Screening for Hyperparathyroidism by Measurement of Calcium in Patients Undergoing Thyroid Surgery: A Prospective Study.

This study screened for asymptomatic primary hyperparathyroidism (PHPT) by measuring calcium (Ca) before thyroid surgery. The study was prospective. A total of 676 patients without a suspicion of PHPT were studied. PHPT was defined as elevated Ca (in 2 measurements) in the presence of PTH>25 pg/ml and in the absence of hypocalciuria. PHPT was diagnosed in 5 patients (0.74%), all of them women. One of the 5 patients with PHPT had no indication for parathyroidectomy (PTx) according to current guidelines. Parathyroid adenoma was easily identified during perioperative assessment of thyroid surgery in 3 patients. In the other 2 patients (0.3%), localization of the adenoma required specific exploration, which was only performed because of the preoperative diagnosis of PHPT. Normalization of Ca and PTH was achieved in all 5 patients. In conclusion, in patients without a clinical or ultrasonographic suspicion of PHPT, approximately 300 individuals should be screened before thyroid surgery to avoid one reoperation (PTx) due to PHPT, which does not seem to be cost-effective.