Hyperparathyroidism Flashcards
Hyperparathyroidism is when there are high levels of parathyroid hormone in the circulation. There are 3 types of hyperparathyroidism, which of these is most common?
1 - tertiary
2 - secondary
3 - primary
3 - primary
Primary = tumour of parathyroid gland
Secondary = low vitamin D or CKD
Tertiary = Prolonged secondary leading to hyperplasia of parathyroid gland
85%: solitary adenoma
10%: hyperplasia
4%: multiple adenoma
1%: carcinoma
What is the incidence of primary hyperparathyroidism?
1 - 4000 cases per 100,000
2 - 400 cases per 100,000
3 - 40 cases per 100,000
4 - 4 cases per 100,000
3 - 40 cases per 100,000
More common in females 3:1 ratio
What age does the incidence of primary hyperparathyroidism peak at?
1 - 15-30
2 - 30-45
3 - 50-65
4 - >70
4 - >70
Which of the following is NOT a risk factor for primary hyperparathyroidism?
1 - Male sex
2 - Older age
3 - Family history
4 - all of the above
1 - Male sex
More common in females, 3:1 ratio
There are 4 parathyroid glands located on the back of the thyroid gland. Which cell in the parathyroid glands secretes parathyroid hormone?
1 - follicular cells
2 - chief cells
3 - parietal cells
4 - langerhans cells
2 - chief cells
When calcium is low in the blood parathyroid hormone is released in an attempt to increase calcium levels. Which of the following is NOT a key site where parathyroid hormone receptors can be found and contribute towards maintaining sufficient levels of calcium in the circulation?
1 - bone = binds osteoblasts and recruits osteoclasts for bone resorption
2 - kidney = reduces Ca2+ excretion
3 - lungs = increase ACE production
4 - GIT = increases Ca2+ in small intestines
3 - lungs = increase ACE production
Bone = osteoblasts activate osteoclasts that break down bone causing increased Ca+2 and phosphate in the blood
If a patient has hyperparathyroidism, they will experience hypercalcaemia as the negative feedback in the parathyroid is dysfunctional, so lots of parathyroid is released. Which of the following is NOT a typical clincal feature of hypercalcaemia?
1 - increased risk of kidney and gall bladder stones
2 - bone pain
3 - osteopenia and osteoporosis
4 - abdominal pain, constipation, nausea + vomiting
5 - psychotic overtones
1 - increased risk of kidney and gall bladder stones
Does increase kidney stones, but NOT gall bladder stones
Psychic overtones includes:
- Fatigue
- Depression
- Memory impairment
Patients may also present with polyuria, paresthesia and muscle cramps.
When trying to diagnose hyperparathyroidism, it is important to measure which 2 of the following together?
1 - U&Es
2 - adjusted Ca2+
3 - parathyroid hormone
4 - thyroid hormone
2 - adjusted Ca2+
3 - parathyroid hormone
In primary hyperparathyroidism BOTH will be high
What is the definition of hypercalcaemia when the serum Ca2+ has been adjusted?
1 - >2mmol/L
2 - >2.6mmol/L
3 - >3mmol/L
4 - >3.6mmol/L
2 - >2.6mmol/L
If a patient presents with symptoms of hypercalcaemia but the rise in Ca2+ is rapid, is this likely to be primary hyperparathyroidism?
- No
Typically a slow disease occurring months to years
Which of the following tests would be useful to rule out non-parathyroid gland causes of hypercalcaemia?
1 - estimated glomerular filtration rate (eGFR) and creatinine (AKI or CKD)
2 - serum and urine protein electrophoresis, and urine Bence-Jones protein (myeloma)
3 - FBC to exclude haematological malignancy
4 - LFTs (liver metastasis/systematic diseases)
5 - DEXA (bone health and risk of osteopenia/osteoporosis)
6 - all of the above
6 - all of the above
Imaging may be used if malignancy is suspected
The most common differential for primary hyperparathyroidism is malignancy. Which 2 of the following are the most likely mechanisms?
1 - pituitary adenoma
2 - PTH-related-protein (PTHrP) secreting tumours
3 - Osteolytic lesions (e.g. bone metastasis and multiple myeloma)
4 - metastatic malignancy
2 - PTH-related-protein (PTHrP) secreting tumours
3 - Osteolytic lesions (e.g. bone metastasis and multiple myeloma)
Squamous cell carcinoma is common in lung cancer
In hypercalcaemia of malignancy is serum PTH high or low?
- low
Which of the following would be present in secondary hyperparathyroidism?
- high PTH to try and increase C2+
- low/normal Ca2+ due to CKD and/or low vitamin D levels
Which of the following would be present in primary hyperparathyroidism?
- high PTH due to tumour
- high Ca2+ due to high PTH