Corticosteroids

Question 1

How to recognize corticosteroids?

Answer 1

Anything ending in -one

Question 2

List the endogenous corticosteroids

Answer 2

• Cortisone (glucocorticoid)

- Aldosterone (mineralocorticoid)

Question 3

Relative strength of corticosteroids:

Answer 3

• Hydrocortisone: anti-inflammatory = 1, salt/water retention = 1
• Prednisone: anti-inflammatory = 4, salt/water retention = 0.8
• Betamethasone: anti-inflammatory = 27, salt/water retention = none,
• Dexamethasone: anti-inflammatory = 27, minimal salt/water retention
• Anti-inflammatory potency: Betamethasone/dexamethasone» Prednisone > Hydrocortisone.
• Water retency potency: Hydrocortisone > Prednisone > Dexamethasone > Betamethasone

Question 4

Describe the mechanisms of anti-inflammatory activity of corticosteroids

Answer 4

Mode of anti-inflammatory action of glucocorticoids:

• Glucocorticoid cross plasma membrane
• Bind with glucocorticoid receptor (GCR) in cytosol
• Glucocorticoid + GCR complex enter nucleus and bind with nucleus at glucocorticoid response element
• Genetic response:
  1) Transactivation: anti-inflammatory proteins are transcribed and translated
  2) Transpression: inflammatory genes are switched off
  3) Post genomic effects: pro-inflammatory mRNA is destabilized
  4) Activation of histone deacetylases: winding of DNA to prevent inflammatory mRNA transcription

Question 5

Function of mineralocorticoids

Answer 5

Aid in salt and water retention (i.e. electrolyte balance)

Question 6

Function of glucocorticoids

Answer 6

Anti-inflammatory activity

Question 7

short term Side-effects of corticosteroid

Answer 7

• Weight gain
• increased blood glucose
• Mood changes - i.e. psychosis (most dangerous)
• Low potassium (hypokalaemia)
• Treatment: stopping drugs reverses effects

Question 8

Long-term cumulative effects of corticosteroid

Answer 8

Mineralocorticoids:

• water retention
• oedema
• weight gain

Glucocorticoids

• osteoporosis: lose 3% of bone density per year (opposed to 1%), reduced bone formation proteins (osteocalcin)
• Increased blood glucose
• Muscle wasting & thin skin
• Increased infection risk
• Increased cardiovascular risk

Question 9

Reduced calcium absorption and increased calcium excretion is a side-effect of corticosteroid

Answer 9

True

Question 10

Monitoring of corticosteroids:

Answer 10

Clinical:

• body weight
• height (children)
• Blood pressure

Laboratory

• blood sugar
• lipids

Question 11

Understand the mechanism and consequences of adrenal axis suppression and methods to minimise the risk in dental patients

Answer 11

Hypothalamic-pituitary adrenal (HPA) axis suppression:

• For the duration of steroid treatment, the patient’s endogenous steroid release has been suppressed.
• People don’t produce own steroids so need to slowly reduce prescription
• Give steroid with short half-lives so patient’s body can start producing own when dosage wears off.