II. Epidemiology
- Much more common in children than adults
- Age Onset under 40 years old
III. Pathophysiology
- IgE mediated response to allergens
- Immediate Allergic Reaction
- Late-phase Allergic Reaction
IV. Types: T2 High Phenotypes
- Early Onset Allergic Asthma (Atopic Asthma)
- Classic Asthma presentation, allergic sensitization and steroid responsiveness
- Late Onset Eosinophilic Asthma
- Often steroid refractory, and typically severe from onset with frequent exacerbations
- Associated with Staphylococcus AureusEnterotoxins
-
Aspirin Exacerbated Respiratory Disease (Samter's Triad)
- Associated with disordered Arachidonic Acid metabolism (cyclooxygenase mediated to inflammatory agents)
- Typically severe from onset with frequent exacerbations
- Associated with increased urinary LTE4 > 166 pg/mgCr
V. Causes: Triggers
- Indoor allergens (perennial allergens)
- Outdoor allergens (seasonal allergens)
- Tree, grass or weed pollens
- Mold Spores
-
Aspirin Exacerbated Respiratory Disease (Samter's Triad)
- Aspirin or NSAID sensitivity
- Nasal Polyps
- Asthma
VI. Findings: Symptoms and Signs
VII. Labs: Markers
-
Eosinophilia
- Induced Sputum with >3% Eosinophils
- Complete Blood Count with increased Eosinophils
- Fractional Excretion of Nitric Oxide (FeNO)
- FeNO > 50 ppb in adults (>35 ppb in children) is associated with Eosinophilic airway inflammation
- Positive values are associated with steroid responsiveness
- Serum Total IgE
-
Serum Periostin
- Elevated in Type 2, Eosinophilic Asthma
VIII. Management
- See Environmental Allergen
- See Asthma Management
- See Asthma Exacerbation
- Consider Immunotherapy for those with persistent Allergic Rhinitis and Asthma
- Allergic, refractory Severe Asthma may be treated with Biologic Agents
Images: Related links to external sites (from Bing)
Related Studies
| Concepts | Disease or Syndrome (T047) |
| ICD9 | 493.0 |
| ICD10 | J45 |
| SnomedCT | 195968006, 16862005, 389146007, 233680000, 195972005, 266358007, 266396008, 155575009, 389145006 |
| French | ASTHME, Asthme atopique, Asthme extrinsèque, Asthme allergique |
| English | Extrinsic asthma, Extrinsic asthma NOS, Allergic asthma, ASTHMA EXTRINSIC, extrinsic asthma, extrinsic asthma (diagnosis), Asthma extrinsic, asthma atopic, asthma extrinsic, allergic asthma, atopic asthma, extrinsic allergic asthma, Extrinsic asthma (disorder), Extrinsic asthma NOS (disorder), Allergic atopic asthma (disorder), asthma allergic, Allergic asthma (diagnosis), Atopic asthma, Allergic atopic asthma, Allergic asthma (disorder), asthma; allergic extrinsic, asthma; atopic, asthma; extrinsic, atopic; asthma, extrinsic; asthma, allergic; asthma, extrinsic, allergic; extrinsic asthma, Extrinsic asthma [Ambiguous] (disorder), Allergic atopic asthma [Ambiguous], Asthma, atopic, Asthma, allergic NOS |
| Dutch | atopisch astma, extrinsiek astma, allergisch astma, allergisch; astma, extrinsiek, allergisch; extrinsiek astma, astma; allergisch extrinsiek, astma; atopisch, astma; extrinsiek, atopisch; astma, extrinsiek; astma |
| German | Asthma extrinsisch, extrinsisches Asthma, allergisches Asthma, atopisches Asthma, ASTHMA EXTRINSISCH |
| Italian | Asma estrinseca, Asma allergica, Asma atopico |
| Portuguese | Asma alérgica, Asma extrínseca, Asma atópica, ASMA EXTRINSECA |
| Spanish | Asma atópica, Asma alérgica, Asma extrínseca, asma extrínseco, asma extrínseco (trastorno), asma extrínseco, SAI (trastorno), asma extrínseco, SAI, asma extrínseca, SAI, asma atópica, asma extrínseca (trastorno), asma extrínseca, asma extrínseca, SAI (trastorno), asma alérgica (trastorno), asma alérgica |
| Japanese | 外因性喘息, アトピー性喘息, アレルギー性喘息, ｱﾚﾙｷﾞｰｾｲｾﾞﾝｿｸ, ｶﾞｲｲﾝｾｲｾﾞﾝｿｸ, ｱﾄﾋﾟｰｾｲｾﾞﾝｿｸ |
| Czech | Exogenní astma, Alergické astma, Atopické astma |
| Hungarian | Extrinsic asthma, Atopiás asthma, Allergiás asthma |
