Guide to Hypercalcemia

Causes

  • Primary hyperparathyroidism (main outpatient cause)
  • Malignancy: PTHrP, osteolytic, calcitriol (main inpatient cause)
  • Granulomatous diseases
  • Drugs: milk-alkali, vitamin D, thiazides, lithium
  • Endocrine: hyperthyroidism, adrenal insufficiency
  • Paget’s Disease
  • Immobilization
  • Familial hypocalciuric hypercalcemia
  • ESRD and tertiary hyperparathyroidism

Clinical Manifestations:

  • GI: constipation, PUD, pancreatitis
  • Renal: stones, DI, RTA (type I), tubular toxicity (nephrocalcinosis)
  • Cardiovascular: QT short, HTN
  • Neurologic: Myalgias, weakness, confusion, coma

Helpful Hints:

  • Level: higher with malignancy, rarely >11 or 12 with primary hyperparathyroidism
  • Serum PO4: low with humeral hypercalcemia of malignancy (PTHrP) or hyperparathyroidism
  • Urine calcium:
    • High or high normal with hyperparathyroidism and malignancy
    • Low with milk alkali (due to metabolic alkalosis), thiazides, and FHH
  • Serum Cl: high in hyperparathyroidism

Workup:

Hypercalcemia

Management:

  • Normal saline: 2 to 4 L IV daily for 1 to 3 days. Enhances filtration and excretion of calcium. Lowers calcium by 1 to 3 mg per dL. Caution in HF patients.
  • Furosemide: Inhibits calcium resorption in the distal renal tubule. Use following aggressive rehydration. Watch for hypokalemia and volume depletion.
  • Bisphosphonates: Pamidronate (Aredia) 60 to 90 mg IV over 4 hours or Zoledronic acid (Zometa), 4 mg IV over 15 minutes. Inhibits osteoclast action and bone resorption; maximal effect at 72 hours. Often used for hypercalcemia of malignancy. Watch for nephrotoxicity, rebound hypercalcemia in hyperparathyroidism, and hypophosphatemia.
  • Calcitonin: 4 to 8 IU per kg IM or SQ every 6 hours for 24 hours. Inhibits bone resorption and augments calcium excretion. Initial treatment (after rehydration) in severe hypercalcemia. Watch for rebound hypercalcemia, vomiting, cramps, flushing, etc.
  • Steroids: Hydrocortisone, 200 mg IV total daily dose for 3 days. Inhibits vitamin D conversion to calcitriol. Useful in vitamin D intoxication, hematologic malignancies, granulomatous disease.

Am Fam Physician. 2003 May 1;67(9):1959-1966.

Nature Clinical Practice Nephrology (2007) 3, 397-404

Happy New Year – Top Innovations for 2015

Happy new year to all the housestaff, faculty, fellows, and anyone else out there who reads this blog ;). To start the year off right, here are the Top 10 Medical Innovations that will have an impact in 2015, determined by the Cleveland Clinic Medical Innovation Summit. Some of these innovations are driven directly by work done at UT Southwestern! Below, some points on the list have been highlighted – click the link to see the whole list and all of the exciting information about each innovation.

1. Mobile Stroke Treatment Unit: Each year in the United States, nearly 800,000 people suffer a stroke. 90% are thought to be ischemic, while 10% are hemorrhagic in origin. With the idea that “time lost is brain lost,” the mobile stroke unit hopes to decrease the time required for diagnosis and intervention. The ambulances will carry a special portable CT scanner – images can be taken in two minutes and sent over 4G wireless to neurologists and neuroradiologists to yield a diagnosis.

4. PCSK9 Inhibitors for Cholesterol Reduction:Through research driven by Helen Hobbs and Jonathan Cohen here at UTSW, PCSK9 inhibitors are described as “an ‘iconic example’ of translational medicine in the genomics era. Preliminary clinical trials have already shown that drugs that inhibit the PCSK9 protein — used with or without statins — produce dramatic reductions in LDL cholesterol (more than 70% in some patients).” There are now several PCSK9 drugs currently in various stages of development. In 2015, the Food and Drug Administration is expected to approve the first of these drugs for its ability to significantly lower LDL cholesterol and help patients achieve their treatment goals.

10. Angiotensin-Receptor Neprilysin Inhibitor for Heart Failure: UTSW scientist Dr. Milton Packer discussed the use of LCZ 696, a novel neprilysin inhibitor that, when combined with angiotensin receptor blockers, had a mortality benefit in patients with heart failure. The medication reduced cardiovascular death rates or hospitalization due to heart failure by 20 percent compared to standard treatment with the ACE inhibitor enalapril. It also reduced the risk of death due to any cause 16 percent compared with the group taking enalapril. Granted Fast Track status by the Food and Drug Administration, the heart drug is expected to be available in 2015 in the United States.