dealing withallergy

a practical guideto the management of

food allergy and anaphylaxis

foodallergyDEALING WITH

CONTENTSAllergy terms 2

Food allergy 3

What sort of symptoms does food allergy cause? 4

Allergy testing 5

What is the significance of a positive allergy test? 5

Are all food reactions caused by allergies? 6

Anaphylaxis—A medical emergency 7

Who is at risk of anaphylaxis? 7

How is anaphylaxis recognised? 8

How much does is take to trigger a severe reaction? 9

What preventive measures can be taken? 10

What are the major traps? 12

What is the emergency treatment? 13

Using the EpiPen 13

Does using the EpiPen hurt? 14

When should the EpiPen be used? 14

What are the side-effects of adrenaline? 14

Have an action plan 15

What additional forms of treatment are there? 16

What should be done after giving adrenaline? 16

What if you don’t have adrenaline on hand? 16

Where can more information be obtained? ibc

Other resources ibc


a practical guideto the management of

food allergy and anaphylaxis

ALLERGY TERMS

Allergies occur when an overactive immune system producesantibodies against substances in the environment that are normallyharmless.

Allergens are allergy-causing substances. Common ones are pollens,dust mites, animal hairs, and in some cases, the protein components ofcertain foods. Normally, the immune system recognises that thesesubstances are harmless, and ignores them.

Atopy is the inherited tendency towards allergies. In atopic people the immune system mistakenly reacts to allergens as if they were invadingparasites. In the general population, about 40% of people are atopic.

Eczema is a chronic, extremely itchy skin rash (dermatitis) which can occur on the face, arms, legs, and the rest of the body in severe cases.

IgE antibodies are responsible for triggering allergic reactions.Normally IgE antibodies protect us from parasites. They are present in the bloodstream, and at all the body surfaces where parasites might attack,especially the skin, mouth, throat, lungs, stomach and intestines. Whenthey come into contact with an allergen, IgE antibodies trigger a chainreaction with the release of various defensive chemicals into the tissuescausing inflammation.

Anaphylaxis is a severe and potentially life threatening allergicreaction due to the sudden release of histamine and other defensivechemicals into the tissues. The release requires only very small amounts of allergen coming into contact with specific IgE antibodies attached to mast cells under the surface of the skin or mucous membranes.

Histamine is the main defensive chemical responsible for the early symptoms of an allergic reaction (including itch). Antihistamine drugs work by blocking its effects.

Adrenaline is one of the body’s natural stress hormones. Whengiven as a medication it is the most effective and most rapidly actingtreatment for anaphylaxis. In the USA, adrenaline is known as epinephrine.

2

COMMON

FOOD

ALLERGENS

egg

peanut

milk

other nuts

sesame

seafood

3

food allergyALLERGIES OCCUR WHEN AN OVERACTIVE IMMUNE SYSTEM

PRODUCES IgE ANTIBODIES AGAINST SUBSTANCES

IN THE ENVIRONMENT THAT ARE NORMALLY HARMLESS .

FOOD ALLERGY is mainly a problem of infants, toddlers and youngchildren. Surveys show that between 5% and 8% of children in the 0-5 yearage range have a food allergy.

In most cases, the first clinical evidence of a food allergy occurs during thefirst 12 months. Fortunately, most grow out of their food allergies before they reach school age or during the primary school years. In adult life about1% of people have a food allergy.

The most common food allergies are to egg, milk and peanut. However,the incidence of particular food allergies varies from country-to-country,and also within a particular country, according to cultural and age-relatedfood choices.

In more than 90% of cases food allergy is associated with atopic eczema,typically beginning in the first year of life. The reverse is not necessarily the case, however—only around one-third of children with eczema have anidentifiable food allergy.

Although it’s hard to predict accurately which children will grow out of theirallergy, it’s extremely rare for milk and egg allergies to persist beyondchildhood. Peanut, other nuts and fish are the ones most likely to persist.New food allergies can occasionally arise in adult life, most commonly withcrustaceans (prawn, lobster, and crab) and other more exotic foods that aregenerally not eaten in childhood. Wheat and soy can cause allergies inchildren, but they tend to be mild and transient.

