Calcium Disorders

Question 1

Most common cause of hypercalcemia

Answer 1

Malignancy, due to osteoclast incrased activity from:

. incrs PTHrP
increased Vit D f
RANKL activation
or ectopic PTH secretion

Question 2

Causes of hypercalcemia

Answer 2

maligancy

primary hpth

Question 3

Calcitriol

Answer 3

1,25-DH D3

Question 4

Indication for surgery in primary hyperparathyroidism

Answer 4

age <50 years of age

osteoporosis or a fragility fracture
renal calculi
impaired renal function
hypercalciuria

Question 5

Medical management in hyperparathryoidism, primary

Answer 5

Cinacalcet

Question 6

Diagnosis of hypercalcemia

Answer 6

Serum Ca
Ionized ca (due to albumin variation)
PTH
Phosphorus, VIt D

Question 7

Acute tx of hypercalcemia

Answer 7

IV fluid at high rates (200-500cc/hr) with goal UOP of 2ml/kg/hr
Loop diurectics once hydrated
IV bisphosphonates (take days)
Denosumab
Calcitonin as bridge to bisphosphonates, careful of tachyphylaxis after a fe days

Last resort: dialysis

Question 8

Hypocalcemia causes

Answer 8

Low PTH:

Acquired hypoparathyroidism (surgery or autoimmune)

Hereditary hypoparathyroidism

Hypomagnesemia

Abnormal parathyroid gland development (DiGeorge syndrome)

High PTH:
Vitamin D deficiency (decreased intake or malabsorption)
Vitamin D–dependent rickets
Chronic kidney disease
Sepsis
Hyperphosphatemia (tumor lysis syndrome or acute kidney injury)

Question 9

Tx for hypocalcemia

Answer 9

> 7.5: Ca + Vit D supplement

<7.5 IV calcium, replenish mag