Hypercalcaemia

Question 1

What is the normal role of the parathyroid glands?

Answer 1

1. Secrete PTH

ACTION ON BONE
-Increases osteoclasts activity to release Ca2+ into the blood (in cases of hypocalcaemia)

ACTION ON KIDNEY

• Increases reabsorption of calcium from kidney tubules
• Increases activity of 1a hydroxylase = more activation of vitamin D = increase intestinal absorption of calcium

Question 2

What are the common causes of hypercalcaemia?

Answer 2

1. Bone metastases (lung & breast)*
2. Hyperparathyroidism*
3. Myeloma
4. Sarcoidosis
5. Thyrotoxicosis
6. Addison’s Disease
7. Acromegaly
8. Paget’s Disease
9. Familial hypocalciuric hypercalcaemia

Question 3

What are the symptoms of hypercalcaemia?

Answer 3

‘Bones, stones, psychic moans, groans’

1. Painful bones +/- fractures
2. Renal stones
3. Abdominal pain
4. Depression
5. Polyuria
6. Polydipsia

Question 4

What are the investigations for hypercalcaemia?

Answer 4

BLOODS

1. Ca2+ = raised
2. PTH = possibly raised
3. TFTs = thyrotoxicosis
4. Vitamin D, tumour markers, urinary Ca2+

IMAGING

1. ECG = shortened QTC interval
2. Bone scan = reduced bone density
3. CXR = tumour
4. Mammogram = tumour

Question 5

What is the management of hypercalcaemia?

Answer 5

1. Aggressive fluid rehydration to correct volume deficits
2. Co-administration of furosemide
3. Consider catheterisation and CVP monitoring for fluid balance
4. Monitor U&E, Ca2+ and Mg 2+ daily
5. After balance corrected consider bisphosphanates
6. Treat any underlying causes
   - Sarcoidosis = steroids
   - Bone mets = radiotherapy
   - Hyper-PTH = surgery

Question 6

What are the complications of hypercalcaemia?

Answer 6

Renal failure
Arrhythmias
Osteopenia
Renal stones
Peptic ulcers
Pancreatitis