Evaluation and Diagnosis

Hypoparathyroidism (HPT) evaluation and diagnosis

Clinical evaluation consists of patient history,
physical examination, lab tests, and imaging.

Watch: Diagnosis and
Evaluation of
Hypoparathyroidism
Doctor checking vitals | Learn how to diagnose Hypoparathyroidism.

Patient history

Patient history should include a review for1,2:

  • Thyroidectomy and/or parathyroidectomy.
  • Surgery to other structures of the neck.
  • Relevant family history of hypocalcemia or associated genetic disorders.

Physical exam

Assess for neuromuscular symptoms such as2:

Person Icon representing one of the neuromuscular symptoms of Hypoparathyroidism.

Fatigue

Chains Icon pointing at one of the neuromuscular symptoms of Hypoparathyroidism.

Generalized
muscle weakness

Elbow hurting Icon showing the placement of one of the neuromuscular symptoms of Hypoparathyroidism.

Muscle cramping,
which may be painful

Lungs icon showing bronchospasm and wheezing are some of the neuromuscular symptoms of Hypoparathyroidism.

Bronchospasm
and wheezing

Neuromuscular irritability may be observed by testing for both (A) Chvostek’s and (B) Trousseau’s signs.1

Doctor touching a man's face checking for Chvostek signs. Blood pressure test checking for signs of Trousseau.

Neurologic signs of HPT may include paresthesia and numbness—especially around the mouth, fingers, or toes—and seizures or spells.2

An electrocardiogram may reveal prolongation of the QT interval caused by HPT-induced hypocalcemia.3

Labs

Lab tests include1:

  • Serum total and ionized calcium
  • Parathyroid hormone concentration
  • Phosphate
  • Magnesium
  • BUN/creatinine
  • 25-hydroxyvitamin D [25(OH) vitamin D]

Once a diagnosis is made, initial evaluation should include a 24-hour urinary calcium excretion, estimated or calculated GFR, and a biochemical stone risk profile if clinically warranted.1

Diagnosing hypoparathyroidism

HPT diagnosis is established by concurrent measurement of1:

  • Albumin-corrected or ionized serum calcium below the lower limits of the normal range.
  • Low or undetectable levels of parathyroid hormone (PTH) on at least 2 occasions.

as determined either by a 2nd- or 3rd-generation immunoassay separated by at least 2 weeks.1

Conventional management of HPT may involve dietary and oral calcium, active vitamin D, magnesium, thiazide diuretics, phosphate binders, and/or other dietary changes.1

MANAGEMENT GUIDELINES

Evaluating for adequate control in HPT patients on conventional therapy requires monitoring not only of serum calcium, but also of serum phosphate, calcium-phosphate product, and urinary calcium. Symptoms, quality of life, and comorbidities must also be observed.1

Going beyond calcium

eGFR, estimated glomerular filtration rate

REFERENCES:

1. Brandi ML, Bilezikian JP, Shoback D, et al. Management of hypoparathyroidism: summary statement and guidelines. J Clin Endocrinol Metab. 2016;101(6):2273-2283. 2. Shoback DM, Bilezikian JP, Costa AG, et al. Presentation of hypoparathyroidism: etiologies and clinical features. J Clin Endocrinol Metab. 2016;101(6):2300-2312. 3. Monis EL, Mannstadt M. Hypoparathyroidism—disease update and emerging treatments. Ann Endocrinol (Paris). 2015;76(2):84-88. 4. Khan AA, Koch CA, Van Uum S, et al. Standards of care for hypoparathyroidism in adults: a Canadian and international consensus. Eur J Endocrinol. 2019;180(3):P1-P22.