Primary hyperparathyroidism
Overproduction of parathyroid hormone
- Abnormal gland continues to make calcium regardless of serum calcium level
Causes:
- *1. Solitary adenoma**
- *2. Multiple gland disease**
- *3. Parathyroid cancer**
Risk factors:
- Women > men
- Post menopause (50+)
Diagnosis:
- Elevated PTH
- Hypercalcemia
- Hypercalciuria
Treatment:
- Surgical parathyroidectomy
Solitary parathyroid adenoma
- Benign tumour in 1 of 4 glands
- Most common cause of primary hyperparathyroidism
Cause:
- Genetic mutation
- Inherited disorder (MEN I)
Presents:
- High serum PTH + calcium, low phosphate
Treatment:
- Reduce PTH + calcium (medical)
- Surgical resection
- *Hypoechoic solid lesion**
- Homogeneous
- Oval (~1cm)
- *Hypervascular**
- Arch
- Feeding vessel
- Differentials:*
- Lymph node*
- Thyroid nodule*
Multiple gland disease
- Parathyroid hyperplasia
- Parathyroid cells divide excessively
- Involves all 4 glands symmetrically - Multiple adenomas
- Adenomas in 2-3 glands
Present:
- Hyperparathyroidism
Treatment:
- Reduce PTH + calcium (medical)
- Surgical resection
- *Asymmetrically enlarged parathyroid glands**
- Difficult to differentiate sonographically*
Parathyroid cancer
- Rare
- Causes 1-2% of primary hyperparathyroidism
- Poor prognosis (invasive metastatic nature)
Presents:
- Very high serum calcium (>14mg/dL)
Treatment:
- Surgical resection
- *Heterogeneous mass**
- Internal cystic components
- Lobular contour
>2cm (lager than adenomas)
Hypervascular
Invasion of adjacent tissues
Differential = large adenoma
Secondary hyperparathyroidism
Overproduction of parathyroid hormone
- Normal PT glands make excess PTH due to chronic hypocalcemia
- Often patients with chronic renal failure
Presents:
- Symptoms of CKD
- Bone demineralisation
- Calcs in soft tissues + blood vessels
Treatment:
- Treat renal failure (dialysis, transplant)
US usually not necessary
