Background: Lithium is frequently used in the treatment of bipolar disease. Although lithium-associated hyperparathyroidism (LAH) is well documented, reports concerning its pathologic findings are sparse. Because of a high-reported incidence of multiglandular disease, focused exploration for LAH is controversial.
Methods: From 1995 to 2007, data from 1207 consecutive patients who underwent concise parathyroid exploration for sporadic primary hyperparathyroidism (PHP) directed by quick intraoperative parathyroid hormone monitoring (QPTH) were reviewed to identify patients with LAH. Anatomic findings were determined. All patients had >5 months of follow-up.
Results: The incidence of LAH was 16/1207 (1.3%). The rate of multiglandular disease was not higher in LAH: present in 25% (4/16) patients with LAH and 12.3% (146/1191) patients without LAH (p = 0.13 Fisher two-tailed test). Among 16 patients with LAH, 12 (75%) had a single adenoma. The use of QPTH allowed unilateral exploration in 8 of 12 patients with single adenoma. Parathyroid exploration resulted in durable biochemical cure for all 16 patients with LAH.
Conclusion: Multiglandular disease seems to be no more frequent in patients with LAH than in patients with primary hyperparathyroidism (PHP) without LAH. Patients with LAH can be safely and effectively managed with selective unilateral exploration directed by intraoperative PTH monitoring.