WISEMD Hypercalcemia

Question 1

Where is calcium absorbed? Where is it stored? Where is it excreted?

Answer 1

1) Small bowel
2) Bones
3) Kidneys

Question 2

What regulates calcium and when it is secreted? What does this upregulate?

Answer 2

1) PTH regulates levels of calcium and is secreted by the parathyroid glands in response to low serum calcium levels
2) Increases intestinal and renal absorption of calcium, and increases bone breakdown

Question 3

What enhances the effects of PTH? Where is this obtained from?

Answer 3

1) Vitamin D

2) Food, sunlight

Question 4

What are the two most common causes of hypercalcemia (over 90%)?

Answer 4

1) Hyperparathyroidism

2) Malignancy (Bone metastasis or produces PTH-related peptide, such as small cell carcinoma of the lung)

Question 5

Is PTH elevated or decreased in primary hyperparathyroidism? What about calcium

Answer 5

1) Elevated PTH (10% have normal PTH)

2) Elevated calcium

Question 6

What are the two causes of primary hyperparathyroidism?

Answer 6

1) Parathyroid adenoma (70%)

2) Parathyroid hyperplasia (Remaining amount)

Question 7

How is primary hyperparathyroidism treated in symptomatic patients? In asymptomatic patients?

Answer 7

1) Parathyroidectomy

2) May need surgery depending on age, degree of osteoporosis, renal disease, or hypercalcemia

Question 8

Which patients develop secondary hyperparathyroidism? What is it developed in response to? What does this response stimulate?

Answer 8

1) Seen in patents with severe renal disease or vitamin D deficiency
2) In response to low vitamin D levels, low serum calcium levels, or high serum phosphate levels
3) Stimulates parathyroid hyperplasia to increase PTH production

Question 9

What are complications of secondary hyperparathyroidism if not corrected?

Answer 9

1) Renal osteodystrophy
2) Vascular calcifications
3) Calciphylaxis

Question 10

What is the treatment of secondary hyperparathyroidism if patients are not on dialysis? What about if they are on dialysis?

Answer 10

1) Vitamin D supplementation (Calcitriol)
2) Calcimimetics (Cinacalcet), which increases sensitivity of the calcium-sensing receptor (CaSR)
3) Phosphate binders

Question 11

What is tertiary hyperparathyroidism?

Answer 11

Occurs after successful renal transplant when secondary hyperparathyroidism persists and becomes autonomous

Question 12

When is parathyroidectomy indicated for tertiary hyperparathyroidism?

Answer 12

1) Calciphylaxis
2) Severe hypercalcemia
3) Severe pruiritis
4) Severe renal osteodystrophy
5) Severe unexplained myopathy

Question 13

What is the helpful pneumonic for remembering symptoms of hyperparathyroidism?

Answer 13

1) Painful bones
2) Renal stones
3) Abdominal groans
4) Psychiatric moans/overtones

Question 14

What are the symptoms of hyperparathyroidism?

Answer 14

1) Osteoporosis or bone pain
2) Kidney or bladder stones
3) Abdominal pain, constipation
4) Depression

Question 15

What other personal (not family) questions should be asked during a history of hyperparathyroidism that might explain the etiology?

Answer 15

1) Radiation exposure
2) Prior cancer
3) Renal disease
4) Vitamin D deficiency
5) Excessive calcium or vitamin D intake
6) Lithium or hydrochlorothiazide usage

Question 16

Why is it important to ask questions about family history?

Answer 16

Familial endocrinopathies:
Multiple Endocrine Neoplasia Syndrome
1) MEN1 - Pituitary, parathyroid, pancreas
2) MEN2A - Medullary thyroid cancer, hyperparathyroidism, pheochromocytosis
Other very rare syndromes

Question 17

What laboratory studies should be done for hyperparathyroidism?

Answer 17

1) Ionized calcium, calcium, phosphorus, chloride, and PTH levels (Sources of malignancy)
2) Electrolytes, BUN/Cr (Renal disease)
3) 24 hour urine calcium collection (Familial hypocalceuric hypercalcemia)
4) Vitamin D level (Deficiency)
5) Albumin (To calculate absolute calcium level, which is usually higher than the reported lab value)

Question 18

Which lab studies will usually be elevated in patients with hyperparathyroidism? Which will be low?

Answer 18

1) Serum calcium, ionized calcium, PTH, chloride

2) Phosphorus

Question 19

What imaging should you begin with for hyperparathyroidism?

Answer 19

Neck/thyroid ultrasound to evaluate for parathyroid adenoma and possible concomitant thyroid nodule

Question 20

What is another common imaging modality used after ultrasound? What does it evaluate for? What does delayed imaging on this scan show?

Answer 20

1) Sestamibi scan
2) Parathyroid adenoma, ectopic location, concomitant thyroid nodule
3) Delayed imaging increases sensitivity and specificity for adenoma

Question 21

When is surgery indicated for hyperparathyroidism?

Answer 21

1) Symptomatic hyperparathyroidism

2) Asymptomatic hyperparathyroidism meeting NIH criteria

Question 22

When can focused parathyroidectomy be accomplished?

Answer 22

1) If preoperative imaging confirms location

2) Intraoperative PTH measurements should decrease by 50% in 10 minutes

Question 23

What are immediate post-operative complications of a parathyroidectomy?

Answer 23

1) Recurrent laryngeal nerve injury. Check for quality and strength of voice, and any hoarseness
2) Hypocalcemia presents with perioral numbness, numbness in the fingers or toes, and Chvostek’s sign
3) Neck hematoma is life threatening because blood is trapped under the incision and the patient cannot breathe. Listen for inspiratory stridor

Question 24

What are long-term post-operative complications of a parathyroidectomy?

Answer 24

1) Hypocalcemia due to bone hunger due to severe osteoporosis or hypoparathyroidism due to parathyroid gland damage (low PTH level). Make sure to continue calcium or vitamin D repletion
2) Hypercalcemia can be persistent or recurrent and requires you to check calcium postoperatively