HyperPTH

Question 1

Physiology

Answer 1

SECRETED BY CHIEF CELLS
PTH secreted in response to ↓Ca2+ ↑osteoclast activity
↑Ca2+ and ↓PO4 reabsorption in kidney ↑ 1α-hydroxylation of 25OH-Vit D3

Question 2

2+ Presentation: ↑ Ca

Answer 2

Stones:
Renal stones
Polyuria and polydipsia (nephrogenic DI)
Nephrocalcinosis

Bones:
Bone pain
Pathological #s

Moans: depression

  Groans:
  Abdo pain
  n/v and constipation
  Pancreatitis
  PUD (↑gastrin secretion)

Other:
↑ BP (check Ca2+ in all with HTN)

Question 3

Causes of Primary Hyperparathyroidism

Answer 3

Solitary adenoma: 80%
Hyperplasia: 20%
Pathyroid Ca: <0.5%

Question 4

Investigations

Answer 4

↑Ca2+ + ↑ or inappropriately normal PTH, ↑ALP, ↓PO4

ECG: ↓QTc → bradycardia → 1st degree block

X-ray: osteitis fibrosa cystica → phalangeal erosions

DEXA: osteoporosis

Question 5

Treatment - general

Answer 5

General
↑ fluid intake
Avoid dietary Ca2+ and thiazides (↑ serum Ca)

Question 6

Treatment - surgical

Answer 6

Surgical: excision of adenoma
Hypoparathyroidism
Recurrent laryngeal N. palsy

Question 7

Causes of secondary hyperPTH

Answer 7

Vitamin D deficiency

Chronic renal failure

Question 8

Investigation results

Answer 8

↑PTH, ↓Ca, ↑PO4, ↑ALP , ↓vit D

Question 9

Treatment

Answer 9

Correct causes
Phosphate binders
With Ca: calcichew
W/o Ca: sevelamer, lanthanum
Vit D: calcitriol (active), cholecalciferol (innactive)
Cinacalcet: ↑ parathyroid Ca-sensitivity

Question 10

Tertiary hyperPTH + investigation results

Answer 10

Prolonged 2O HPT → autonomous PTH secretion ↑Ca2+, ↑PTH, ↓PO4, ↑ALP