for the serum calcium concentration during the 3 months prior to the removal of a Wasserhelle cell parathyroid adenoma were all within the normal range. Studies of intestinal function were not, however, reported. Mather's patient is of considerable interest, not only because of the short duration of symptoms but also because, as far as we are aware, it is the only other reported case that was persistently normocalcaemic until the time of operation. The importance of the detection of cases of normocalcaemic primary hyperparathyroidism is stressed by the report of Nichols & Flanagan (1967). They reported six patients, with this syndrome, which represented 37% of all the patients in whom they had made a diagnosis of parathyroid hyperfunction in a 3-year period. Similarly the occurrence of eleven cases with this syndrome seen in one centre (George et al., 1965; Wills et al., 1969) over a 9-year period suggests a high incidence among patients with recurrent renal calculi. The patient reported here, together with that of Mather (1953), suggest that normocalcaemia in primary hyperparathyroidism may also be present in some patients with osteitis fibrosa.