Content area
Full Text
Following successful parathyroidectomy, subjective improvement in recognized symptoms and in the overall "well being" of asymptomatic primary hyperparathyroid patients has been well documented. Because quantitative methods for measuring parathyroid hormone (PTH) and normal reference ranges of serum calcium have changed in recent years, a revised biochemical criteria for evaluating postoperative outcome has become necessary. Two hundred seventy-one selected patients were followed for an average of 6.3 years after parathyroidectomy. Although 257 patients had serum calcium levels <10.6 mg/dL during the entire follow-up period, 15 per cent of them had elevated intact PTH (iPTH) levels. Fourteen patients had calcium levels >:10.6 mg/dL at some point during follow-up, with nine patients (64%) showing high iPTH levels and eight (57%) of them developing recurrent hyperparathyroidism (calcium >11 mg/dL and WTH >68 pg/mL). Of the 14 remaining patients, 5 had hypercalcemia with normal iPTH levels. In patients with successfully treated primary hyperparathyroidism, the recommended annual follow-up is: 1) monitor total serum calcium only if serum calcium level is <10.6 mg/dL, or if serum calcium level is >10.6 mg/dL; and 2) monitor serum calcium and PTH levels, because these patients have an increased incidence of hyperfunctioning parathyroid glands, which may point to late recurrence.
IT HAS BEEN recognized for some time that successful parathyroidectomy is often followed by relief of symptomatic bone pain, a decrease in stone formation, and improved mental status in most patients with advanced primary hyperparathyroidism.' Clark et al.2 have also reported improvement in the overall "well being" of asymptomatic hyperparathyroid patients after parathyroidectomy with return to normocalcemia. However, long-term results of these subjective clinical findings have not been reported. Also, postoperative outcomes are often described in terms of nonspecific normocalcemia without reference to quantitative biochemical values.3 The exact definition of recurrence of hyperparathyroidism in reported series varies with respect to the normal calcium levels used, and often there is no mention of parathyroid gland secretion. Moreover, recently developed technologies have changed the normal laboratory reference ranges of serum calcium and parathyroid hormone (PTH). Before 1990, in our hospital group, the normal range for total serum calcium was 9 to 11 mg/dL. Since then, the normal range has dropped to 8.4 to 10.2 mg/dL. PTH determination has also changed significantly in the last 10 years. C-terminal...