Predictive value of a normal ipsilateral parathyroid gland for single-gland disease in primary hyperparathyroidism

When treating primary hyperparathyroidism (PHPT), surgeons use visual cues to guide decision-making and judge disease extent. We assessed assess whether visual identification of a normal-appearing ipsilateral parathyroid gland (IPG) during parathyroidectomy predicts single-gland disease in patients with PHPT.

We retrospectively analyzed patients undergoing parathyroidectomy for PHPT. Diagnostic performance of a normal IPG appearance was assessed, and logistic regression identified independent predictors of single-gland disease.

572 patients were included. Mean age was 59 ± 14 years; 80% were female, 67% White. 311 (54%) had a normal-appearing IPG: 255 (82%) had single-gland disease, 56 (18%) multigland disease. A normal IPG yielded sensitivity 75%, specificity 76%, PPV 82%, NPV 67% for predicting single-gland disease. On multivariable analysis, a normal IPG was the strongest independent predictor (OR 8.50, 95% CI 5.61-12.86; p < 0.001); higher preoperative calcium was also associated. Model AUC was 0.84.

A normal-appearing IPG is a strong, independent indicator of single-gland disease but not definitive: 18% of patients with a normal IPG harbored multigland pathology.