Asthma

Question 1

Pathophysiologic abnormality of asthma

Answer 1

Airway hyperresponsiveness

Question 2

Major risk factor for asthma

Answer 2

Atopy

Question 3

Seen in 80% of asthmatic patients

Answer 3

Allergic rhinitis

Question 4

Sensitizing allergens

Answer 4

Proteins with protease activity

Question 5

Independent risk factor for women with asthma

Answer 5

Obesity

Question 6

Late-onset asthma with concomitant nasal polyps

Answer 6

Intrinsic asthma

Question 7

Activated by inhaled allergens that release inflammatory mediators

Answer 7

IgE in mast cells

Question 8

MCC of perennial allergens

Answer 8

Dermatophagoides
Animal dander proteins
Cockroaches

Question 9

MCC of seasonal allergens

Answer 9

Grass pollen
Ragweed
Tree pollen
Fungal spores

Question 10

MC trigger of acute severe exacerbations

Answer 10

Viral URTI

Question 11

Common trigger of asthma particularly in children

Answer 11

Exercise

Question 12

Mechanism of EIA

Answer 12

Hyperventilation leading to increased osmolality of airway fluids

ABG: respi acid

Question 13

Prevention of EIA

Answer 13

B2 agonists and antileukotrienes prior to exercise

Best prevention: regular treatment with ICS

Question 14

Recommended for patients with aspirin-induced asthma

Answer 14

Salicylate-free diet

Question 15

2 types of asthma

Answer 15

Allergic asthma

Idiosyncratic/Intrinsic

Question 16

Allergic Asthma

Answer 16

(+) personal and/or family hx of allergic diseases

(+) wheal and flare skin reactions to ID injections

Inc level of serum IgE

(+) Response to provocation test

Question 17

Intrinsic Asthma

Answer 17

Adult-onset, non atopic, MORE SEVERE and persistent

(-) Personal and/or Fam Hx of allergy

(-) skin tests

(+) Nasal polyps

(+) Aspirin-sensitivity

N serum IgE but may have Inc IgE in airways due to staph enterotoxins

Question 18

Characteristic histo finding

Answer 18

Thickening of the BM due to subepithelial collagen deposition

Question 19

Pathology of asthma

Answer 19

Uniform regardless of type, changes do not extend to the lung parenchyma

Question 20

Characteristic of asthmatic airways

Answer 20

Eosinophil infiltration

Question 21

Phenotype predominant in asthmatics

Answer 21

TH2 (releases IL5 inc IgE formation)

Question 22

Major target cells of ICS

Answer 22

Epithelial cells

Question 23

Pro inflammatory cytokines associated with more severe disease

Answer 23

TNF a, IL 1B

Question 24

Mechanisms of AHR from epithelial damage

Answer 24

Loss of barrier function allowing penetration of allergens

Loss of enzymes degrading inflammatory mediators

Loss of relaxant factor

Exposure of sensory nerves

Question 25

Structural changes in the airways that may lead to irreversible narrowing

Answer 25

Inc airway smooth muscle Fibrosis Angiogenesis Mucus Hyperplasia

Question 26

Confirms airflow limitation in asthma

Answer 26

Spirometry | Decreased FEV1, FEV1/FVC, PEF

Question 27

Reversibility of spirometry in asthma

Answer 27

>12% and 200mL INCREASE in FEV1 15 mins after and inhaled short-acting B2-agonist (in some, 2-4 week trial of pred or prednisolone 30-40mg daily)

Question 28

Test for airway responsiveness

Answer 28

AHR: induced by methacholine or histamine challenge calculating the provocative concentration that reduces FEV1 by 20% (PC20)

Question 29

Three classes of bronchodilators

Answer 29

B2-adrenergic agonists Anticholinergics Theophylline

Question 30

MOA of bronchodilators

Answer 30

Reverse bronchoconstriction, relaxation of airway smooth muscle

Question 31

Most effective bronchodilators

Answer 31

B2 agonists

Question 32

Duration of action of SABAs | Albuterol, Terbutaline

Answer 32

3-6 hours | As PRN meds

Question 33

Duration of LABAs | Salmeterol, Formoterol

Answer 33

Over 12 hours, given BID | *never given in the absence of ICS

Question 34

MC AE of B2 agonists

Answer 34

Muscle tremor and palpitations

Question 35

Prevent cholinergic nerve-induced bronchoconstriction and mucus secretion

Answer 35

Anti-cholinergics (ipratropium, tiptropium) *used only as add-on bronchodilators not controlled by LABA + ICS

Question 36

MC reason for refractory asthma

Answer 36

Noncompliance