At the same time as they are growing out of their food allergies and eczema,many children develop allergies to dust mites, pollens or animal hair—inhalant allergens—associated with asthma and/or hay fever symptoms.

food allergyDEALING WITH

4

Mild food allergy may only cause a little chronic eczema on the face and arms,and the cause-and-effect relationship with food may not be obvious. More markedreactions may cause an acute rash around the mouth, with redness and swelling ofthe face, and the child may break out in hives all over. Breathing difficultiesand/or vomiting can follow. A severe reaction may progress rapidly and developinto full-blown ANAPHYLAXIS—A POTENTIALLY LIFE-THREATENING SITUATION

requiring emergency treatment.

Most affected children are allergic to only one or two foods, but the more highlyallergic child may have allergies to three or four. Although almost any of the foodsmentioned above can cause severe reactions, PEANUT, MILK AND EGG ARE THE

ONES MOST LIKELY TO CAUSE ANAPHYLAXIS.

What sort of symptoms does food allergy cause?


FACIAL ECZEMA in infants is often the

first sign of a food allergy. Because of

the intensity of the itch, the infant

scratches or rubs the face frequently.

This causes the rash to appear at contact

points, e.g. on the cheeks, with sparing

of the skin around the nose—as shown

in these young children.

Early features

of a

food allergy

reaction

rash around the mouth

redness and swelling of the face

hives all over the body

breathing difficulties

vomiting

5

SKIN PRICK TESTS for allergies involve putting a small dropof allergen solution onto the forearm and gently prickingthe skin, allowing a tiny amount of allergen to seep into thesuperficial layer of the skin. A local reaction will occur ifthere are IgE antibodies present against the particularallergen. This involves the release of histamine into the skin,causing a small, itchy wheal—rather like a mosquito bite—to develop at the site of the prick within 10-15 minutes.

Blood tests for IgE antibodies (known as RAST tests) can alsobe done. In practice, they are somewhat less reliable. Theyrequire taking blood from a vein, and the results take a day or two to come back, so skin prick tests are generallypreferred. However, if skin testing is not readily availableRAST testing is a satisfactory alternative.

What is the significance of a positive allergy test?

Food related IgE antibodies picked up by skin or RAST

tests may or may not be associated with symptoms.A positive test can only be interpreted as an allergy if it isassociated with typical symptoms triggered by allergen exposure. Small skin testwheals (≤3 x 3 mm) and weak RAST reactions (1+) are hardly ever associated with symptoms of allergy. Large wheals (≥6 x 6 mm) and strong RAST reactions(≥3+) are often associated with symptoms. The higher the antibody levels are,the greater the risk of a serious reaction occurring.

Allergy testing


SKIN TESTING can be performed in

babies as young as 3 months.

The procedure is not painful, and if

performed by experienced professionals

is not dangerous. However, results must

be interpreted with caution, particularly

in the first 9-10 months, because the

skin is less reactive in infancy.

In babies with eczema or a history of

clinical reactions to a food, a positive

skin test, even if small, is usually

clinically significant. Negative tests

should be checked at 12 months’ of age.

If the clinical history is suspicious and

the skin tests remain negative, the child

is more likely to have food intolerances

rather than a food allergy.

6

Many people in the community experience adverse reactions to certain foods,but in most cases these are FOOD INTOLERANCES rather than true allergies.Intolerances are not caused through the immune system, and IgE antibodies arenot involved. Reactions are triggered by various natural or added chemicalcomponents of foods, which produce symptoms by irritating nerve endings indifferent parts of the body. Symptoms vary according to individual susceptibility,and can include stomach and bowel trouble, headaches, irritability, or recurrenthives and swellings. Allergy tests are of no help in identifying food intolerances.

Intolerances can sometimes cause serious reactions that can be hard to distinguishfrom an allergy. In extreme cases, symptoms resembling anaphylaxis can occur—ANAPHYLACTOID REACTIONS—and may require emergency treatment.

Are all food reactions caused by allergies?


For further information about food intolerances,see FRIENDLY FOOD (Murdoch Books).

Copies can be obtained from your bookstore, or email:[email protected]

FOOD INTOLERANCE

7

Anaphylaxis is a severe, rapidly progressive allergic reaction thatcan be life threatening unless treated immediately.

It is a frightening experience for all concerned. Children and parents often take along time to recover from the trauma of their first reaction, and many continue tolive in fear of having another one.

In the general population, about 1 in every 200 children will develop an anaphylacticreaction at some time, most often due to a food allergy. Of those with a knownfood allergy, about 1 in 5 will experience a severe reaction at some stage.

Any child with a food allergy has the potential to develop anaphylaxis, even whenprevious reactions have been relatively mild.

