Biochemical Tests 1: Calcium

Question 1

What is Calcium? (1)

Answer 1

Essential nutrient for healthy bones.

Question 2

How are calcium levels regulated? (3)

Answer 2

Parathyroid Hormone
Vitamin D3
Calcitonin

Question 3

What is the reference range for Calcium? (1)

Answer 3

2.2-2.6 mmol/L

Question 4

What is hypercalcaemia? (1)

Answer 4

Raised levels (>2.6 mmol/L)

Question 5

What calcium level indicates medical attention? (1)

Answer 5

> 3.75mmol/L = MI risk

Question 6

What factors may cause hypercalcaemia? (7)

Answer 6

Malignancy
Primary Hyperparathyroidism
Drugs
Hyperthyroidism
Renal disease
Non-parathyroid endocrine diseases
Dehydration

Question 7

What are the s/s of hypercalcaemia? (6)

Answer 7

Bone pain
Abdominal pain / Arrhythmias
Cardiac arrest
Kidney stones

Muscle weakness
Excessive Urination

Question 8

What is the reference range for mild hypercalcaemia? (1)

Answer 8

2.6-3.0mmol/L

Question 9

What is the reference range for moderate hypercalcaemia? (1)

Answer 9

3.01-3.4mmol/L

Question 10

What is the reference range for severe hypercalcaemia? (1)

Answer 10

> 3.4mmol/L

Question 11

What are the specific symptoms for mild hypercalcaemia? (1)

Answer 11

Asymptomatic

Question 12

What are the non-specific symptoms for moderate hypercalcaemia? (11)

Answer 12

N+V
Headache
Confusion
Drowsiness
Constipation
Flank Pain
Depression
Weakness
Polyuria
Nocturia

Question 13

What are the specific symptoms for severe hypercalcaemia? (1)

Answer 13

Symptoms as moderate hypercalcaemia but can progress to coma.

Question 14

Explain the general management of hypercalcaemia. (1)

Answer 14

Dependent on underlying cause.

Question 15

What investigations should be carried out in suspected hypercalcaemia? (10)

Answer 15

Severity
Calcium levels
Hydration status
PTH
U+E’s
Vitamin D
Mg + Phosphate
Relevant diagnostic tests/ referrals
Review current medications

Question 16

Give e.g. of drugs that cause hypercalcaemia. (6)

Answer 16

Thiazide diuretics
Lithium
Calcium supplements
Vitamin D supplements
Vitamin A supplements
Antacids + calcium salts

Question 17

Explain the management of mild to moderate hypercalcaemia. (2)

Answer 17

Hydration
IV bisphosphonates if not responding adequately.

Question 18

Explain the management of severe/known malignancy hypercalcaemia. (2)

Answer 18

Hydration
IV Bisphosphonates (pamidronate/zolendronate)

Question 19

What factors can cause hypocalcaemia? (6)

Answer 19

Renal Failure
Raised phosphate levels (as phosphate binds to calcium readily)
Hypoparathyroidism
Low Mg levels
Deficiency
Malabsorption

Question 20

What is the reference range of mild hypocalcaemia? (1)

Answer 20

1.9-2.2mmol/L

Question 21

What is the reference range of severe hypocalcaemia? (1)

Answer 21

< 1.9mmol/L

Question 22

What are the s/s of acute hypocalcaemia? (12)

Answer 22

Syncope
Congestive Heart Failure
Numbness
Tingling
Muscle Spasms
Tetany
Wheeze
Dysphagia
Irritability
Depression Fatigue
Seizures

Question 23

What are the s/s of chronic hypocalcaemia? (6)

Answer 23

Coarse Hair
Brittle Nails
Psoriasis
Dry Skin
Pruritic
Poor Dentition

Question 24

Give e.g. of medications that cause hypocalcaemia. (4)

Answer 24

Bisphosphonates
Denosumab
Anticonvulsant
Cinacalcet

Question 25

Explain the management of hypocalcaemia. (5)

Answer 25

Check magnesium
Baseline PTH and vitamin D levels.
Identify underlying cause.

Supplements:
Mild: Oral prep (between 400-2000mg of calcium). Titrate accordingly.
Severe (1.9): IV calcium glauconite. Switch to oral ASAP.