MANAGING HYPOPARATHYROIDISM
Guidelines and
strategies for managing hypoparathyroidism
Watch: Clinical Guidelines for theManagement of Hypoparathyroidism
Therapeutic objectives
International and European guidelines recommend the following therapeutic goals to prevent complications of hypoparathyroidism (HPT)1-3:
Prevent signs and symptoms of hypocalcemia. Maintain serum calcium level slightly below the normal range (no more than 0.5 mg/dL below normal) or in the low normal range.
Potential complications: Tetany, seizures, muscle cramps, paresthesia, other neuromuscular complications, fatigue, poor concentration, memory and cognitive function, impaired quality of life, and congestive heart failure (if severe and chronic).
Maintain calcium phosphate product <55 mg2/dL2.
Potential complications: Ectopic calcifications in the brain, kidney, vascular system, and soft tissues.
Avoid hypercalciuria.
Potential complications: Kidney stones, nephrocalcinosis, renal dysfunction, and end-stage renal disease.
Avoid hypercalcemia.
Potential complications: Symptomatic hypercalcemia (weakness, altered mental status, nausea, and abdominal pain) and increased risk of renal calcification.
Decrease potential for renal and other extraskeletal calcifications.
Potential complications: Renal dysfunction and progression to dialysis or transplantation. Central nervous system calcifications and possible dysfunction (eg, seizures, altered mental activity, and movement disorder), and vision loss.
Key monitoring parameters
Assessing for adequate control of HPT requires monitoring of laboratory values beyond serum calcium and observing their trends over time.
Assess every 3-6 months2,3,*
| Assessments3 | Target Range3-5 |
|---|---|
| Serum calcium | 8.0-9.0 mg/dL |
| Serum phosphate | 2.5-4.5 mg/dL |
| Calcium phosphate product | <55 mg2/dL2 |
| BUN/creatinine or eGFR | 90-120 mL/min/1.73 m2 |
| Magnesium | 1.7-2.6 mg/dL |
*Adjust frequency to:
|
|
Assess at least once per year3,†
| Assessments3 | Target Range3 |
|---|---|
| 24-hour urine calcium | <4 mg/kg body weight daily |
| Vitamin D | >20 ng/mL |
| †Assess more frequently following adjustments in calcium or vitamin D dose | |
Target-organ evaluations
As clinically indicated1,6:
- Renal ultrasound or CT scan
- CNS imaging
- Electrocardiogram
- Bone mineral density
- Ophthalmologic examination
Key management strategies
Calcium1:
- Calcium requirements can vary, ranging from less than 1 g/d up to 9 g/d.
- Calcium carbonate is most commonly used, but calcium citrate can be considered in certain clinical situations.
Active vitamin D1:
- Typical doses of calcitriol (active vitamin D) are between 0.25 μg/d and 2.00 μg/d.
- Ergo- or cholecalciferol (parent vitamin D) supplementation may be considered.
Thiazide diuretics1:
- Often used in the presence of hypercalciuria, as they promote calcium retention in the renal tubules.
- Serum potassium and magnesium should be monitored with diuretic use.
Magnesium6:
- Used if hypomagnesemia is present, which can be due to diuretic or proton pump inhibitor use.
Phosphate binders1:
- Only used in situations where serum phosphate levels are markedly elevated (eg, >6.5 mg/dL) and the calcium-phosphate product is of concern.
Dietary changes1:
- Patients with high serum phosphate levels may need to follow a low-phosphate diet.
- Patients with high urine calcium levels may need to follow a low-salt diet.
Hormone therapy may be considered for patients who are not adequately controlled.1
Some patients with chronic hypoparathyroidism require large amounts of calcium supplementation.7
BEYOND CALCIUM CONTROL