Who is at risk of anaphylaxis?


anaphylaxis

The risk of

anaphylaxis

may be

increased if:

the child is highly sensitised (skin test reaction ≥6 x 6 mm)

the child has multiple food allergies

the child has a peanut allergy

the child’s carers or family are:

poorly informed

insufficiently vigilant

unwilling to remove all sources of allergen from the child’s environment

Fatality is rare. Deaths have usually occurred when the food was unknowinglyeaten, and when emergency adrenaline was not available. Eating away from home presents the greatest risk. In the USA it has been estimated that there are150 deaths per year from food anaphylaxis.

In children with ASTHMA, paying attention to good control may lessen the risk of death from a severe reaction.

a medical emergency

8


Symptoms of anaphylaxis can begin WITHIN MINUTES OF EXPOSURE

and can progress very rapidly.

Rapidly progressive swelling of the lips,

tongue, face and eyes together with

hives or welts spreading quickly over the

body—as shown at right—are common

early signs of anaphylaxis.

Typical

signs are

Rapidly progressive swelling of the lips, face and/or eyes

Hives or welts spreading quickly over the body

Breathing difficulty caused by swelling of the tongue or throat, wheezing or asthma

Acute distress—the child may look very pale, anxious and agitated

Light-headedness or collapse—the child may become weak and floppy, may complain of feeling faint, or may lose consciousness

Any combination of these signs indicates that emergency treatment is required.

Early recognition and prompt treatment can be life-saving.

anaphylaxisrecognised?

HOW IS

In very young

children

rubbing of the face and eyes

a rash around the mouth

spitting out the food

coughing

screaming

vomiting

In older

children

and adults

itching or irritation in the mouth

throat constriction

hives, itching or flushing

wheezing

a sense of dread

9


How much does it take to trigger a severe reaction?There is NO HARD-AND-FAST RULE to indicate the amount of food needed to trigger anaphylaxis. The more sensitive the child, the less it takes to trigger a serious reaction. A tiny fragment of peanut can be enough. So cansmall amounts of allergen lodged in the serrations of a knife previously used to spread peanut butter or to cut cheese. In extreme cases superficial contactwith the skin, mouth or eye, or inhaling airborne particles can trigger asignificant reaction.

Food allergy reactions should always be taken seriously, even if the symptomsare minor. They indicate that the individual is ‘sensitised’ and is potentially atrisk of having a life-threatening anaphylactic reaction in the future.

The development of full-blown anaphylaxis isusually preceded by early warning symptoms.

If in doubt,don’t wait:

Give theemergencytreatment first—then call for help.

10

Make sure you get a MedicAlert® bracelet or necklet for the child to wear. This will provide vital information about the nature of the problem in an emergency.


The most important thing is to avoid accidental exposure. Ideally, the relevantfood(s) should be banned from the home environment. The policy at pre-schooland school will depend on the nature and severity of the allergy and the maturityof the child.

Implementing successful avoidance measures requires awareness and cooperationby all those involved in caring for the child. Complete safety cannot beguaranteed, and accidents can sometimes happen despite the best efforts of all involved. Don’t become complacent just because the child has had a good safety record.

Parents

and

family

members

Be alert

Be careful at home, as well as when eating out

Read all labels and learn about food

Be assertive; educate others

Plan trips/outings and take a supply of safe food

Ensure that others can easily recognize your child as being at risk

Teach your child how to recognize the food allergen and how to identify hidden ingredients

Never coerce the child with food allergy to eat a food he or she rejects

Learn how to use emergency adrenaline, and have a crisis plan

What preventive measures can be taken?

Available from: AUSTRALIA MEDICALERT® FOUNDATION

Phone 1800 882 222 Fax 1800 643 259 www.medicalert.com.au

11


School

teachers

and

carers

Acknowledge your duty of care:

to provide a safe environment for your students

to administer first aid if necessary

Know which children are at risk, which foods are involved

Display a photo of the child at risk in a prominent location

Take note of specialist medical advice in developing avoidance policies

Listen carefully to parents’ concerns—they are the ones who know most about the child’s problem

Never offer the child with food allergy any food not approved by the parents

Ask parents to provide safe snacks and treats to enable the child to participate in birthday celebrations and other special occasions

Be vigilant but discreet with supervision

Avoid stigmatizing the child and deal effectively with any bullying

Learn how and when to administer emergency adrenaline

12


Eating away from home:

Careless behaviour by friends and relatives.

