Hyperparathyroidism Flashcards
Define Primary Hyperparathyroidism?
Increased secretion of PTH unrelated to the plasma calcium concentration
Define Secondary Hyperparathyroidism?
Increased secretion of PTH secondary to hypocalcaemia
Define Tertiary Hyperparathyroidism?
Autonomous PTH secretion following chronic secondary hyperparathyroidism
What is the aetiology of Primary Hyperparathyroidism?
Parathyroid Adenoma
Parathyroid Hyperplasia
Parathyroid Carcinoma
MEN Syndrome
What is the aetiology of Secondary Hyperparathyroidism?
Chronic renal failure
Vitamin D deficiency
What is the epidemiology of Hyperparathyroidism?
Primary - incidence of 5/100,000
Twice as common in FEMALES
Peak incidence: 40-60 yrs
What are the signs and symptoms of Primary Hyperparathyroidism?
Many patients have mild hypercalcaemia and may be asymptomatic
What are the symptoms/signs of Hypercalcaemia?
Polyuria Polydipsia Renal Calculi Bone pain Abdominal Pain Nausea Constipation Psychological Depression Lethargy
What are the presenting symptoms and signs of Secondary Hyperparathyroidism?
May present with signs/symptoms of hypocalcaemia or of the underlying cause (e.g. renal failure, VIT D deficiency)
What general investigations would you do for Hyperparathyroidism?
U&Es Serum calcium Serum Phosphate Albumin ALP Vit D PTH Renal US
What would you see on a serum calcium for the different Hyperparathyroidisms?
high in primary and tertiary, low/normal in secondary
What would you see on the Serum Phosphate for the different Hyperparathyroidisms?
Low in primary and tertiary, high in secondary
What investigations would you do specifically for Primary Hyperparathyroidism?
Hypercholoraemic Acidosis
Normal Anion gap
Due to PTH inhibition of renal reabsorption of bicarbonate
Urine
Why do we do Urine tests for Primary Hyperparathyroidism?
High PTH in the presence of high calcium can also be caused by familial hypocalcuric hypercalcaemia (FHH)
What can we use to differentiate between primary Hyperparathyroidism and FHH?
Calcium: creatinine clearance ratio
How can we use Renal US for Hyperparathyroidism invesigation?
Can visualise renal calculi
What is the management plan for Acute Hypercalcaemia?
IV fluids
Avoid factors that exacerbate hypercalcaemia (e.g. thiazide diuretics)
Maintain adequate hydration
Moderate calcium and Vit D intake
What is the surgical management of Hyperparathyroidism?
Subtotal parathyroidectomy
Total Parathyroidectomy
What is the Secondary Hyperparathyroidism management?
Treat underlying cause (e.g. renal failure)
Calcium and Vit D supplements may be needed
What are the complications for Primary Hyperparathyroidism?
Increased bone resorption
Increased tubular calcium reabsorption
Increased 1a-hydroxylation of Vit D
All of these lead to hypercalcaemia
What are the complications of Secondary Hyperparathyroidism?
Increased stimulation of osteroclasts and increased bone turnover
This leads to osteitis fibrosa cystica
What are the complications of surgery in the treatment in Hyperparathyroidism?
Hypocalcaemia
Recurrent laryngeal nerve palsy
What is the prognosis for patients with primary Hyperparathyroidism?
Surgery is curative for benign disease in most cases
What is the prognosis for secondary and tertiary Hyperparathyroidism?
Same as chronic renal failure
