Intraoperative parathormone measurement in patients with multiple endocrine neoplasia type I syndrome and hyperparathyroidism

Total or subtotal parathyroidectomy is considered the treatment of choice f or multiple endocrine neoplasia type I (MEN-I)-associated primary hyperpara thyroidism (HPT). However, persistent or recurrent HPT is frequently observ ed. The development of a rapid two-site immunoradiometric assay (IRMA) meth od for measuring intact parathormone (PTH) has provided a valuable tool for recognizing possible surgical failures. Our experience includes 16 MEN-I p atients (10 Females. 6 males) of mean age 35.5 years operated on between 19 90 and 1996, Total parathyroidectomy (TPTX) with autotransplantation of par athyroid tissue was the standard treatment. Blood samples for PTH measureme nt were drawn at the induction of anesthesia (basal value). 10 and 20 minut es after the removal of each gland, and 60 minutes after TPTX. Rapid PTH me asurement, which required only 15 minutes of incubation at 37 degrees C, sh owed a highly significant correlation (p < 0.0001) with the standard method . Circulating PTH levels exhibited a stepwise decrease during TPTX, reachin g a mean value of 22.3% of the baseline 20 minutes after removal of the las t gland. Two patients showed a prompt decrease of PTH after removal of the single enlarged gland, featuring the kinetics observed in the adenomas. One of these two patients was successfully treated with more conservative surg ery. None of the patients showed persistence or recurrence of HPT. In our e xperience, intraoperative measurement of PTH seems to be a valuable adjunct in both the diagnosis of multiglandular involvement and the prediction of surgical treatment in patients with primary parathyroid hyperplasia.