Parathyroid Flashcards
Primary hyperparathyroidism
- 80% arises in clonal expansion of PTH secreting cells within a single gland
- 10-15% of cases 4 gland hyperplasia
- 4% are the product of adenomatous expansion in 2-3 glands
Syndromes to exclude
MEN1 (HPT, Pa, Pi, Co, Ca) Wermer’s
- PHPT (100%)
- Pancreas, gastrin, insulin, vip, somatostat, glucagonomes
- Prolactine
- Corticosurrenals
- Carcinoid
- Ovary/testicular
MEN2a (HPT, Phep, Thyr) Sipple’s
- Hyperparathyroidism (20%)
- Pheochromocytome (8-60%)
- notalgic paresthesia
- Medullary Thyroid Carcinoma (100%)
FHH familial hypocalciuric hypercalcemia (24h urine, less than 100mg in 24h is diagnostic)
Diagnosis
high blood calcium
low blood phosphate
high intact PTH
exclude :
- thiazidic
- hypoalbuminemia
- low Vitamin D
if Vit D low, substitute and repeat
Indication
Symptomatic Asymptomatic with : - Hypercalcemia - > 400mg 24h urinary calcium - Clearance < 60mL/min or lithiasis - T Score < -2.5
Localisation
Sestamini Spec CT + US (95%) localisation
Intra-operative Lab
Intact PTH must fall 50% in 10 minutes
Parathyroid Carcinoma
very high Ca and PTH
En bloc resection + thyroid lobe +/- Neck dissection
Secondary hyperparathyroidism
PTH resistance due to chronic renal insufficiency or low vitamin D
Not enough calcitriol is synthetized.
Seldom :
- alimentary not enough calcium, too much phosphorous
- paraneoplasic
Recurrence
Differentiate between recurrence and persistence
- Redo US + Sestamibi PETCT
MRI T2 including mediastinum