Immunology Flashcards
(84 cards)
What is the difference between an allergy and intolerance?
Allergy –> immune reaction usually IgE mediated
Intolerance –> non immune reaction
What tests do you offer to determine a food allergy?
Blood tests for IgE mediated antibodies
THEN Skin prick test or prick-prick test
Why should things like skin prick test, food challenges and atopy patch testing not be done in a primary healthcare or community setting?
Risk of anaphylaxis
If individual DOES NOT have IgE mediated food allergy, what should be done next?
Eliminate suspected allergen for 2-4 weeks, then reintroduce
If a child has cow milk allergy, what advice should be given?
Advice on food avoidance to breast feeding mothers
Info of appropriate hypo-allergenic formula or milk substitute to mother of formula fed babies
When should referral to secondary healthcare be considered in terms of a food allergy?
No response to diet removal of allergen
Child has confirmed IgE food allergy and concurrent asthma
Tests are negative but still strong suspicion of IgE food allergy
What are the 4 immunologically-mediated reactions of drug eruptions?
type I: anaphylactic
type II: Cytotoxic reactions
type III: Immune complex mediated reactions
type IV: T Cell-mediated delayed hypersensitivity reactions
Are immunologically-mediated reactions dose dependent?
No
Are Non-immunologically-mediated reactions dose dependent?
Can be
What is the most common presentation of drug eruption rash?
Exanthematous
What is the second most common presentation of drug eruption rash?
Uticaria
What kind of immunologically mediated reaction is a Exanthematous drug eruption?
Type IV
What are the signs and symptoms of a exanthematous drup eruption?
Wide spread, symmetrical rash Mucous membranes usually spared e.g. mouth Pruritis Mild fever Onset 4-21 days after first taking drug
What are the indicators of potential, severe reaction?
Involvement of mucous membranes and face Facial oedema and erythema Widespread confluent erythema Fever >38.5 Blisters, purpura, necrosis - sloughing of the skin Lyphadenopathy Arthalgia SOB, wheezing
What drugs are associated with exanthematous
Penecillins NSAIDs Erythromycin Phenytoin Anti-Epileptics Allopurinol
What drugs can cause Acute Generalised Exanthematous Pustulosis (AGEP)
Antibiotics
Ca channel blockers
Antimalarials
What drugs can cause drug induced Bullous Pemphigoid?
ACE inhibitors
Penecillin
Furosemide
What drug can cause Linear IgA bullous disease?
Vancomycin
What medications can cause a fixed drug eruption?
Tetracycline, Doxycycline
Paracetamol
NSAIDs
Carbamazepine
What is Steven-Johnsons Syndrome?
Stevens–Johnson syndrome, a form of toxic epidermal necrolysis, is a life-threatening skin condition, in which cell death causes the epidermis to separate from the dermis. The syndrome is thought to be a hypersensitivity complex that affects the skin and the mucous membranes.
What is Toxic Epidermal Necolysis?
The disease causes the top layer of skin (the epidermis) to detach from the lower layers of the skin (the dermis), all over the body, leaving the body susceptible to severe infection. Death usually due to sepsis or multiorgan system failure
What is Acute Generalised Exanthematous Pustulosis?
Uncommon skin eruption. It is characterised by the rapid appearance of areas of red skin studded with small sterile pustules (small blisters filled with white/yellow fluid). There tend to be more disease in skin folds. Facial swelling often arises.
Drugs associated with phototoxicity?
Antibiotics (fluroquinolones, tetracyclines) Thiazide diuretics Amioderone Immunosuppresents Antifungals
What are the two kinds of immune response?
Innate and Adaptive
