Rectal exam will often detect perirectal tumors, although some can be quite small so careful palpation is necessary. The magnitude of elevation of hypercalcemia, phosphous level and PTH level can all be used to differentiate between the causes of hypercalcemia. Additionally PTH can be measured and is increased in patients with primary hyperparathyroidism and renal failure. Treatment of hypercalcemia Treat the underlying cause if possible and hypercalcemia may regress without specific treatment. Diuretics such as furosemide also promote urinary loss of calcium regardless of the cause for hypercalcemia.
Thiazide diuretics promote calcium reabsortion and are therefore contraindicated.
Glucocorticoids cause calciuresis and decrease the intestinal absorption of calcium. Glucocorticoids will cause lysis of neoplastic lymphocytes and therefore should not be given until a diagnosis has been made. Mithramycin is an anti cancer agent that reduces calcium reabsorption from bone. Calcitonin is quite effective in rapidly lowering serum calcium. Diphosphonates inhibit osteoclastic bone reabsorption resulting in a reduction in serum calcium.