Severe hypercalcemia and acute renal failure: an unusual presentation of sarcoidosis

Although hypercalcemia is a known metabolic complication of sarcoidosis, it is rarely a presenting manifestation. Long-standing hypercalcemia and hypercalciuria can cause nephrocalcinosis and chronic renal failure. Acute renal failure, although described, is also a rare presentation of patients with sarcoidosis. We describe two patients with sarcoidosis, who presented with severe hypercalcemia and worsening renal function. Parathyroid hormone levels were appropriately suppressed. This led to an extensive search for the cause of hypercalcemia. Finally, after a lymph node biopsy in both cases, a diagnosis of sarcoidosis was established, hypercalcemia resolved, and renal function improved in both cases after administration of prednisone.