Endocrine Abstracts

JOINT3722

Introduction: Sarcoidosis is a multi-system granulomatous disorder that can present with hypercalcemia, renal impairment, and other systemic manifestations. Hypercalcemia in sarcoidosis results from the overproduction of 1,25-dihydroxyvitamin D by activated macrophages within the granulomas. Here we present a case series on three patients diagnosed with sarcoidosis over the past 10 years in our trust.

Case Presentations: Case 1:A 37-year-old male presented with weight loss, fatigue, nausea, polyuria. Initial investigations revealed hypercalcemia (4.06mmol/l) and acute kidney injury (AKI) with elevated creatinine (315µmol/l). Computer tomography (CT) imaging was suggestive of sarcoidosis, and an elevated ACE level (220 IU/l) supported the diagnosis. Biopsy of left inguinal lymph nodes confirmed non-necrotizing granulomas. The patient was treated with intravenous fluids, bisphosphonates, and prednisolone, leading to improvement in hypercalcemia (2.45mmol/l) and renal function (creatinine 105µmol/l). Case 2:A 38-year-old male with sarcoidosis presented with hypercalcemia (3.4mmol/l) and AKI while on long-term prednisolone. Whilst CT-imaging showed bilateral mediastinal and hilar lymphadenopathy consistent with sarcoidosis, biopsies of these did not show granulomatous changes. ACE levels (92.8 IU/l) were elevated, supporting the diagnosis of sarcoidosis, despite the lack of granuloma formation on biopsy. Treatment with intravenous fluids and pamidronate, followed by prednisolone therapy, resulted in clinical and biochemical improvement. Case 3:A 63-year-old female with a 19-year history of sarcoidosis presented with persistent hypercalcemia (3.46mmol/l), muscle weakness, and polyuria, despite ongoing steroid therapy. CT-imaging showed no active granulomatous disease or malignancy, and the patient’s complex medical history, including chronic kidney disease and atrial fibrillation, complicated the management. The patient’s recurrent hypercalcemia was managed with bisphosphonates, which showed slight improvement in calcium levels.

Discussion: Sarcoidosis remains an important differential for hypercalcaemia and all patients should receive full body CT-imaging to guide further investigations and management including site for tissue biopsy. Whilst corticosteroids remain the cornerstone of treatment for sarcoidosis, these cases highlight the role of adjunct therapy including bisphosphonates in the management of the hypercalcaemia. These were sufficient to resolve associated complications including impaired renal function secondary to nephrocalcinosis and interstitial nephritis.

Conclusion: This case series highlights the complexities in diagnosing and managing sarcoidosis-related hypercalcemia. Clinicians should maintain a high index of suspicion for sarcoidosis in patients presenting with unexplained hypercalcemia and renal dysfunction, particularly when other causes such as malignancy have been excluded. It also reinforces the importance of early recognition and a multidisciplinary approach involving nephrology, endocrinology, and respiratory medicine to optimize patient outcomes.