Giving in to the pestering behaviour of young children.

Unlabeled / hidden ingredients at fast food outlets and food stalls.

Ignorant or dismissive behaviour by shop and restaurant staff.

Contaminated utensils, workbenches and spreads in takeaway food outlets.

At school or child-care places:

Ignorant or dismissive behaviour by staff and voluntary helpers.

Cross-contamination of food during preparation.

Cross-contamination when foods are mixed on plates.

Contaminated surfaces, books and toys by grubby fingers.

Inadvertent use of artwork materials such as milk cartons, egg crates,nutshells and eggshells.

Cooking activities using allergenic food.

Bullying or coercive behaviour by other children using the allergenic food.

What are the major traps?In the home:

Failure to read food labels carefully.

Continuing to use the allergenic food in the family home—accidental exposurecan occur from food-scraps, spills or contamination of kitchen benches, utensilsand food containers. In extreme cases cooking fumes may carry sufficient allergen to set off a reaction.

13


What is the emergency treatment?ADRENALINE given as an injection into the muscle is the most effective FIRST AID

treatment for anaphylaxis.

EPIPEN is a disposable pre-loaded automatic injection device containing a singledose (0.3mg) of adrenaline. It can be self-administered, or given by a bystander as immediate first-aid treatment. For children under 30kg there is version thatcontains half the adult dose (EPIPEN JR.).

For infants and toddlers under 15kg, the dose must be adjusted according to thechild’s weight (Adrenaline BP 1:1000, 0.01ml/kg). The treating doctor shouldcalculate the appropriate dose. The adrenaline will need to be drawn up from anampoule and given with a needle and syringe. An injection into the thigh muscleis the fastest and safest method.

USING THE EPIPEN

1Pull off the grey safety cap.

2Place the black tipagainst the fleshy part ofthe outer thigh.

3Push the EPIPEN hardagainst the leg until itactivates, and hold itthere for 10 seconds.

4After the adrenalinehas been injectedwithdraw the needleand discard thedevice safely.

Have an EPIPEN TRAINER available so that you can show other people what todo if they are not familiar with its use. It’s also helpful to keep spare photocopies of the diagram and instructions to hand out.

14


Does using the EpiPen hurt?

It is no more painful than the needle used for vaccine shots. The needle is 15 mm long, and is sharp and thin.

When should the EpiPen be used?

ANAPHYLAXIS IS POTENTIALLY FATAL. Make sure the EPIPEN is readilyaccessible—symptoms can worsen suddenly and you may be caught off guard if it’s not on hand.

Adrenaline works best when used early. Look for the typical features ofanaphylaxis—swelling of the lips, face and/or eyes; spreading hives or welts;breathing difficulty; distress (pale, anxious, agitated); weakness; light-headedness.When any combination of these features is present, and especially if they aregetting worse or there is a previous history of rapid progression, ADRENALINE

SHOULD BE GIVEN IMMEDIATELY. In an emergency it can be given throughclothing if necessary.

Don’t hesitate in the hope that the child might get better without treatment.Symptoms can come and go in the early stages as the body tries to counteract the reaction, but things can go bad very quickly once the body’s defenses areexhausted.

It’s better to be on the safe side—more harm can come from not using adrenalinethan from using it.

What are the side-effects of adrenaline?

Whether given as a medication or released naturally by the body, adrenaline cancause racing of the pulse, shakiness, cold shivers, and a pale appearance.Its main effects wear off quickly, but the child may be left feeling washed out for a few hours.

In an otherwise healthy child, the benefits of using adrenaline far outweigh anypossible harm that could occur. (For a list of special precautions see theConsumer Medicine Information in the EPIPEN package insert.)

15


action planbe prepared

HAVE AN

At home:

Keep the EPIPEN easily accessible (but out of reach of small children).

Make sure anyone who comes to look after the child when you’re out knowswhere it is and how to use it.

Display phone numbers for the local doctor and ambulance near the telephone.

If relevant, have phone numbers of friends and relatives who can come and lookafter the other children in case you have to take the child to hospital.

Get a mobile phone and put the important numbers into the memory bank.

Don’t forget to take the EPIPEN and other medications with you when you go out with the child and when you go on holidays.

At pre-school and school:

Make sure the EPIPEN is readily available and that everybody knows where it’s kept.

All staff members who may be responsible for supervising the child should be familiar with the use of the EPIPEN.

Establish who will be responsible for phoning the parents and emergency services in the event of a reaction.

