Metabolic Medicine Flashcards
What are causes of raised ALP?
Cholestasis
Paget’s disease - isolated ALP
Osteomalacia - raised ALP, low calcium+phosphate
Bone mets - raised ALP + calcium
Hyperparathyroidism - raised ALP + calcium
Renal failure - raised ALP + low calcium
Pregnancy
What are the 2 main cause of hypercalcaemia?
Primary hyperparathyroidism + Malignancy (bone mets, myeloma, squamous cell lung cancer)
What are other causes of hypercalcaemia other than the 2 main causes?
Sarcoidosis Vitamin D intoxication Acromegaly Thiazide-like diuretics Addison's disease
What ECG finding is seen in hypercalcaemia?
Short QT
How does hypercalcaemia present?
Stones, groans, bones, moans
Bone pain
Renal stones
Depression
How is hypercalcaemia treated?
IV Sodium Chloride 0.9%
What are causes of hypocalcaemia?
Vitamin D deficiency (osteomalacia) CKD Hypoparathyroidism Pseudohypoparathyroidism Magnesium deficiency Acute pancreatitis
What are signs of hypocalcaemia?
Tetany - muscle twitching/cramping/spasm
Perioral parasthaesia
Trousseau’s sign
Chvostek’s sign
What is Trousseau’s sign?
Carpal spasm if brachial artery is occluded with blood pressure cuff
What is Chvostek’s sign?
Tapping the parotid causes the facial muscles to twitch
How is hypocalcaemia managed?
10ml calcium glutinate 10% over 10 mins
What ECG changes are seen in hyperkalaemia?
Tall tented T waves
Widened QRS
Small P waves
Prolonged PR interval
What are causes of hyperkalaemia?
AKI
Addison’s disease
Rhabdomyolysis
Drugs: ACEi, ARB, Spironolactone
How is the cardiac membrane stabilised in hyperkalaemia?
IV calcium gluconate
How is hyperkalaemia treated?
IV insulin - shifts potassium back into cells
oral calcium resonium - removes potassium
What are causes of hypokalaemia with ACIDOSIS?
Diarrhoea
Renal tubular acidosis
Acetazolamide
Partially treated DKA
What are causes of hypokalaemia with ALKALOSIS?
Vomiting Thiazide diuretics Loop diuretics Salbutamol Cushing's syndrome Hyperaldosteronism
What is seen on ECG in hypokalaemia?
Small/absent T waves Prolonged PR interval Prolonged QT interval ST depression U waves
How is hypokalaemia managed?
Potassium infusion - maximum of 10mmol an hour
What are causes of hypernatraemia?
Dehydration Osmotic diuresis e.g. HHS Diabetes insipidus Excess IV saline Cushing's Hyperaldosteronism
How is hypernatraemia managed?
Mild hypernatraemic dehydration: (146-149)
• Manage underlying cause
Moderate hypernatraemic dehydration (150-169)
• Slow fluid resus – avoid rapid infusion due to risk of cerebral oedema
What is the most important investigation for determining the cause of hyponatraemia?
Serum and urine osmolality
What are causes of hyponatraemia with a HIGH urine osmolality?
If patient is hypovolaemic.. think sodium depletion (renal)
Diuretics (thiazide, loop)
Addison’s
If patient is euvolaemic.. think…
SIADH
Hypothyroidism
What are causes of hyponatraemia with a LOW urine osmolality?
If patient is hypovolaemic.. think sodium depletion (non-renal)
Diarrhoea, vomiting, sweating, burns
If patient is euvolaemic/oedematous.. think water excess... Heart failure Liver cirrhosis Nephrotic syndrome Psychogenic polydipsia
How is hypovolaemic hyponatraemia managed?
IV saline – 0.9% Sodium Chloride
If serum sodium rises - supports diagnosis of hypovolaemic hyponatraemia
How is euvolaemic hyponatraemia managed?
SIADH –> Tolvaptan, Sodium, furosemide
Hypothyroidism –> levothyroxine
Fluid restrict
How is hyponatraemia treated if the patient is acutely unwell with seizures?
Hypertonic saline e.g. 3% sodium chloride
Be careful of risk of central pontine myelinosis
How is hypervolaemic hyponatraemia managed?
Fluid restriction
Treat underlying cause
How does central pontine myelinosis present?
Dysarthria, dysphagia, paraparesis or quadriparesis, seizures, confusion, and coma
Locked in syndrome
What is renal tubular acidosis?
A cause of metabolic acidosis due to a pathology in the tubules of the kidney
What is type 1 renal tubular acidosis? What electrolyte abnormality is seen? How is it treated?
Metabolic acidosis due to the distal tubule being unable to excrete hydrogen ions
Associated with renal stones
Causes a hypokalaemia and metabolic acidosis
Treatment = oral bicarbonate
What is type 2 renal tubular acidosis? What is the main associated condition? how is it treated?
Metabolic acidosis due to the proximal tubule being unable to reabsorb bicarbonate
Associated with Fanconi syndrome and OSTEOMALACIA
Hypokalaemia
Treatment = oral bicarb
What is type 4 renal tubular acidosis? What electrolyte abnormalities are seen? What is the treatment?
Metabolic acidosis due to reduced aldosterone (usually due to adrenal insufficiency)
Leads to hyperkalaemia
Treated with fludrocortisone and sodium bicarbonate
Treat the hyperkalaemia
What is the most common type of renal tubular acidosis?
Type 4
What is familial hypercholesterolaemia?
Autosomal dominant condition
High levels of LDL
Can lead to early cardiovascular disease
When should you suspect familial hypercholesterolaemia?
Total cholesterol level >7.5
Personal/family history of CVD event before 60 years
Tendon xanthomata
