Asthma questions

Question 1

Definition

Answer 1

Asthma is a chronic inflammatory airway disease characterized by reversible, intermittent airway obstruction and hyper-reactivity involving multiple cellular pathways such as mast cells and eosinophils.

Question 2

Pathophysiology

Answer 2

Airway inflammation and hyper-responsiveness driven by T-helper type 2 cells (Th2), with production of IL-4, IL-5, and IL-13. This results in mucus hypersecretion, airway remodeling, and bronchoconstriction.

Question 3

Epidemiology

Answer 3

Global prevalence is 262 million cases in 2019. High prevalence in Australia and Sweden; low prevalence in China and Vietnam. In the UK, 5.4 million people have asthma.

Question 4

History

Answer 4

Recurrent episodes of wheezing, shortness of breath, chest tightness, or cough. Symptoms worsen with triggers like allergens, cold air, or infections. Smoking and family history are key contributors.

Question 5

Examination

Answer 5

Polyphonic wheeze audible on expiration, signs of atopy (eczema or rhinitis). Severe cases may present with silent chest or accessory muscle use.

Question 6

Investigations - Bedside

Answer 6

Spirometry is the diagnostic gold standard, showing FEV1/FVC ratio <0.7. Peak expiratory flow (PEF) used for variability assessment over 2–4 weeks.

Question 7

Investigations - Bloods

Answer 7

Blood eosinophil counts may indicate corticosteroid responsiveness. Fractional exhaled nitric oxide (FeNO) levels >40 ppb suggest eosinophilic inflammation.

Question 8

Investigations - Imaging

Answer 8

Chest X-rays are normal in most cases but used to exclude other conditions like pneumothorax. High-resolution CT helps in identifying complications.

Question 9

Investigations - Special Tests

Answer 9

Bronchial challenge tests (methacholine or histamine) confirm airway hyper-reactivity. Allergy testing identifies environmental triggers.

Question 10

Management - Conservative

Answer 10

Smoking cessation, allergen avoidance, and patient education. Encourage influenza and pneumococcal vaccinations.

Question 11

Management - Medical

Answer 11

Stepwise approach includes short-acting beta-agonists (SABAs), inhaled corticosteroids (ICS), long-acting beta-agonists (LABAs), and biologics like anti-IL-5 therapies.

Question 12

Management - Surgical

Answer 12

Bronchial thermoplasty for severe, refractory cases. No routine surgical management.

Question 13

Risks of Treatments

Answer 13

ICS may cause oral thrush; long-term use increases pneumonia risk. Biologics carry risks of hypersensitivity reactions.

Question 14

Benefits of Treatments

Answer 14

Improves quality of life, reduces symptoms, and prevents exacerbations. Early intervention prevents disease progression.

Question 15

Medical and Laboratory Sciences

Answer 15

FeNO testing identifies eosinophilic phenotypes. Spirometry aids in monitoring lung function.

Question 16

Prognosis

Answer 16

Good prognosis with appropriate management. Severe asthma has a higher risk of permanent airway remodeling.

Question 17

Complications

Answer 17

Complications include status asthmaticus, respiratory failure, and chronic airflow limitation. Increased susceptibility to infections.

Question 18

Differentials

Answer 18

COPD, vocal cord dysfunction, bronchiectasis, congestive heart failure, and pulmonary embolism. Differentiation relies on history, spirometry, and imaging.

Question 19

Cheat Sheet/Buzz Words

Answer 19

Buzzwords: Polyphonic wheeze, diurnal variation, FeNO, SABA, LABA, ICS, biologics, airway hyper-responsiveness.