Hypercalcaemia Flashcards
What is Hypercalcaemia
Calcium levels <2.6
At what point does hypercalcamia need to be treated
> 3.0
What should be done if calcium levels are >3.5
Requires urgent correction due to risk of dysrhythmia and coma
What categories can the causes of hypercalcaemia be put into
Parathyroid mediated
Non-Parathyroid mediated
Medications
Miscellaneous
What are the most common parathyroid mediated cause of hypercalcaemia
Primary hyperparathyroidism (sporadic) (most common)
Multiple endocrine neoplasia (MEN)
What is the most common Non-Parathyroid mediated causes of hypercalcaemia
Hypercalcaemia of malignancy
Vitamin D intoxication
When should you consider medicine as a cause of hypercalcaemia
Medicines should be considered of there is a slow rise in calcium
Whats the most common medicine that can cause hypercalcaemia
Thiazide diuretics
What are the clinical features of Hypercalcaemia
Polyuria
Polydipsia
nephrolithiasis
Anorexia
Nausea and vomitting
Muscle weakness
Decreased concentration
Shortning of QT interval
Why is the rate of calcium increase important
Hypercalcaemia is generally better tolerated if the rate of increase has been slow.
What investigations should you do for hypercalcaemia
PTH (most important)
U&Es Ca PO4 Alk phos Myeloma screen Serum ACE Consider ECG
What is first line treatment for hypercalcemia
Rehydration – 0.9% Saline 4-6 litres over 24 hours – Monitor for fluid overload – Consider dialysis if severe renal failure
After rehydration, intravenous bisphosphonates (take couple of days to work) – Zolendronic acid 4mg over 15 mins – Give more slowly and consider dose reduction if renal impairment – Calcium will reach nadir at 2-4 days.
What is Primary hyperparathyroidism
Primary hyperparathyroidism is a condition in which one or more of the parathyroid glands makes too much PTH.
What is the epidemiology of Primary hyperparathyroidism
Female: male = 3:1
Incidence peaks 50-60 years
Whats the causes of Primary hyperparathyroidism
85% parathyroid adenoma
15% four gland hyperplasia
<1% MEN type 1 or 2A
<1% parathyroid carcinoma
Whats the presentation of Primary hyperparathyroidism
Usually asymptomatic
What is the aim of investigations for
Primary hyperparathyroidism
To confirm diagnosis then find affects of hypercalcaemia
What investigations should be carried out for Primary hyperparathyroidism
Ca,
PTH
U&Es: check renal function
Abdominal imaging: renal calculi
DEXA: osteoporosis
Spot urinary calcium/creatinine ratio
24 hour urinary calcium:
Why do you do a Spot urinary calcium/creatinine ratio
To exclude Familial hypocalciuric hypercalcaemia … A RARE MIMIC
What is the treatment for primary hyperparathyroidism
SURGICAL – definitive treatment. Curates 95% of people.
Medical
What are indications for surgery primary hyperparathyroidism
Presence of symptoms due to hypercalcaemia
High serum calcium
Osteoporosis
Reduced GFR or presence of kidney stones
<50 years
What is the medical management of primary hyperparathyroidism
Generous fluid intake (2-3 l/day)
Vitamin D replacement Cinacalcet
What is Cinacalcet
Acts as a calcimetic and mimics the effect of calcium on the calcium sensing receptor on Chief cells, this leads to a fall in PTH and subsequently calcium levels) – expensive
What is Familial hypocalciuric hypercalcaemia (FHH)
Autosomal dominant disorder of the calcium sensing receptor (runs in families)
