2. ALLERGY
Yousra Imran
2011-ag-1053
M. Sc 3rd

3. Allergy
 Allergy is a specific immunological reaction to a
normally harmless substance, one that does not bother
most people. It is often characterized by redness of
the skin, warmth, swelling, and pain and
inflammation of respiratory track..

4. Allergen
 A substance capable of sensitizing the body in such a
way that an unusual response occurs, in
hypersensitive person

5. TYPES OF ALLERGEN
Allergens that cause allergic reactions include:
 Pollens
 House dust mites
 Mold spores
 Food
 Latex rubber
 Insect venom
 Medicines
 Fragrance

8. INTRODUCTION
 The term allergy was first defined in 1906 by von
Pirquet in describing a changed reaction in the
body. An unusual response of a person to a
substance that is harmless to others, the individual
is said to be allergic.
 500 million people suffer from food allergy
 300 million suffer from asthma
 Excessive cause of allergy is over-sanitation,
utilization of antibiotics & less exposure to viruses
and bacteria in childhood.
 Allergy involves an exaggerated response of the
immune system.

9. Immunology Of Allergy
• Elevated IgE levels seen in allergy and parasitic
infection.
• Binds to mast cells and basophils.
• Often specific for harmless environmental factors
– allergens.

11. Cont…..
 Immune system activated when pathogen
enters
 B-cells produce antibodies-immunoglobulin
 Five types of immunoglobulin in which IgE is important
in allergic reaction.
 Attached to mast cell at determine site-crosslinking

12. COMMON SYMPTOMS OF ALLERGY
AFFCTED ORGANS SYMPTOMS
Nose Swelling of nasal mucosa
Sinuses Allergic sinusitis
Eyes Redness and itching of conjunctiva.
Airways Sneezing, coughing, bronchoconstriction, wheezing,
dypsea and asthma.
Ear Feeling of fullness, possibly pain and impaired haring.
Skin Rashes such as eczema and hives
Gastrointestinal pain Abdominal pain, bloating, vomiting and diarrhea

14. Causes of Allergy
 Foods
 Non-food proteins
 Toxins interacting with proteins
 Airborne allergen
 Genetic basis

15. Mechanism of allergy
o Acute response
o Late-phase response

16. Acute response

18. Late-phase response

19. Allergic disorders
 Atopic dermatitis
 Allergic rhinitis
 Asthma
 Food allergy
 Anaphylaxis

20. The Allergic Disorders
Atopic dermatitis
(Eczema)
Nervous system:
Headaches
Gastrointestinal Irritability
symptoms
.
Muscle pain
Food Allergy
Allergic
Asthma rhinoconjunctivitis
(cough; (hay fever)
wheeze)
20 Anaphylaxis

21. Atopic dermatitis(Eczema)
 Chronic inflammatory skin disorder
 Affects at least 15% of children & up to 10% of adults
 Atopic dermatitis is often the first manifestation of
allergic disease & many patients may develop allergic
rhinitis and asthma later in life
 Symptoms:
rashes are dry, scaly and itchy
In infants & young children, the rashes appear on the
face, neck, cheeks and scalp
In older children & adults-appear on the folds of the
forearms, the inner elbows and behind the knees

22.  Factors that make the symptoms worse include
temperature, humidity, irritants, infections, food,
inhalant and contact allergens and emotional stress
 Treatment:
Topical corticosteroids , lifestyle changes & the use of
medications

23. Types of Eczematous Dermatitis
 Contact Eczema
 Seborrheic Eczema
 Nummular Eczema
 Neurodermatitis
 Stasis Dermatitis
 Dyshidrotic Eczema

24. Contact Eczema
 Contact eczema is a localized reaction that includes
redness, itching & burning in areas where the skin has
come into contact with an allergen
 Due to the vast number of substances with which
individuals have contact, it can be difficult to determine
the trigger for contact dermatitis.
 The condition is sometimes referred to as allergic
contact eczema , if the trigger is an allergen and irritant
contact eczema.
 People who have a history of allergies have an increased
risk for developing contact eczema.

26. Seborrheic Eczema
 Seborrheic eczema is a form of skin inflammation of
unknown cause.
 The signs and symptoms include yellowish, oily, scaly
patches of skin on the scalp, face & occasionally other
parts of the body. Dandruff and "cradle cap" in infants.
 It is common place for seborrheic dermatitis to inflame
the face at the creases of the cheeks and/or the nasal
folds.
 This condition tends to run in families. Emotional stress,
oily skin, infrequent shampooing, and weather
conditions are felt to be factors for developing seborrheic
eczema.
 One type of seborrheic eczema is also common in people
with AIDS.

28. Nummular Eczema
 Nummular eczema is characterized by coin-shaped
patches of irritated skin -- most commonly located on
the arms, back, buttocks, and lower legs -- that may be
crusted, scaling, and extremely itchy.
 occurs most frequently in elderly men and women.
 usually a chronic condition.
 A personal or family history of atopic dermatitis, asthma,
or allergies increases the risk of developing the
condition.

