allergy and anaphylaxis

1. ALLERGY & ANAPHYLAXIS
BY
DR. DAMINENI RAVI TEJA
1st year resident

2. CASE STUDY
A 4-month-old baby boy with a history of eczema presented to
our emergency room with vomiting, urticaria and cyanosis
following first exposure to a banana. He improved with
administration of intramuscular epinephrine. Skin prick tests
showed positive results for both fresh banana (4mm
wheal/15mmerythema) and banana extract (8mm wheal/20mm
erythema).

3. CONCLUSION
Banana is not considered a highly allergenic food.
However, as food allergy becomes more common and
solid foods are being introduced earlier in babies,
banana may become an important allergen to consider in
cases of babies presenting with anaphylaxis.

5. ALLERGY
INDRODUCTION
 Derived from GREEK – ALLOWS means OTHERS and
ERGOS means WORK
 Allergy means an altered state of reactivity to an
antigen and included both types of immune responses
 Other use the term ALLERGY to mean all immune
processes harmful to the host such as hypersensitivity
and autoimmunity
 Allergy is probably most commonly used as a synonym
for “HYPERSENSITIVITY”

6.  For induction of hypersensitivity reaction the host should
have and contact with antigen
 The initial contact sensitizes the immune system
Leading to
 Priming of the appropriate B or T lymphocytes
 This is known as the SENSITIVITY or PRIMING DOSE

7.  Subsequent contact with the allergen causes manifestations of
HYPERSENSITIVITY
 This is known as the SHOCKING dose

8. CLASSIFICATION OF HYPERSENSITIVTY REACTION
 Classified traditionally into
IMMEDIATE and
DELAYED types
 Based on the time required for a sensitized host to develop
clinical reactions on the re-exposure to the antigen
 Immediate and delayed reactions are subdivided into
several distinct clinical types

9. HYPERSENSITIVE
REACTION
IMMEDIATE
(B-CELL or
ANTIBODY
MEDIATED)
ANAPHYLAXIS ATOPY
ANTIBODY
MEDIATED CELL
DAMAGE
ARTHUS
PHENOMENON
SERUM SICKNESS
DELAYED
(T-CELL
MEDICATED)
INFECTION
TUBERCULIN TYPE
CONTACT
DERMATITES

10. COOMBS & GELL classified hypersensitivity reaction into 4 types
based on the different mechanism of pathogenesis
TYPE 1
• Anaphylactic , IgE or regain dependent
TYPE 2
• Cytotoxic or cell stimulating
TYPE 3
• Immune complex or toxic complex
disease
TYPE 4
• Delayed or Cell Mediated
Hypersensitivity

12. TYPE 1: ANAPHYLACTIC ,IgE
Antibodies (Cytotropic IgE antibodies) which are fixed to
surface
sesitises individuals
Antigen combines with the cell fixed antibody
Leading to release of pharmacologically active substances

13.  This occur in two forms
The acute potentially fatal , systemic form called
anaphylaxis
&
The chronic or recurrent , non fatal ,typical
localized form called atophy

14. ANAPHYLAXIS
INTRODUCTION
 The term Anaphylaxis was coined by RICHET (1902)
 Anaphylaxis is a serious allergic reaction, with a rapid
onset it may cause death and requires emergent
diagnosis and treatment
 Food, medication, insect stings and allergen
immunotherapy injection are the most provoking factors
for anaphylaxis
 Although allergic reaction are a common cause of ED
visits anaphylaxis is likely under diagnosed

16. PHATHOPHYSIOLOGY
activation of mast cell and basophiles
Aggregation of high affinity receptors for IgE
mast cells and/or basophiles quickly releases preformed mediators from
secretory granules that includes HISTAMINE,TRPTASE, CARBOXYPEPTIDAASE
A and PROTEOGLYCANS
Upon activation

17. Activation of phospolipase A2 cycyclooxygenases and lipoxygenases
Produces archidonic acid metabolites , including prostaglandins, leukotrienes
and platelet activation factor
Inflammatory cytokine, tumor necrosis factor alpa is
released as performed mediator and also as a late phase
mediator with other cytokines and chemokines

18. CLINICAL CRITERIA FOR ANAPHYLAXIS
 Utricaria, generalized itching or flushing or Oedema of
blips, tongue, uvula or skin developing
Associated with at least one of the following
Respiratory distress or hypoxia
Or
Hypotension or cardiovascular collapse
Or
Associated symptoms of organ dysfunction

19.  Two or more signs or symptoms that occur
 skin/mucosal involvement
 Respiratory compromise
 Hypotension or associated symptoms
 Persistent GI cramps or vomiting
 Consider anaphylaxis when patients are exposed to a
known allergen and develops hypotension

21. Urticaria Flushing
Pruritus

22. CLINICAL FEATURES
 Begins with
 Pruritus
 cutaneous flushing
 urticaria
 c/o lump in the throat and hoarseness
ENT- Or pharyngeal or throat fullness(50%)
Tongue swelling (1-2%)
Uvula edema/ hydrops (1-5%)

23. Respiratory – SOB(45-50%)
Laryngeal oedema or pharyngeal(50-60%)
Rhinitis(30-35%)
 CVS – HTN(30-35%); Chest Pain(4-5%)
 Skin – Utricaria / angioedema (60-90%)
Flushing(45-55%)
Pruritus(2-5%)
GIT - Nausea, emesis, cramps or diarrhea(25-30%)
Neuro – Headache(5-8%)
seizures(1-2%)

