We measured urinary cyclic AMP (UcAMP) excretion after parathyroidectomy in order to assess postoperative parathyroid function. Patients undergoing successful treatment for primary hyperparathyroidism were divided into three groups based on therapy required to correct postoperative hypocalcaemia: 1 (n= 44) vitamin D not required; 2 (n= 17) vitamin D required temporarily (< 1 year); 3 (n= 10) vitamin D required permanently (> 1 year). Patients in group 1 experienced only brief (< 7 days) hypocalcaemia. UcAMP fell immediately postoperatively and returned to the normal range (in the majority) within 7 days. Group 2 showed the most severe hyperparathyroidism as judged by preoperative serum calcium, alkaline phosphatase and UcAMP and eight of seventeen showed radiographic evidence of osteitis fibrosa cystica (OFC). Patients in this group developed severe hypocalcaemia postoperatively, but in the majority UcAMP was elevated in proportion to the degree of hypocalcaemia and could be suppressed by raising serum calcium. Hypocalcaemia in these patients was presumably due to calcium entry into bone associated with healing of skeletal disease. Group 3 patients also developed severe postoperative hypocalcaemia but showed significantly lower UcAMP excretion than groups 1 or 2. We conclude that measurement of UcAMP excretion is helpful in the diagnosis and management of postparathyroidectomy hypocalcaemia. The combination of low UcAMP and hypocalcaemia more than 7 days after parathyroidectomy indicates hypoparathyroidism that will usually but not always require permanent therapy with vitamin D. Postoperative hypocalcaemia accompanied by increased UcAMP indicates that parathyroid gland function persists and that lifelong treatment with vitamin D will generally not be required.
|Original language||English (US)|
|Number of pages||9|
|Publication status||Published - Jul 1981|
ASJC Scopus subject areas
- Endocrinology, Diabetes and Metabolism