Find a nearby doctor who is willing to be available in the event of a reaction.

Take the EPIPEN and any other medications on all outings and camps.

IT ’S EASY TO GET FLUSTERED

WHEN THERE’S A CRISIS , SO IT’S BEST TO HAVE

A WELL THOUGHT-OUT ACTION PLAN

Make sure the EpiPen goes wherever the child goes!

16


What additional forms of treatment are there?

Antihistamines can be given by mouth or injection. They generally take atleast 20-30 minutes to work, and although they may help suppress hives and skinswellings, they don’t help with the most dangerous manifestations of anaphylaxis(breathing difficulties, collapse, and allergic shock).

Corticosteroid drugs such as prednisone, prednisolone, and hydrocortisoneare designed to suppress inflammation. They take at least 2-3 hours to beginhaving an effect, but can be useful to prevent some of the after-effects of a severeallergic reaction. The option of using these medications should be discussed with your specialist. Although cortisone-type drugs can have side-effects whenused over long periods, short-term treatment (even in high doses) is generallyquite safe.

Antihistamines and corticosteroids are valuable ADDITIONAL formsof treatment but should never be used instead of adrenaline foranaphylaxis.

What should be done after giving adrenaline?

Adrenaline wears off quickly, and anaphylaxis can rebound within 20-30 minutes.Medical attention should be sought as soon as possible after using the EPIPEN®.If there’s no doctor immediately available nearby, call an ambulance and have thechild taken to hospital for observation.

What if you don’t have any adrenaline on hand?

CALL AN AMBULANCE IMMEDIATELY. Make sure you tell them over the phone that the child is having an anaphylactic reaction—then they’ll be sure to dispatchan ambulance with officers who are trained and authorised to give adrenaline.

If the child stops breathing, give mouth-to-mouth. If the child is unconscious, andyou can’t feel a pulse at the front of the neck or a heartbeat in the chest, give CPR.

FACTS: The Food Anaphylactic Children Training and Support Association www.allergyfacts.org.au

A support group for families of children who have had food relatedanaphylactic reactions.

FACTS provides: information kits; educational videos, books and leaflets;educational lectures by specialists; telephone support and counselling;newsletter; and a member contact list.

MORE INFORMATION

OTHER RESOURCES

AUSTRALASIAN SOCIETY OF CLINICAL IMMUNOLOGY & ALLERGY (ASCIA)

Education Resources: www.allergy.org.au/aer/infobulletins

THE RECOGNITION, MANAGEMENT AND PREVENTION OF ANAPHYLAXIS

IN CHILDCARE, PRE-SCHOOL AND SCHOOL. 1998

Department of Education, Training & Employment; and the Women’s andChildren’s Hospital, Adelaide, SA. Phone: 08 8204 6875 Fax: 08 8204 6885email: [email protected]

THE ANAPHYLAXIS CAMPAIGN

2 Clockhouse Road, Farnborough, Hampshire GU14 7QY UK

Phone: 01 252 542029 Fax: 01 252 377140www.anaphylaxis.org.uk

THE FOOD ALLERGY NETWORK

10400 Eaton Place, Suite 107, Fairfax VA, 22030 USA

Phone: 703 691 3179 Fax: 703 691 2713email: [email protected] www.foodallergy.org

ALLERGY AWARENESS ASSOCIATION INC

Box 56117 Dominion Rd., Auckland NZPhone: 09 623 3912; 09 303 2024 Fax: 09 623 0091Outside Auckland: freephone 0800 34 0800 email: [email protected] www.everybody.co.nz/centre_all.html

ANAPHYLAXIS NETWORK OF CANADA

P.O. Box 57524, 1500 Royal York Road, Toronto, Ontario, Canada M9P 3B6

www.anaphylaxis.org

Copies of this booklet, and the accompanying videotape or CD

DEALING WITH FOOD ALLERGY can be obtained from:

Allergy Unit, RPA Hospital Phone:02 9565 1464 Fax:02 9519 8420

[email protected]

© 2002 Velencia Soutter, Anne Swain, Robert Loblay

S U Z Y K I N G D E S I G N 0 2 9 5 5 5 2 0 7 7

Refer to the package insert Consumer Medicine Informationbefore using any of the products mentioned in this booklet.


This booklet has been reviewed prior to publication by

For further information on allergies, visit www.allergy.org.au

australasian society of clinical immunology and allergy inc.

dealing withallergy

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