Send the link below via email or IMCopy
Present to your audienceStart remote presentation
- Invited audience members will follow you as you navigate and present
- People invited to a presentation do not need a Prezi account
- This link expires 10 minutes after you close the presentation
- A maximum of 30 users can follow your presentation
- Learn more about this feature in our knowledge base article
Transcript of Hypersensitivity
Body reacts with exaggerated immune response to what is perceived as foreign substance.
Antigen – Antibody reaction
But, how does an
Types of Hypersensitivity
is a substance often harmless that a body recognize as a pathogen or a harmful invader which evokes immune responses (fever, inflammations, rash… etc)
IgE on the surface of mast cell causes degranulation of the mast cell releasing chemicals as Histamine therefore resulting in allergic responses like inflammation and swelling
Stimulates B cells to
Eating something you are allergic to can cause nausea and vomiting
Skin rash, hives, itching, blisters, or skin peeling.
Stuffy nose, itchy nose and throat, and cough
Eyes may cause itchy, watery, red, swollen eyes
Type I Hypersensitivity
Common Allergens for type 1 Hypersensitivity
Drugs as Penicillin
histamine and other inflammatory
mediators are produced.
What's significant about them?
Performed in granules
Prostaglandins and leukotrienes
Formed after activation
within 30 mins
Mast cells control immediate response
Neutrophilis and esnophilis control late or chronic response
Treatment for type 1
Immunotherapy by desensitization
Antihistamines as diphenhydramine (Bendaryl) - blocks histamine receptors
Epinephrine -prolongs or increases cAMP levels in mast cells which inhibits degranulation.
Non-steroidal anti-inflammatory drugs
There's a difference between a localized allergen reaction and a true
anapylactic shock !
is a severe, life threatening
whole-body allergic reaction
to a chemical that has become an allergen. Anaphylaxis happens quickly after second exposure.
Within minutes of exposure an to an allergen anaphylatic reaction occurs
Constriction of airways making it difficult to breath
Dilation of blood vessels causing a systemic drop in blood pressure
How to save a life?
Adrenaline auto-injectors (Epipens) are prescribed for those believed to be at risk
If all these things happen together and you don't respond
How to test for Anaphylaxis?
Another example of type 2 hypersensitivity is Erythroblastosis fetalis
It's caused when an RH- mother carries an RH+ fetus, and effect of treatment with anti-Rh antibody, or Rhogam
What are the signs and symptoms of erythroblastosis fetalis ?
Type II hypersensitivity
(or cytotoxic hypersensitivity)
What happened to the patient?
Well, this is called Serum sickness and it's an example of
Type III hypersensitivity
Signs and symptoms
of Serum sickness
Corticosteroid creams or ointments
After treatment, the symptoms usually go away within a few days.
We're not done yet
Last but not least ...
Type IV Hypersensitivity
Referred to as delayed because it takes a few days to develop.
It involves Th1 cells attracting and activating macrophages
Yara El Messiry
Chemotherapy drugs (hapten)
Drug Induced Cyctotoxic reactions
It's not only antiserum which causes Serum sickness
Serum sickness likes reactions
It has similar symptoms to serum sickness, but in which immune complexes are not found
In severe cases
There are 1 in 5 people who suffer from hypersensitivity in the US