Critical Care Medicine-Endocrine Disorders>>>>>Parathyroid and Calcium
Question 4#

A previously healthy 62-year-old female is admitted to the intensive care unit for airway watch after sustaining numerous rib fractures in a motor vehicle accident. On additional workup, she is noted to have mild hypercalcemia of 11.5 mg/dL (normal 8.9-10.1 mg/dL) and mildly elevated PTH of 124 pg/mL (normal 10-65 pg/mL). Review of her CT scans demonstrates mild-moderate osteoporosis and bilateral nephrocalcinosis.

Which of the following is the recommended management for this patient’s hyperparathyroidism?

A. Alendronate
B. Vitamin D supplementation
C. Cinacalcet
D. Parathyroidectomy

Correct Answer is D

Comment:

Correct Answer: D

This patient has primary hyperparathyroidism but was previously asymptomatic. Studies have shown that most asymptomatic patients do not have progression of the disease, evidenced by worsening hypercalcemia, hypercalciuria, bone disease, and/or nephrolithiasis. However, the Fourth International Workshop on Asymptomatic Primary Hyperparathyroidism guidelines suggest that patients who meet at least one of the following criteria are at an increased risk for developing endorgan effects of primary hyperparathyroidism and thus should have surgical intervention:

• Serum calcium concentration of 1.0 mg/dL or more above the upper limit of normal
• Bone density score less than −2.5
• Previous asymptomatic vertebral fracture
• eGFR <60 mL/min
• 24-hour urinary calcium > 400 mg/d
• Nephrolithiasis or nephrocalcinosis on imaging
• Age less than 50 years

This patient above meets criteria based on serum calcium and nephrocalcinosis. Thus, parathyroidectomy is indicated.

Calcimimetic agents such as cinacalcet are recommended for patients who meet the above criteria but are not surgical candidates. Cinacalcet activates the calcium-sensing receptor in the parathyroid gland and inhibits PTH secretion. Patients who do not meet the above criteria should be treated with bisphosphonates. Bisphosphonates are potent inhibitors of bone resorption and can improve low bone mass in patients with untreated primary hyperparathyroidism. 25-hydroxyvitamin D levels should also be checked and supplemented if low. 

Reference:

1. Bilezikian JP, Brandi ML, Eastell R, et al. Guidelines for the management of asymptomatic primary hyperparathyroidism: summary statement from the Fourth International Workshop. J Clin Endocrinol Metab. 2014;99:3561.