Primary Hyperparathyroidism and Pulmonary Embolism in Patients With a Fractured Neck of Femur.

Two patients aged 82 and 77, with a fractured neck of the femur, were found to have primary hyperparathyroidism, characterized by hypercalcemia and hypercalciuria. Post-surgery, both developed pulmonary embolism (PE), highlighting a possible link between hypercalcemia and increased hypercoagulation risk. There have been few case reports suggesting the association between hypercalcemia due to hyperparathyroidism and the increase in tendency of hypercoagulation and subsequent risk of venous thromboembolism (VTE). This case series offers insights into how ionized calcium influences thrombin formation, platelet activation and aggregation, and activation of clotting factors such as factor VII and factor X, raising questions about the role of chronic hypercalcemia in VTE. Further research is needed to 1) establish whether chronic hypercalcemia in the absence of fracture can modulate the risk of hypercoagulation; 2) determine whether chronic hypercalcemia in individuals with bone fracture may represent a significantly higher hypercoagulability risk during the postoperative periods.