Asthma

Question 1

What are obstructive airway diseases?

Answer 1

Diseases that affect the airways

Question 2

What is the triad of asthma?

Answer 2

1. Airway hyper responsiveness
2. Airway inflammation
3. Reversible obstruction

Question 3

What is the end result of asthma on the airways?

Answer 3

Airway remodelling.

Question 4

What are the three hallmarks of airway remodelling

Answer 4

1. Basement membrane thickens
2. collagen deposition on Sub mucosa
3. Smooth muscle hypertrophy

Question 5

Summarise the pathogenesis of asthma (steps) (4)

Answer 5

1. Genetic predisposition/ Triggers
2. Eosinophilic inflammation
3. TH2 cytokines and mediators
4. Twitchy smooth muscle

Question 6

Common allergens for asthma?

Answer 6

• Animal dander
• dust mites
• pollen
• fungi

Question 7

Are symptoms and signs of asthma episodic/non?

Answer 7

Episodic

Question 8

What kind of cough does asthma produce

Answer 8

Non productive. Can have wheeze tho

Question 9

Does the asthma get worse at specific times?

Answer 9

Diurnal variablility

Question 10

What other diseases can asthma be linked to?

Answer 10

Allergic triad

Question 11

Can asthma be dependent on family history

Answer 11

Yes, common to have asthmatics in the family

Question 12

What findings can confirm asthma?

Answer 12

• history/ exam
• Diurnal variability of PEFR
• Reduced FEV1/FEV <75%
• response to salbutamol >15%
• Provocation test: bronchospasm

Question 13

How would you treat an acute presentation of asthma?

Answer 13

1. Oral steroid- Prednisolone

2. B2 agonist- NEBULISED salbutamol.

Question 14

What are the treatment steps for chronic asthma? (4)

Answer 14

1. SABA
2. Inhaled steroid
3. Add LABA/LAMA
4. Anti IgE, Anti IL5, Leukotriene antagonists, theophylline, Cromone

Question 15

Example of SABA?

Answer 15

Salbutamol/ terbutaline

Question 16

Example of LABA?

Answer 16

Salmeterol/ formoterol

Question 17

What is the action mechanism for SABA’S/LABA’S? (Refer to the specific molecular pathway)

Answer 17

• B2 Agonist joins to adenylyl cyclase
• AC produces CAMP
• CAMP= Reduces Ca conc
• CAMP= stimulates PKA
• PKA= inactivates MLCK, Activates MLCphosphatase
• Relaxation

Question 18

End result of B2 agonists?

Answer 18

• Relaxes smooth muscle

- Dilates bronchial airways

Question 19

What are the common combination therapies used of B2 agonists in Asthma? Eg?

Answer 19

LABA/LAMA + ICS

Eg- Formoterol + beclamethasone

Question 20

Example of an inhaled steroid used in asthma?

Answer 20

Beclomethasone

Question 21

Why is a spacer device useful?

Answer 21

• Avoids systemic effects
• Good lung deposition
• Lowers oropharyngeal and laryngeal side effects
• Avoids coordination problems

Question 22

What are the actions of Cromones?

Answer 22

Anti inflammatory- Mast cell Stabilisers

Prevent histamine release.

Question 23

Example of Cromone?

Answer 23

Cromoglycate

Question 24

How do Leukotriene antagonists work?

Answer 24

Competitively block CysLT1 receptor.

Receptor to LTC4, LTD4 & LTE4 which cause smooth muscle contraction, mucus secretion and oedema

Question 25

Example of leukotriene antagonist?

Answer 25

Montelukast. Admin- ORAL

Question 26

Action mechanism for Anti IgE therapeutics?

Answer 26

Inhibits IgE receptor preventing mediator (histamine) release from basophils and mast cells.

Question 27

Example of an anti IgE?

Answer 27

Omalizumab. Injections once 2-4 weeks

Question 28

Action mechanism for Anti Il-5?

Answer 28

Blocks TH2 cytokine IL-5 receptor which causes eosinophilic inflammation. Injection- 1nce 4 weeks

Question 29

What are the effects of M1 ,M2 and M3 cholinergic receptors?

Answer 29

M1- Enhance cholinergic reflex M2- Inhibit Ach release M3- Cause bronchoconstriction + mucus secretion

Question 30

What are the main effects of anti cholinergics?

Answer 30

Block M3 receptor- prevents broncho-constriction and mucus secretion

Question 31

Example of SAMA and LAMA?

Answer 31

SAMA- Ipratropium | LAMA- Tiotropium

Question 32

What is an example of a methylxanthine?

Answer 32

Theophylline

Question 33

Action mechanism for theophylline?

Answer 33

Inhibits PDE enzyme, enhancing action of CAMP | Result- increased smooth muscle relaxation