A diagnosis of hypoparathyroidisma requires eitherundetectable or inappropriately low levels of endogenous PTHb in the presence of hypocalcemia2,c
Lab tests can confirm hypoparathyroidism and rule out other conditions.2 Tests may include2,3:
- Serum total and ionized calcium levels
- Intact PTH
- BUN/creatinine or eGFR (estimated glomerular filtration rate)
- 25-hydroxyvitamin D (25-OH vitamin D)
- 24-hour urinary calcium
In hypoparathyroidism, concentrations of active vitamin D and bone turnover markers are typically in the low-normal to low range.2
Following neck surgery, chronic hypoparathyroidism is established only after 6 months.
By second- or third-generation immunoassay.
(Albumin-adjusted) confirmed on at least two occasions separated by at least 2 weeks.
A physical examination should include testing for Chvostek’s and Trousseau’s signs2,3
Tapping the patient's cheek over the path of the facial nerve causes twitching in the upper lip
Inflating a blood pressure cuff on the patient's upper arm to a level above the systolic blood pressure for 3 minutes causes a painful carpal spasm
Neuromuscular irritability is the most common sign of hypocalcemia. Presentation depends on the severity and duration of hypocalcemia, and some patients may be asymptomatic
References: 1. NATPARA [package insert]. Shire-NPS Pharmaceuticals, Inc. 2. Brandi ML, Bilezikian JP, Shock D, et al. Management of hypoparathyroidism: summary statement and guidelines [published online ahead of print March 4, 2016]. J Clin Endocrinol Metab. 2016;101(6):2273-2283. doi: 10.1210/jc.2015-3907. 3. Shoback D. Clinical Practice. Hypoparathyroidism. N Engl J Med. 2008;359(4):391-403.