secondary/tertiary hyperparathyroidism

Question 1

what is secondary hyperparathyroidism

Answer 1

1. low calcoum or high phosphate
2. reactive hyperplasia of parathyroid glads
3. PTH secretion is high

Question 2

Name 3 causes of secondary hyperparathyroidism?

Answer 2

1. chronic kidney disease

• impaired phosphate secretion
• high phosphate –> high PTH
• reduced vit D -> reduced calcium reabsorbtion –> High PTH
  2. Vitamin D deficiency
  3. Malnutrition

Question 3

2nd HPT - lab results for

• calcium
• phosphorous
• ALP
• PTH

Answer 3

1. Calcium = normal/low
2. Phosphate = normal/high
3. ALP = high
4. PTH = high

Question 4

Mx of 2nd HPT

Answer 4

1. treat underlying cause e.g. CKD
2. tx hyperphosphatemia
   - restrict phosphate in diet
3. Vitamin D supplement - ergocalciferol

Question 5

What is the definition of ‘tertiary hyperparathyroidism’

Answer 5

1. hypercalcaemia from untreated sHPT
2. refractory/autonomous PTH secretion
3. hypercalcaemia