Endocrinology- Hypercalcaemia Flashcards
At what concentration of serum calcium does hypercalcaemia occur?
> 2.6mmol/L
What are the two common causes of hypercalcaemia?
Primary hyperparathyroidism and malignancy
What is typical of PTH levels in primary hyperparathyroidism and malignancy, allowing them to be distinguished between?
Primary hyperparathyroidism- Normal/high PTH
Malignancy- Low PTH
What are malignant causes of hypercalcaemia usually associated with?
Squamous cell epithelia tumours- Due to the secretion of PTH-related peptide
Normally large or advanced tumours
What 2 other conditions can hypercalcaemia with a low PTH be associated with?
TB or sarcoidosis
What is the most common cause of primary hyperparathyroidism?
A single parathyroid adenoma
What could parathyroid hyperplasia in more than one gland suggest?
A genetic cause- e.g. multiple endocrine neoplasia
What could, in rare cases, a serum calcium concentration of >3.5mmol/L suggest?
Parathyroid cancer
What can parathyroid cancer occur in association with? What is the name of the condition?
Jaw tumours - (hyperparathyroidism- jaw tumour syndrome)
How is primary hyperparathyroidism discovered?
Mostly asymptomatic, discovered incidentally via blood tests
What are the non-specific symptoms of primary hyperparathyroidism?
Tiredness
General aches and pains
What are the specific symptoms of primary hyperparathyroidism?
Polyuria Polydipisa- due to nephrogenic diabetes insipidus Abdominal pain and constipation Psychiatric symptoms 5% get kidney stones
What is unique about the appearance of severe metabolic parathyroid bone disease on X-rays?
Classical cystic appearance (‘brown tumour’)
What is common of PTH and phosphate levels in primary hyperparathyroidism presenting with hypercalcaemia?
High/non-suppressed PTH
Low phosphate
What 2 things does high ALP reflect?
Increased bone turnover
Possible co-existing Vitamin D deficiency§
What 3 clinical features may be present in a patient with hypercalcaemia?
- Reduced bone density-especially around distal radius
- Nephrocalcinosis
- Sub-periosteal erosion of the phalanges (in severe cases)
What is Familial Hypocalciuric Hypercalcaemia?
Rare condition caused by genetic defect in calcium sensing receptor
What distinguishes FHH from primary hyperparathyroidism?
Low urine calcium/ creatinine ratio
How is the parathyroid adenoma localised?
Isotope scanning alongside ultrasound or CT
At what concentration of serum calcium should surgery be considered for hyperparathyroidism?
> 2.85mmol/L
When are patients usually recommended for surgery for hyperparathyroidism?
If symptoms are debillitating
If the patient is young
If the patient presents with severe acute hypercalcaemia
If surgery is not desirable, what methods are put in place for hyperparathyroidism?
Medical management / observation
Calcimimetic drugs in order to lower calcium levels
What does a patient with acute severe hypercalcaemia present with?
Profound dehydration
Renal impairment