24. Laboratory investigation:
 limited to ED settings
 Serum histamine levels elevated for 5 to 30 min (basal plasma
histamine concentrations of 0.3 to 1.0 ng/mL)(unhelpful) as
they typically normal upon ED presentation.
 Serum tryptase level (Normal serum tryptase range is 0-11.4
μg/L) are elevated for several hours and have been proposed for
late confirmation of suspected anaphylactic episode

26. TREATMENT
 Triage for all acute allergic reactions should be at the
highest level of urgency because of sudden deterioration
FIRST LINE:
Start assessment of airway, breathing, circulation
 Initial IV access
 O2 administration
 Cardiac rhythm monitoring
 First line therapies have immediate effect during the
acute stage

27. MANAGEMENT
injected under the skin or into the muscle of your outer thigh only

30. DRUG ADULT DOSE PEDIATRIC DOSE
EPINEPHRINE/ADRINALINE IM: 0.3-0.5 MG IM: 0.01 milligram/kg
Or
EpiPen Junior 0.15
milligram of epinephrine
IV BOLUS: 100 micrograms
over 5-10 min
IV infusion: start at 1
microgram/min; mix 1
milligram in 500 mL NS
and infuse at 0.5 mL/min;
titrate dose as needed

31. DRUG ADULT DOSE PEDIATRIC DOSE
IV infusion: start at 1
microgram/min; mix 1
milligram in 500 mL NS
and infuse at 0.5 mL/min;
titrate dose as needed
IV infusion: 0.1–0.3
microgram/kg per min;
titrate dose as needed;
maximum, 1.5
micrograms/kg per min
Oxygen Titrate to Sao2 ≥90% Titrate to Sao2 ≥90%
IV fluids: NS or LR 1–2 L bolus 10–20 mL/kg bolus

32. SECOND LINE
DRUG ADULT DOSE PEDIATRIC DOSE
H1 Blockers
Diphenhydramine 25–50 milligrams IV, IM, or
PO every 6 h
1 milligram/kg IV, IM, or PO
every 6 h
H2 Blockers
Ranitidine 50 milligrams IV over 5 min 0.5 milligram/kg IV over 5
min
Cimetidine 300 milligrams IV 4–8 milligrams/kg IV
Corticosteroids
Hydrocortisone 250–500 milligrams IV 5–10 milligrams/kg IV
(maximum, 500 milligrams
Methylprednisolone 80–125 milligrams IV 1–2 milligrams/kg IV
(maximum, 125 milligrams
Prednisone 40–60 milligrams PO daily or 20–
30 milligrams PO twice daily
1–2 milligrams/d PO
divided twice a day or daily
To be used after initial IV dose
(for outpatients: 3–5 d; tapering
not required)
To be used after initial IV dose
(for outpatients: 3–5 d; tapering
not required

33. DRUG ADULT DOSE PEDIATRIC DOSE
Treatment of
Bronchospasm
Albuterol (salbutamol) Single treatment: 2.5–5.0
milligrams nebulized
Single treatment: 1.25–2.5
milligrams nebulized
4–6 puffs from MDI with
holding chamber
4–6 puffs from MDI with
holding chamber
Both repeated every 20 min
as needed
Both repeated every 20 min
as needed
Continuous nebulization: 5–
10 milligrams/h
Continuous nebulization: 3–
5 milligrams/h
Ipratropium bromide Single treatment: 250–500
micrograms nebulized
Single treatment: 125–250
micrograms nebulized
4–6 puffs from MDI with
holding chamber
4–6 puffs from MDI with
holding chamber
Both repeated every 20 min
as needed
Both repeated every 20 min
as needed
Magnesium sulfate 2 grams IV over 20 min 25–50 milligrams/kg IV over
20 min

34. DRUG ADULT DOSE PEDIATRIC DOSE
Treatment for Patients on
β-Blockers with
Refractory Hypotension
Glucagon 1 milligram IV every 5 min
until hypotension resolves,
followed by 5–15
micrograms/min infusion
50 micrograms/kg IV every
5 min

35. URTICARIA
• It is a cutaneous reaction marked by acute onset of
pruritic , erythemic wheals of varying size that generally
are described as fleeting
• Many acute urticarial reactions are due to virus,
especially in children
• Obtained a detail history , if an etiological agent can be
identified (eg: cold, exercise, food) further reaction can
be avoided.

36. TREATMENT
 H1 antihistamines, with or without corticosteroids are
usually prescribed
 Epinephrine can be consider in sever
 Addition of H2 antihistamine , may useful in more
severe, chronic or unresponsive cases

37. ANGIODEMA
 Similar reaction as Urticaria
but
Deeper involvement
Characterized by
Oedema formation in dermis
generally
Involving face, neck and distal extremities
Trigger: Angioedema converting enzyme

38. Rx:
• Supportive
• Epinephrine , antihistamines and corticosteroids are not
beneficial
• ICATIBANT , a bradykinin-2 antagonist is affective agent
to reduce swelling and shorten to complete resolution

39. ALLERGIC DRUG REACTION
 10% OF Occurrences
 Penicillin drug most common 90%
 Parental >>> oral (fatal allergic reaction)
 So patients with previous life threatening or anaphylactic reaction to
penicillin should not be given

40. CLINICAL FEATURES
 Serum sickness begins in the 1st or 2nd week after initiation
 Malaise, arthralgia , arthritis , Pruritus , urticarial eruptions,
fever , adenopathy and hepatosplenomegaly are common
signs and symptoms
TREATMENT
 Supportive with oral or parentral antihistamines and
 Corticosteroids

41. REFERENCE
 Anantha Narayana Microbiology
 Baveja Microbiology
 Tintinallies emergency medicine
 Handbook of emergency medicine

42. THANK
YOU