Parathyroid apoplexy manifesting as fever of unknown origin.

Objective: To describe a rare clinical presentation of necrosis of a parathyroid adenoma, manifesting as fever of unknown origin.

Methods: We present a case report, including detailed clinical and laboratory data, of a patient with previously undiagnosed primary hyperparathyroidism in whom necrosis of a parathyroid adenoma developed during a psychiatric admission for depression.

Results: A 40-year-old woman was admitted with severe depression. During her hospitalization, she was found to have osteitis fibrosa cystica, pathologic fractures of her left femur, and primary hyperparathyroidism. Shortly after her admission, spontaneous necrosis of her parathyroid adenoma developed, in association with high-grade fever, acute hypercalcemic crisis, neck pain, hypophonia, and shortness of breath. Findings on extensive evaluation of the fever remained unremarkable, with persistent high-grade temperatures that resolved postoperatively.

Conclusion: Spontaneous necrosis of a parathyroid adenoma is a rare but well-documented complication of primary hyperparathyroidism. Fever, a previously undocumented associated finding, might be a part of the clinical syndrome of this complication.