hyperCA

Yesterday we discussed a case of hypercalcemia, likely secondary to malignancy.

We reviewed an approach to determining the aetiology of hypercalcemia, with first break point being PTH level.

If PTH appropriately low:
-Malignancy (PTHrP which is hard to order at LHSC without permission)- associated with squamous cell CA
-Mets to bone
-Myelomoa
-hyperVitamin D from lymphoma, or granulmaotous disease
-Medications (HCTZ, tums-->milk alkali )
-Endocrine causes (hyperthyroid, AI, pheo, acromegaly)- often NOT the way these conditions present
-Rhabdo

If PTH normal or HIGH:
-Primary/secondary/tertitatry hyper PTH (likely in outpatients)
-lithium
-familial hypercalcemic hypocalciuria

Malignancy can cause hypercalemia in 4 ways:
1. PTHP
2. Mets to bone
3. Vit D production
4. Rarely PTH production

 Malignancy associated hypercalcemia is summarized in THIS NEJM article.

The TREATMENT of elevated calcium:
FLUID!!! and lots of it
Lasix ONLY if volume overloaded
Consider bisphospinate if cancer but take time to work
Calcitonin is fast but there is tachiphalaxis.
Hyper V causes- consider steroids

HERE is a review looking at the use of lasix for treatment of hyperCA