Calcium Disorders Flashcards
List clinical features of hypercalcaemia
Thirst, dehydration Confusion Polyuria Myopathy Osteopenia, fractures Hypertension Abdo pain (renal stones, pancreatitis)
List the main causes of hypercalcaemia
Hyperparathyroidism Malignancy Drugs (vit D, thiazides) TB, sarcoidosis High cell turnover (Paget's) FHH
If you could do one test to investigate hypercalcaemia, what would you do?
Measure PTH levels
Outline management of hypercalcaemia
Fluid replacement
Loop diuretic
Biphosphonate
What is the difference between primary, secondary and tertiary hyperparathyroidism?
Primary: overactivity of PT gland due to adenoma
Secondary: physiological response to low Ca
Tertiary: PT becomes autonomous after years of secondary hyperparathyroidism
In primary hyperparathyroidism, PTH levels are high/low and calcium levels are high/low
PTH high
Calcium high
In secondary hyperparathyroidism, PTH levels are high/low and calcium levels are high/low
PTH high
Calcium low
What investigation is done for hyperparathyroidism?
Sestamibi scan - localises adenoma
What is FHH?
Familial hypercalciuric hypercalcaemia
Autosomal dominant disease where CaSR is mutated
List clinical features of hypocalcaemia
Paraesthesia Muscle cramps/tetany/weakness Fatigue Bronchospasm Chovstek sign Trousseau sign
What is Chovstek sign in hypocalcaemia?
Tapping over facial nerve produces a twitch of muscle on the ipsilateral side
What is Trousseau sign in hypocalcaemia?
Carpopedal spasm when BP cuff is inflated + held for 3mins
What are the main causes of hypocalcaemia?
Hypoparathyroidism
Vitamin D deficiency
Chronic renal failure
List causes of hypoparathyroidism
Congenital (DiGeorge syndrome)
Trauma/iatrogenic
Autoimmunity
Low magnesium
What would levels of calcium, phosphate, PTH and ALP be like in hypoparathyroidism?
Calcium low
Phosphate high
PTH low
ALP normal
Which disease(s) are extreme manifestations of vitamin D deficiency?
Osteomalacia (adults)
Rickets (children)
What would levels of calcium, phosphate, PTH and ALP be like in osteomalacia?
Calcium normal/low
Phosphate low
PTH normal
ALP high
Outline treatment for (chronic) vitamin D deficiency
Vitamin D3 tablets
Calcitriol
Alfacalcidol
What is pseudo-hypoparathyroidism?
Resistance to PTH, causing hypocalcaemia (even though PTH may very well be high)
Which gene is defect in pseudo-hypoparathyroidism?
GNAS1 (causing dysfunction of G-protein)
What (the fck) is pseudo-pseudo-hypoparathyroidism?
Phenotypically the individual has pseudo-hypoparathyroidism, but biochemical aspects are normal (i.e. normal calcium)
Outline treatment of hypocalcaemia
IV calcium gluconate (acute)
Calcium supplements
Vitamin D supplements
What are calcium, PTH, ALP and phosphate levels like in hyperparathyroidism?
Calcium high
PTH high
ALP normal/high
Phosphate normal
What are calcium, PTH, ALP and phosphate levels like in bone malignancy?
Calcium high
PTH low
ALP high
Phosphate normal
What are calcium, PTH, ALP and phosphate levels like in FHH?
Calcium high
PTH normal/high
ALP normal
Phosphate high
What are calcium, PTH, ALP and phosphate levels like in hypoparathyroidism?
Calcium low
PTH low
ALP normal
Phosphate normal/high
