Normocalcemic hyperparathyroidism: preoperatively a disease, postoperatively cured?

BackgroundUp to 44% of primary hyperparathyroidism patients have elevated parathyroid hormone (ePTH) with normal calcium postparathyroidectomy (PTx). The question is whether the surgical approach affects the incidence of this phenomenon.MethodsPatients with hyperparathyroidism and presumed single-gland disease on preoperative imaging who underwent PTx between 1994 and 2008 were identified and contacted for long-term follow-up. PTx was either a focused approach (minimally invasive approach [MIP]) or a bilateral neck exploration (BNE).ResultsIn total, 171 patients had PTH measured postoperatively (95 MIP and 76 BNE); 30 of 171 (17%) had ePTH with normal calcium (MIP 21 [22%] and BNE 9 [12%], P = .08). This occurred within 2 years in 48% and 67% and after 2 years in 52% and 33%, MIP vs BNE, respectively. Four patients recurred, 2 MIP and 2 BNE.ConclusionsThere is a trend toward a higher incidence of ePTH in patients having undergone an MIP. The etiology of ePTH is multifactorial but may represent an early recurrence.