Concurrent Primary Hyperparathyroidism and Sarcoidosis in a Patient With Severe Hypercalcemia.

Hypercalcemia is a common biochemical abnormality caused by various etiologies, with primary hyperparathyroidism (PHPT) and malignancies being the most common culprits. Differentiating between PTH-dependent and PTH-independent hypercalcemia is crucial in clinical practice. However, in certain clinical contexts, it is important to consider the rare occurrence of two separate conditions causing hypercalcemia simultaneously. Herein, we have described the case of a patient who presented with high serum calcium, a normal PTH level, and histopathological evidence of active granulomatous disease, indicating the presence of both PHPT and sarcoidosis. The coexistence of these conditions poses diagnostic challenges due to their biochemical and clinical similarities. This case highlights the importance of individualized management for patients with concurrent conditions contributing to hypercalcemia. It also emphasizes the need for further research to unravel the underlying interactions between PHPT and sarcoidosis in the context of calcium metabolism. A better understanding of these interactions can guide optimal diagnostic and therapeutic strategies for patients with complex presentations of hypercalcemia.