Hypocalcaemia and Hypoparathyroidism

Question 1

what are the symptoms associated with hypocalcaemia

Answer 1

paraesthesia(fingers, toes, perioral), muscle cramps, tetany, muscle weakness, fatigue, fits

Question 2

what are the signs associated with hypocalcaemia

Answer 2

bronchospasm or laryngospasm, Chovsteks sign(tapping over facial nerve), Trousseau sign(carpopedal spasm)

Question 3

what treatment is given for acute hypocalcaemia

Answer 3

IV calcium gluconate 10ml

Question 4

how can activity of the parathyroid gland affect calcium homeostasis

Answer 4

hypoparathyroidism causes hypocalcaemia

hyperparathyroidism causes hypercalcaemia

Question 5

what are the different causes of hypoparathyroidism

Answer 5

congenital(DiGeorge syndrome), destruction, autoimmune, hypomagnesaemia, idiopathic

Question 6

what are some of the ways in which parathyroid destruction can occur

Answer 6

surgery, malignancy, raadiotherapy

Question 7

what is the long-term management for hypocalcaemia

Answer 7

calcium supplement >1-2g per day and Vitamin D tablets

Question 8

describe how hypomagnesaemia can cause hypocalcaemia

Answer 8

Ca release from cells is dependant on Mg, so in hypomagnesaemia intracellular Ca high, PTH release inhibited, and skeletal and muscle receptors less sensitive to PTH

Question 9

what treatment is give for hypomagnesaemia with hypercalcaemia

Answer 9

supplement replacement of both

Question 10

what are some of the causes of hypomagnesaemia

Answer 10

alcohol, drugs, GI illness, pancreatitis, malabsorption

Question 11

describe what pseudohypoparathyroidism is

Answer 11

genetic defect, low Ca, but elevated PTH, due to PTH resistance

Question 12

what clinical features are seen with pseudohypoparathyroidism

Answer 12

bone abnormalities, subcutaneous calcification, learning disability, brachdactyly(shortened 4th metacarpal)

Question 13

what is pseudo-pseudohypoparathyroidism

Answer 13

when bone abnormalities are present(eg Albright’s hereditary osteodystrophy, but no alteration in PTH action so normal Ca

Question 14

what is the active form of vitamin D and where is it formed

Answer 14

1,25dihydroxy vitamin D, formed in kidney

dietary is vitamin D3

Question 15

what 2 conditions are caused by vitamin deficiency

Answer 15

rickets in children

osteomalacia in adults

Question 16

what are the different causes of vitamin D deficiency

Answer 16

dietary deficiency, malabsorption, chronic renal failure, lack of sunlight, drugs

Question 17

what are the clinical features of osteomalacia

Answer 17

low Ca, muscle wasting, dental defects, bone; tenderness, fractures, deformities, looser zones

Question 18

why does chronic renal failure lead to vitamin D deficiency

Answer 18

because you are unable to convert vitamin D into active form 1,25dihydroxy vitamin D
(can also result in secondary hyperparathyroidism)

Question 19

what long-term treatment is used for vitamin D deficiency

Answer 19

vitamin D3 tablets, or combined calcium and vitamin D3 if hypoclcaemia

Question 20

describe the biochemistry seen in hypoclacaemia

Answer 20

low Ca, low PTH, normal ALP, high/normal phosphate

Question 21

describe the biochemistry seen in osteomalacia

Answer 21

low Ca, raised PTH, high ALP, low phosphate