30. Neurodermatitis
 chronic skin inflammation caused by a scratch-itch cycle
that begins with a localized itch that becomes intensely
irritated when scratched.
 Women are commonly affected, frequent in people 20-
50 years of age.
 This form of eczema results in scaly patches of skin on
the head, lower legs, wrists, or forearms.
 Over time, the skin can become thickened and leathery.

32. Stasis Dermatitis
 skin irritation on the lower legs, generally related to the
circulatory problem known as venous insufficiency, in
which the function of the valves within the veins has
been compromised.
 exclusively in middle-aged and elderly people, with
approximately 6%-7% of the population over 50 years
of age being affected by the condition. The risk is higher
in advancing age.
 Symptoms include itching and/or reddish-brown
discoloration of the skin on one or both legs.
 ulcers may develop in affected areas.
 lead to an increase in fluid buildup (edema) in the legs.

34. Dyshidrotic Eczema
 irritation of the skin on the palms of hands & soles of the
feet characterized by clear, deep blisters that itch and
burn.
 Cause are unknown.
 also known as vesicular palm plantar dermatitis,
dyshidrosis, or pompholyx.
 occurs in up to 20% of people with hand eczema &
common during the spring & summer months & in
warmer climates.

36. Allergic rhinitis
 an IgE-mediated inflammation of the nasal mucosa in
response to outdoor and indoor allergens
 affects between 10 to 30 percent adults and more than
40% of children worldwide
 Causes:
pollens, dust mites, molds and insects
o Symptoms:
sneezing, runny or stuffy nose, teary eyes and itchy
nose, throat or skin

38. Classification of Allergic Rhinitis
 Based on frequency & severity of symptoms
mild intermittent
mild persistent
moderate/severe intermittent
moderate/severe persistent
 Based on type of allergen
perennial
seasonal

40. Asthma
 life-long inflammatory disease characterized by airway
hyper responsiveness & airflow obstruction
 the inner lining of the airways become inflamed and the
muscles surrounding the airways tighten up mucus
glands in the airways secrete thick mucus-cause the
airway to narrow - leads to difficult breathing, shortness
of breath, cough and wheezing
 Children with allergies have a 30% increased risk of
developing asthma
 Genes play an important role in the susceptibility to
develop asthma

43. Types of Asthma Allergic
(Extrinsic)
 more common (90% of all cases) & typically develops in
childhood.
 Approximately 80% of children with asthma also have
documented allergies.
 there is a family history of allergies.
 Allergic asthma often goes into remission in early
adulthood. However, in 75% of cases, the asthma
reappears later.

44. Types of Asthma: Non allergic
(Intrinsic)
 represents about 10% of all cases.
 develops after the age of 30 & is not typically associated
with allergies.
 Women are more frequently involved , cases respiratory
tract infection.
 The condition can be difficult to treat and symptoms are
often chronic and year-round.

46. Asthma Exams, Tests &
Treatment
Exams and tests:
 lung (or pulmonary) function tests (spirometer, or peak
flow meter) which measure lung function.
 Blood tests give a picture of your overall health; specific
tests also measure levels of immunoglobulin E (IgE), a
key antibody that's released during an allergic reaction.
 X-ray exam of you in order to visualize the structures
inside your chest, including the heart, lungs, and bones.
Treatment:
bronchodilators/ inhalers

48. Anaphylaxis
 Anaphylaxis is the most severe allergic reaction and is
potentially life threatening.
 Anaphylaxis is rare. The vast majority of people will
never have an anaphylactic reaction.
 The most common causes of anaphylaxis include drugs,
such as penicillin, insect stings, foods, X-ray dye, latex,
and exercise.
 The symptoms of anaphylaxis may vary and can include
hives, tongue swelling, vomiting, and even shock.

50. Allergy diagnosis
 Skin prick test
 Blood Test
 Patch test

51. Skin prick test

52. Blood Test

53. Patch test

54. Treatments
 Allergen immunotherapy
 Rush immunotherapy (RIT)
 Homeopathic remedies
 Avoiding exposure

55. Allergen immunotherapy

56. Rush immunotherapy (RIT)
 very quick
 shots given every few hours, instead of every few days
or weeks, to increase the tolerance to an allergen
 patients receiving both Omalizumab (monoclonal
antibody) & RIT had fewer adverse symptoms than
those receiving either treatment alone
 Pretreatment of Omalizumab enhances both the efficacy
& the safety of Rush immunotherapy

57. Homeopathic remedies
 Lycopodium, Pulsatilla and sulfur can be useful in
reducing allergic respons
 Intestinal commensal bacterial flora or eating the right
kind of yoghurt can also be used for inhibiting the
development of allergic responses to food related
allergens

59. Avoiding exposure
 personal hygiene may be the best alternative for
reducing allergies
 Persons prone to respiratory symptoms should avoid
exposure to allergens; they should cover their noses or
wear pollen/dust masks while going outside or exercising
during pollen season
 Air purifiers and cleaning of air vents and duct scan help
in cleansing the air.
 Avoid exposure to stored clothes in boxes or wardrobes
for months after removal from storage and wash them
before wearing
 to avoid the pets