Hypercalcemia - Meran Flashcards
What does low potassium cause in the heart?
VF
What does high potassium cause in the heart?
Asystole
Symptoms of hypercalcemia
BONES - bony pain
MOANS - depression
GROANS - renal stones, pancreatitis, pain
STONES - renal stones
Band keratopathy
Polyuria and polydipsia
Symptoms of hypocalcemia
CATS go numb
tetany
arrhythmia
numbness
Case 1 - a patient comes in with depression, smith’s fracture and haematuria. What’s going on?
Hypercalcemia - 2.82 (2.20-2.60)
What is a key investigation for hypercalcemia?
Plasma calcium levels
PTH levels
Three key causes of hypercalcemia -
Primary hyperparathyroidism (community)
Cancer (hospital)
Sarcoidosis
Smith’s vs Colle’s fracture
Colles = FOOSH, distal radius (literally the bit touching the wrist) is displaced posteriorly (DR CPD)
Smith = fall onto back of hand, distal radius has VOLAR displacement aka towards the palm
What does volar mean?
Towards the palm
What is another name for the skeletal changes which occur in primary hyperparathyroidism?
Osteitis fibrosa et cystica
How do you investigate renal colic?
Non contrast CT KUB
or USS if someone is pregnant or a child
+ urinalysis
+ urea and creatinine
+ stone analysis if unclear
Which renal stones show up opaque?
Calcium stones
Management of renal colic
Lithotripsy
Hydration
Analgesia
cystoscopy? lithotomy?
Which stones are radiolucent?
Uric acid - gout
How can you prevent renal colic?
Hydration
Thiazide diuretics (if people are stone formers)
Vit D metabolism
UV turns cholestrol to 7-dehydroxycholestrol
Liver turns 7-dehydrocholestrol / D3/cholecalciferol into 25-hydroxycholecalciferol using 25 hydroxylase; this is through first pass metabolism.
Kidney converts this into 25-vitamin D3 into 1,25 vitamin D3 through 1 alpha hydroxylase. This is a rate limiting step.
Which step is rate limiting in vit D metabolism?
1 alpha hydroxylase step - kidney
What is another name for calcidiol?
25 hydroxyl cholecalciferol / 25-Vit D3
What is another name for calcitriol?
1,25 hydroxy cholecalciferol
Where does PTH act in the metabolism of vitamin D?
PTH stimulates the 1 alpha hydroxylase enzyme, produced by the kidneys.
What level of calcium is considered really bad hypercalcemia?
Above 3.0mmol/L
What symptoms might someone with severe hypercalcemia present with?
Confusion
Drowsiness
Seizures
Renal failure
Dehydration
How do you manage hypercalcemia in an emergency?
Get IV access - cannula or central line (through subclavian)
Calciuresis:
0.9% saline 4L
Furosemide
Keep hydrated
Arrange for surgery
How long does it take for the emergency treatment of hypercalcemia to work?
A few days - gotta be patient
What can be used as a last resort? What is the side effect of this?
Bisphosphonates - e.g. IV pamidronate 30-60mg.
However then this locks into the bone and causes hypocalcemia when the patient has their parathyroid glands removed.
What are Looser’s zones?
caused by vit D deficiency; pseudofractures (not to do with primary hyperparathyroidism)
What would a hand x-ray show in hypercalcemia?
Radial aspect always shows cystic changes.
Bilateral hilar lymphadenopathy
Sarcoidosis
TB
What would the histology show
Multinucleate giant cells
Why does sarcoidosis cause hypercalcemia?
Macrophages in giant cells PRODUCE 1 alpha hydroxylase so they convert 25-OH vitamin D3 into 1,25-OH vitamin D, which then acts on the bone and gut to move more calcium into the blood.
What does histology of sarcoidosis show?
Giant multinucleated cells
How do you treat sarcoidosis?
Prednisolone - treats both the lung symptoms and the sarcoidosis
What’s the side effect of prednisolone?
Hyperglycemia, cushings syndrome, thin skin, easy bruising etc
Why does cancer cause hypercalcemia?
Some cancers produce PTHrP which makes the cancers invade bone more easily
How do you treat cancer hypercalcemia?
Fluids + bisphophonate
How do bisphosphonates work in cancer hypercalcemia
Osteoblasts make bone with bisphosphonate. However bisphosphonate is resistant to osteoclast activity (stimulated by PTHrP from cancer) so it reduces the pain from bony mets.
