Lithium Associated Hyperparathyroidism: An Evidence Based Surgical Approach

Background: Long-term lithium use in psychiatric patients may lead to lithium associated hyperparathyroidism (LAH). Although anecdotal case reports have appeared, an evidence based algorithm for management of LAH is lacking. Methods: A comprehensive literature search was performed (1973-2010) using PubMed with keywords; “lithium” “hypercalcemia” “hyperparathyroidism” “sestamibi” “intra-operative parathyroid hormone (IOPTH) monitoring” “parathyroidectomy” and “medical management”. All English language publications addressing etiology and clinical management issues concerning LAH were critically analyzed. Results: Lithium associated hyperparathyroidism occurs in 4.3% - 6.3% of chronic lithium users compared to the general population which has an incidence of 0.5% - 1%. 194 cases of LAH have been reported which includes 10 patients (5%) treated medically and 170 patients (88%) who underwent parathyroidectomy. No details were available for 14 patients (7%). Among parathyroidectomy patients, 104 (59%) had adenomatous disease and 66 (39%) had multiglandular hyperplasia. Preoperative localization studies were utilized in only 22 patients (13%) and IOPTH monitoring was reported in only 3 studies (32 patients, 19%). Among surgical patients, bilateral neck exploration (BNE) was the most common approach performed in 162 patients (95%); focused neck exploration was utilized in only 8 patients (5%). Parathyroidectomy normalized LAH biochemical changes in nearly all patients (90% - 97%) in the early post-operative period, but recurrent hyperparathyroidism occurred in 8% - 42% of patients. Conclusion: LAH is an under appreciated and poorly understood endocrine disorder. LAH has a higher incidence of multiglandular disease and bilateral neck exploration is mandatory in majority for disease control. Nonsurgical approaches may be useful in select patients on short-term lithium therapy.