Our case displayed important features: (1) markedly elevated serum calcium of 3.50 mmol/L in the absence of overt systemic sarcoidosis, (2) decreased 24-hour urinary excretion of calcium, (3) normal serum ACE activity and minimally elevated 1,25(OH)2D, and (4) hypercalcemia unresponsive to corticosteroid therapy. Here, ACE is linked to hypercalcemia disease.