Ca & Mg Flashcards
hypercalcemia definition
Serum calcium > 10.2 mg/dL
hypercalcemia causes
CHIMPANZEES Calcium supplementation Hyperparathyroidism/Hypothyroidism Iatrogenic (eg, thiazides, parenteral nutrition)/Immobility (especially in the ICU setting) Milk-alkali syndrome Paget disease Adrenal insufficiency/Acromegaly Neoplasm Zollinger-Ellison syndrome (eg, MEN type 1) Excess vitamin A Excess vitamin D Sarcoidosis and other granulomatous disease
History/PE in hypercalcemia
Usually asymptomatic but can present with bones (osteopenia, fractures), stones (kidney stones), abdominal groans (anorexia,constipation), and psychiatric overtones (weakness, fatigue, irritability, altered mental status).
work up for hypercalcemia
Best initial test: total/ionized calcium, Alb, Ph, PTH + electrolytes, BUN, Cr, Mg, and Alk-p levels.
■ Also consider:
Parathyroid hormone–related peptide (PTHrP) if malignancy
serum protein electrophoresis for multiple myeloma,
vitamin D (total 25 Vit D and 1,25 vitamin D levels) if granulomatous disease
(eg, sarcoidosis), iatrogenic vitamin D intake, or TB suspected.
■ Other work-up: ECG may show prolonged QT interval
Treatment for hypercalcemia
■ If serum calcium > 14 mg/dL, treat urgently with isotonic IV fluids (+/− furosemide) and calcitonin; bisphosphonates (eg, zoledronic acid, pamidronate) should be considered as well.
High sodium intake (in isotonic fluids)
facilitates renal calcium excretion and prevents renal complications (stones).
■ Treat the underlying disorder including steroids for some of the granulomatous
diseases.
loop diuretic VS thiazide in Ca disorders?
Loop diuretics (furosemide) Lose
calcium. Thiazide diuretics ↑ Tubular
reabsorption of calcium.
hypocalcemia definition
Serum calcium < 8.5 mg/dL
HYPOCALCEMIA causes
Parathyroid-related: Hypoparathyroidism (postsurgical, idiopathic), 2°
hyperparathyroidism (chronic kidney disease [CKD]), and pseudohypoparathyroidism.
In infants, consider DiGeorge syndrome.
■ Malnutrition, vitamin D deficiency.
■ Other: hypomagnesemia, acute pancreatitis, and chelation from citrate
found in blood products.
HYPOCALCEMIA causes
Parathyroid-related:
Hypoparathyroidism (postsurgical, idiopathic)
2° hyperparathyroidism (chronic kidney disease [CKD]) pseudohypoparathyroidism.
In infants, consider DiGeorge syndrome.
■ Malnutrition, vitamin D deficiency.
■ Other: hypomagnesemia, acute pancreatitis
History/PE of hypocalcemia
abdominal muscle cramps, dyspnea, tetany, perioral and acral paresthesias, and convulsions.
■ Facial spasm elicited from tapping of the facial nerve (Chvostek sign) and
carpal spasm after arterial occlusion by a BP cuff (Trousseau sign)
Dx of hypocalcemia
Ionized Ca2+ and PTH
Tx of hypocalcemia
Treatment
■ Treat the underlying disorder.
■ In most cases, will need to administer oral calcium supplements; give oral
and IV calcium for severe symptoms or signs.
■ Ensure magnesium repletion
Tx of hypocalcemia
Treatment
■ Treat the underlying disorder.
■ In most cases, will need to administer oral calcium supplements; give oral
and IV calcium for severe symptoms or signs.
■ Ensure magnesium repletion
most common patient population with hypomagnesemia.
Alcoholics
falsely low serum Ca in ….
hypoalbuminemia
