Endocrinology- Hypocalcaemia

Question 1

At what concentration of serum calcium does Symptomatic hypocalcaemia occur?

Answer 1

< 1.9 mmol/L

Question 2

What is the most common cause of hypocalcaemia?

Answer 2

Post-surgical hypoparathyroidism following thyroidectomy

Question 3

What are the 3 main causes of hypocalcaemia?

Answer 3

Post- surgical hypoparathyroidism Vitamin D deficiency Hypomagnesaemia

Question 4

What can cause Post-surgical hypoparathyroidism to be permanent?

Answer 4

Damage or inadvertent removal of parathyroid glands

Question 5

What is typical of phosphate levels with Vitamin D deficiency?

Answer 5

Low- Due to elevated PTH levels

Question 6

What type of hypoparathyroidism does hypomagnesaemia cause? What is typical of the PTH levels?

Answer 6

Functional hypoparathyroidism with normal or low PTH levels.

Question 7

What are the most common causes of low magnesium?

Answer 7

Gastrointestinal loss, alcohol and drugs, mainly proton pump inhibitors

Question 8

What are the clinical features of Acute severe hypocalcaemia?

Answer 8

Laryngospasm- Remember me u cheeky lil monkey Prolonged QT interval and seizures

Question 9

What are the 4 more common less acute features of hypocalcaemia?

Answer 9

Muscle cramps Carno-pedal spasm Peri-oral and peripheral paraesthesia Neuro-psychiatric symptoms

Question 10

What is a Chvostek’s sign?

Answer 10

Facial spasm when the cheek is tapped gently with the finger

Question 11

What is a Trousseau’s sign?

Answer 11

Carno-pedal spasm induced after inflation of a sphygmomanometer

Question 12

How is acute hypocalcaemia treated?

Answer 12

Immediate replacement treatment with intravenous calcium

Question 13

How is severe vitamin D deficiency treated?

Answer 13

Cholecalciferol. 20000 IU per week for 7 weeks followed by maintenance dose of 1-2000 IU per week

Question 14

How is hypoparathyroidism treated?

Answer 14

1-alfacalcidol or calcitriol.

Question 15

What dose of 1-alfacalcidol is given?

Answer 15

0.25mcg/day. Dose titration according to clinical and biochemical response.

Question 16

What calcium supplements are given in combination with 1-alfacalcidol?

Answer 16

Sandocal and Adcal D3

Question 17

Why is it important to keep calcium levels at the lower end of the reference range during replacement?

Answer 17

To avoid nephro-calcinosis

Question 18

What are the treatments for magnesium deficiency?

Answer 18

In acute case- Intravenous magnesium replacement If caused by GI loss or alcohol- Specialist input to prevent recurrence

Question 19

What causes Pseudo-hypoparathyroidism?

Answer 19

Mutation in a G protein coupled to the PTH receptor which leads to PTH resistance.

Question 20

What evidence is there to suggest PTH resistance and not deficiency?

Answer 20

Hypocalcaemia, but with High PTH and normal vitamin D levels

Question 21

What 4 physical characteristics do patients with Pseudo-hypoparathyroidism exhibit?

Answer 21

Syndromic appearance Short stature Round face Short 4th and 5th metacarpals