Hypercalcemia (Assessment and Plan)

Author: William J Gibson MD, PhD

#Hypercalcemia

Corrected Ca = Serum Ca + 0.8 x (4-Alb)

Diagnostic approach:

Initial labs: Get serum PTH, ionized calcium, 1,25(OH)D, 25(OH)D.

High PTH: Primary hPTH, FHH (check 24H urine Ca/Cr ratio), tertiary hPTH

Low PTH:

PTHrP-driven: Malignancy (lung, breast, RCC)

High 1,25(OH)D: Granulomatous disease (TB, sarcoid), lymphoma

High 25(OH)D: Vit D toxicity

Normal labs: Multiple myeloma, milk-alkali, hypothyroidism, adrenal insufficiency, pheo, thiazides, lithium

Treatment:

– If mild: conservative tx, encourage PO, oral phos repletion

– IV fluids (NS bolus, drip), pts typically dehydrated

– Calcitonin 4-8U/kg SC BID for 48hrs

– Bisphosphonates (zoledronate preferred vs pamidronate except in MM), caution if CKD

– Consider Denosumab (anti-RANKL) if refractory to bisphos

– Primary hyperPTH: surg curative. If poor candidate, cinacalcet, bisphos, tamox.

– If life-threatening: HD