Asthma and allergy
Download
1 / 33

Asthma and Allergy - PowerPoint PPT Presentation


  • 84 Views
  • Uploaded on

Asthma and Allergy. Atopy v Allergy Asthma Aeroallergens – indoor & outdoor Occupational allergens. Atopy. The propensity to produce IgE to allergens Demonstrated using Skin prick tests to common inhalant allergens. Allergen-Antibody interaction. Prick Test Reagents. Skin Prick Tests.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Asthma and Allergy' - kizzy


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
Asthma and allergy
Asthma and Allergy

  • Atopy v Allergy

  • Asthma

  • Aeroallergens – indoor & outdoor

  • Occupational allergens


Atopy
Atopy

  • The propensity to produce IgE to allergens

  • Demonstrated using Skin prick tests to common inhalant allergens





Allergy
Allergy

  • IgE mediated inflammatory tissue damage in response to an allergen causing clinical disease


Asthma epidemiology
Asthma - epidemiology

  • X 2- 3 increase last 30 years

  • Concomitant similar increase in atopy, hayfever and eczema

  • ? Environmental Change

  • ? Less infections ( hygiene hypothesis )


Allergens
Allergens

  • Outdoor

  • Pollens-

    • Tree

    • Grass

  • Moulds-

    • Alternaria

    • Aspergillus

    • Cladosporium

    • Penicillium


Allergens1
Allergens

  • Indoor

    • Cat

    • Dog

    • Cockroach

    • Birds


Inhalation of allergen
Inhalation of allergen

  • Immediate response ( IgE mediated )

    • Max: 20 min.

    • Ends : 60 min.

  • Late response in 50% (Eosinophil )

    • Onset 3h

    • Max 12 h

    • End 24 h

  • Responsible for airways hyperreactivity

  • Allergen ID and avoidance therefore very important



Allergic history and negative skin tests
Allergic history and negative skin tests

  • Remember grass pollen allergy


Pollenosis
Pollenosis

  • Prof. Paul Potter, Cape Town

  • Big role for grass pollens in respiratory allergy

  • Kikuyu grass

  • Bermuda grass

  • Buffalo grass ( l’herbe bourrique )

  • SPT regents to detect allergy to these being developed

  • Mauritus has all of these grasses in abundance


Why study pollens
Why study pollens

  • Potential for immunotherapy


Indoor allergens avoidance
Indoor allergens-avoidance

  • House dust mite allergen

    • Large

    • Not easily air-borne

    • Needs close proximity to bedding to be inhaled


House dust mite avoidance
House dust mite avoidance

  • Mite impermeable mattress covers

  • Hot wash bedding linen ( 55 C )

  • Remove moquettes

  • Light curtains

  • Vacuum clean with high filtration cleaner




Pet allergens
Pet allergens

  • Remove the pet

  • Clean it

  • Remove carpets ( x 100 fold antigen)



Asthma none of usual aeroallergens
Asthma- none of usual aeroallergens

Think of occupational asthma


Occupational asthma
Occupational Asthma

  • Asthma initiatedby an agent inhaled at work

  • Cf. Work-related asthma

    • Pre-existing asthma provoked by an irritant in the workplace


Occupational asthma1
Occupational asthma

  • Only a % of workers affected

  • Latent period before onset ( 2 Yr.)

  • Improvement during periods away from work

  • Once established can be triggered by really small doses of antigen


Usual suspects

HMW ( Biologic )

Latex

Flour ( 334 )

Laboratory mammals(188)

Bacillus subtilis

LMW ( haptens )

Colophony ( 175 )

Wood dust

Diisocyanates ( 658 )

Platinum salts

Acid anhydrides ( 364 )

Glutaraldehyde

Plastics workers

Bone cement

Usual suspects








Occupational asthma4
Occupational asthma

  • Diagnosis will have major impact on patient’s life

  • False + ve : needless loss of job

  • False – ve : Needless continuing exposure

  • Be careful


Thank you
Thank You

  • Discussion


ad