The following is a summary of “Primary hyperparathyroidism after radioactive iodine therapy: Is it a distinct clinical entity?,” published in the JANUARY 2023 issue of Surgery by Bobanga, et al.

A relatively uncommon cause of primary hyperparathyroidism (pHPT) is radioactive iodine (RAI) therapy.

To assess the prevalence and latency time for the development of RAI-associated pHPT and identify clinical differences in pHPT patients with or without prior RAI treatment, a multi-institutional retrospective review of patients with pHPT who underwent parathyroidectomy from 1990 to 2020 was conducted by researchers.

A total of 1,929 patients with sporadic pHPT had parathyroidectomy, 48 (2.5%) of whom had received prior RAI therapy, compared to 1,881 (97.5%) who had not. About 43 (90%) individuals received RAI therapy for thyrotoxicosis. Age was inversely connected with average latency of 24 years (3-59 years). Individuals who had had RAI in the past had decreased calcium and PTH levels at surgery (P< 0.0001). Age, symptoms, pathology, ectopic glands, and cure rate did not differ significantly.

RAI, which accounted for 2.5% of sporadic pHPT, was a potential causal factor. As the delay is inversely correlated with age, RAI-associated pHPT may represent a milder variation of random pHPT.

Reference: americanjournalofsurgery.com/article/S0002-9610(22)00490-1/fulltext