Hyperparathyroidism

Question 1

Primary hyperparathyroidism is a disorder of the ___________.

Answer 1

Parathyroid gland; most commonly caused by an adenoma in one of the glands

Question 2

What is the most common cause of primary hyperparathyroidism?

Answer 2

Adenoma of one of the glands causing excess secretion of parathyroid hormone leading to hypercalcemia, hypophosphatemia, and hypercalciuria

Question 3

What are the electrolyte abnormalities resulting from hyperparathyroidism? (3)

Answer 3

1. Hypercalcemia
2. Hypophosphatemia
3. Hypercalciuria

Question 4

What causes the symptoms of primary hyperparathyroidism?

Answer 4

Hypercalcemia

Question 5

What are the symptoms of primary hyperparathyroidism? (5)

Answer 5

Main symptoms caused by hypercalcemia

1. Increased thirst
2. Increased urine output
3. Constipation
4. Fatigue
5. Memory impairment

Question 6

What are the long term effects of hyperparathyroidism? (4)

Answer 6

1. CVD
2. Kidney stones
3. Osteoporosis
4. Fractures

Question 7

What are the aims of treatment of primary hyperparathyroidism?

Answer 7

Treatment is focused on cure through surgery

Other treatment options aim to reduce long-term complications and improve QoL

Question 8

What is the first line treatment of primary hyperparathyroidism?

Answer 8

Parathyroidectomy surgery

Unsuccessful surgery requires MDT review

Question 9

What screening should be carried out for all patients with primary hyperparathyroidism? (2)

Answer 9

1. CVD risk assessment and prevention

2. Assessment of osteoporosis and fracture risk

Question 10

Women with primary hyperparathyroidism are at increased risk of ____________ in pregnancy

Answer 10

hypertensive disease

for pregnant women, the management and monitoring of primary hyperparathyroidism should be discussed with a multidisciplinary team at a specialist centre

Question 11

Treatment with __________ may be considered for patients with primary hyperparathyroidism if surgery has been unsuccessful, is unsuitable, or has been declined AND they have an elevated albumin-adjusted serum Ca level with or without symptoms of hypercalcemia

Answer 11

cinacalcet (unlicensed)

Question 12

In secondary care, __________ should be measured and supplementation with _________ offered for people with a probable diagnosis of primary hyperparathyroidism if needed

Answer 12

Vitamin D levels

Vitamin D

Question 13

What is the mechanism of action of cinacalcet?

Answer 13

Oral calcimimetic agent that increases the senitivity of Ca-sensing receptors to the activity of extra-cellular calcium
These Ca-sensing receptors on the surface of PT gland cells also regulates the release of PTH

Question 14

To reduce fracture risk for people with primary hyperparathyroidism who have an increased fracture risk, a __________ can be considered.

Answer 14

bisphosphonate

However, do not offer bisphosphonates for chronic hypercalcaemia of primary hyperparathyroidism

Question 15

_________ should NOT be offered for patients with chronic hypercalcemia of primary hyperparathyroidism

Answer 15

Bisphosphonates

Question 16

What are the primary actions of PTH? (4)

Answer 16

1. Increase release of Ca from bones (and PO4)
2. Increased conservation of Ca by the kidneys
3. Increased absorption of Ca from GIT
4. Decrease renal reabsorption of PO4 (PCT)

Question 17

Why is it important that PO4 is excreted when attempting to increase serum Ca?

Answer 17

PO4 binds Ca in the blood, forming salts that are insoluble and resulting in reduced serum free (ionized) Ca

Thus, following release of Ca and PO4 from the bones by PTH, PO4 must be excreted in order to effectively raise serum Ca

Question 18

What are the indications for cinacalcet? (3)

Answer 18

1. Secondary hyperparathyroidism (patients with ESRD on dialysis)
2. Hypercalcemia in parathyroid carcinoma
3. Primary hyperparathyroidism (in patients where parathyroidectomy is inappropriate)

Question 19

What is the main contraindication to use of cinacalcet?

Answer 19

Hypocalcemia

Question 20

What are the main causes of secondary hyperparathyroidism? (2)

Answer 20

1. Kidney failure (CKD)

2. Vitamin D deficiency (lack of sunlight OR malabsorption from small bowel disease, pancreatic insufficiency, etc)

Question 21

What are the monitoring requirements for cinacalcet?

Answer 21

Primary hyperparathyroidism and parathyroid carcinoma:

measure serum-calcium concentration before initiation of treatment and within 1 week after starting treatment or adjusting dose, then every 2–3 months

Secondary
hyperparathyroidism:

measure serum-calcium concentration before initiation of treatment and within 1 week after starting treatment or adjusting dose, then monthly thereafter.
Measure parathyroid hormone concentration 1–4 weeks after starting treatment or adjusting dose, then every 1–3 months

Question 22

How should cinacalcet be taken?

Answer 22

Manufacturer advises capsules containing granules should be opened and the granules sprinkled on to a small amount of soft food (apple sauce or yogurt) or liquid, then administered immediately. Capsules should not be swallowed whole.

Question 23

What additional information should be given to patients taking cinacalcet?

Answer 23

patients and their carers should be counselled on the symptoms of hypocalcaemia and importance of serum-calcium monitoring

Question 24

What are the symptoms of hypocalcemia? (6)

Answer 24

1. Paresthesias
2. Muscle spasms
3. Cramps
4. Tetany
5. Circumoral numbness
6. Seizures