Hypercalcaemia

Question 1

Level for for hypocalcaemia

Answer 1

• Less than 2.6mmol/

Question 2

Commonest causes of hypercalcaemia

Answer 2

• Primary hyperparathyroidism
• Malignancy
• Could also be benign granulomatous - eg TB or sarcoidosis

Question 3

Malignancy vs primary hyperparathyroidism

Answer 3

• Malignancy is low PTH
• Normal-high PTH = primary hyperparathyroidism

Hypercalcaemia with supressed PTH is malignancy until proven otherwise

Question 4

Most common malignancies associated with hypercalcaemia

Answer 4

• Squamous cell epithelial tumours (secrete PTHrP)
• Large or advanced tumours
• Bone mets not always present

Question 5

Most common cause of primary hyperparathyroidism

Answer 5

Parathyroid adenoma

Question 6

Other causes primary hyperparathyroidism

Answer 6

• Parathyroid hyperplasia of multiple glands –> suggests genetic cause eg multiple endocrine neoplasia
• Very high (if more than 3.5mmol/L) could suggest parathyroid cancer but VERY RARE
• PT cancer can be associated with jaw tumours (hyperparathyroidism-jaw tumour syndrome)

Question 7

Clinical features hypercalcaemia

Answer 7

• Tiredness
• Generalised aches and pains
• abdominal pain
• Constipation
• Psychiatric symptoms
• Kidney stones

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* Polyuria
* Polydipsia
(from nephronic diabetes insipidus)

Question 8

What does severe metabolic parathyroid bone disease do?

Answer 8

Cystic appearance on x-ray - Brown tumours

Question 9

Investigations for hypercalcaemia - primary hyperparathyroidism suspected

Answer 9

• PTH
• Phosphate
• ALP - high bone turnover, common in vitD deficiency
• X-ray - lower bone density, subperiosteal erosions of phalanges in severe disease
• Renal USS - nephrocalcinosis

Question 10

What is familial hypocalciuric hypercalcaemia?

Answer 10

• Rare condition
• Caused by genetic defect in calcium sensing receptor
• Low urine calcium/creatinine ratio - how we determine it from primary hyperparathyroidism
• FH usually of mild hypercalcaemia
• Rule out before neck exploration

Question 11

How to locate parathyroid adenoma?

Answer 11

• Needs localisation prior to surgery
• Can be difficult if lesion small
• Parathyroid USS usually detects
• SESTAMIBI isotope scanning used alongside USS

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* Sometimes SPECT CT / MRI and 4-D CT is used

Question 12

Treatment hyperparathyroidism - surgery

Answer 12

• Surgery - Parathyroidectomy - considered if calcium more than 2.85 mmol/L or symptoms debilitating
• Younger patients often recommended surgery

Question 13

Medical management of hyperparathyroidism

Answer 13

• Calcium mimetics eg Cinacalcet

Question 14

How does acute severe hypercalcaemia present?

Answer 14

• Profound dehydration
• Renal impairement
• Need urgent admission