Magnesium Metabolism

Question 1

Is magnesium mostly intracellular or extracellular

Answer 1

Intracellular cation

Question 2

Main function of magnesium

Answer 2

Stabilise excitable membrane

Question 3

Percentage of magnesium filtered at glomerulus

Answer 3

70%

Question 4

Percentage of magnesium reabsorbed at loop of henle

Answer 4

50-70%

Question 5

Hormone that enhances magnesium réabsorption

Answer 5

PTH

Question 6

Definition of hypomagnesemia

Answer 6

Concentration Below 0.75-1mmol/L

Question 7

Causes of hypomagnesemia

Answer 7

M
Starvation
Malnutrition
Alcoholism
Parenteral alimentation
Prolonged vomiting/nasogastric aspiration
Chronic diarrhoea/laxative abuse
Malabsorption
Small bowel bypass surgery
Fistulae
Diuretic therapy
Alcohol
Tubulotoxic drugs:
Gentamicin
Cisplatin
Volume expansion
Diabetic ketoacidosis
Post-obstructive diuresis
Recovery from acute tubular necrosis
Inherited tubular transport defect:
Bartter’s syndrome
Gitelman’s syndrome
Primary renal magnesium wasting
Acute pancreatitis
Foscarnet therapy
Proton pump inhibitor therapy
Hungry bone syndrome
Diabetes mellitus