Lithium therapy and hyperparathyroidism: an evidence-based assessment.
BACKGROUND
Prolonged therapeutic exposure to lithium compounds can have adverse consequences on calcium homeostasis. A unique form of hyperparathyroidism appears to be causally linked to chronic lithium exposure. We provide a comprehensive review of relevant literature using a structured, evidence-based approach.


METHODS
Published data were identified from systematic electronic literature searches. References are assigned a level of evidence according to a validated classification schema.


RESULTS
Level III and V evidence supports an etiologic link between sustained lithium therapy and both hypercalcemia and hyperparathormonemia (grade C recommendation). Level V evidence supports the use of preoperative parathyroid imaging if a focused exploration is planned (grade C recommendation). Level V evidence supports the use of intraoperative parathyroid hormone monitoring to guide appropriate surgical therapy (grade C recommendation). There is conflicting and equally weighted level V evidence supporting a routine preoperative plan of bilateral neck exploration versus selective unilateral exploration (no recommendation). There may be a role for calcimimetic drug therapy as an alternate, nonsurgical means of controlling lithium-associated hyperparathyroidism (grade C recommendation).


CONCLUSIONS
Evidence-based recommendations support screening of patients on chronic lithium therapy for hypercalcemia. Appropriate surgical therapy may consist of either a bilateral or a unilateral approach when performed by an experienced endocrine surgeon. Focused approaches should be guided by preoperative imaging and intraoperative hormone monitoring. Calcimimetic therapy is a potential alternative to parathyroidectomy.
Saunders
Brian D
BD
Department of Surgery, Pennsylvania State Milton S. Hershey Medical Center, Penn State University College of Medicine, Mail Code H070, 500 University Drive, PO Box 850, Hershey, PA 17033-0850, USA. bsaunders@hmc.psu.edu
Saunders
Erika F H
EF
Gauger
Paul G
PG
D006801:Humans; D006934:Hypercalcemia / Q000139:chemically induced; D006961:Hyperparathyroidism / Q000097:blood / Q000139:chemically induced* / Q000628:therapy; D018020:Lithium Compounds / Q000009:adverse effects* / Q000494:pharmacology; D010280:Parathyroid Glands / Q000187:drug effects; D010281:Parathyroid Hormone / Q000097:blood
D018020:Lithium Compounds; D010281:Parathyroid Hormone