Concurrent Primary Hyperparathyroidism and Sarcoidosis in a Patient With Severe Hypercalcemia

Abstract

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.

Keywords: adult primary hyperparathyroidism; endocrinology; hypercalcemia; parathyroid gland adenoma; sarcoidosis.

Figure 1. Axial CT scan of the neck with contrast

Axial neck CT scan with intravenous contrast depicting a distinct 9 mm oval-shaped nodule (blue arrow) contiguous with the lower aspect of the right thyroid lobe. The nodule exhibits enhancement, albeit to a lesser extent than the thyroid lobe (green arrow). The observed location and enhancement pattern strongly suggest the presence of a parathyroid adenoma. CT: computed tomography

Figure 2. Coronal chest CT scan showing features consistent with sarcoidosis

Coronal chest CT scan illustrating characteristic features of sarcoidosis. Ground glass opacities are evident in both lungs (blue arrows), accompanied by micronodules along the peribronchovascular bundles (red arrow), and subpleural distribution of these micronodules along the fissure (green arrow). CT: computed tomography

Figure 3. Photomicrograph of bone marrow biopsy showing features consistent with sarcoidosis

Bone marrow histopathology (H&E, 20X) depicting numerous non-necrotizing epithelioid granulomas indicative of sarcoidosis (black arrows). H&E: hematoxylin and eosin

Figure 4. Histopathological specimen of the parathyroid adenoma

(A) Histopathological specimen illustrating a distinct proliferation/nodule with neighboring normal parathyroid tissue (arrow), characteristic of adenoma (H&E, 4X). (B) Adenoma cells exhibiting moderate to abundant eosinophilic slightly granular cytoplasm, indicative of oxyphilic variants (H&E, 40X). Chromogranin immunostaining confirmed positivity in adenoma cells (not depicted). H&E: hematoxylin and eosin