The Relationship between Primary Hyperparathyroidism and Thrombotic Events: Report of Three Cases and a Review of Potential Mechanisms.

We have described three uncommon cases of patients who presented with clinical thrombotic events (stroke, pulmonary embolism and deep venous thrombosis) during the course of a hypercalcemia-induced hypercoagulable state. After thorough investigation, the diagnosis of primary hyperparathyroidism - due to a parathyroid adenoma - was established in all cases. The association between hypercalcemia and venous or arterial thrombosis has been previously described; however, relevant data are still insufficient. The existing evidence in the field was reviewed and the interesting underlying pathophysiologic mechanisms were also discussed. Further studies are required to shed more light on the unusual, still intriguing relationship between calcium and thrombosis.