Peanut Allergy

Peanut Allergy.  We can help you diagnose and manage peanut allergy. 

Peanut allergy is very common and found in about 2% of the childhood population.
It affects about 1-in-50 children, and 1-in-100 adults.

Most feared food allergy

It is the most feared food allergy.  This is because peanut is the most reported cause of death from food allergy. 
However, death from food allergy is an extremely rare event. Nevertheless, peanut allergy needs to be taken seriously.

Diagnosis

To diagnose peanut allergy accurately, you require  a “skin prick test”  or “blood RAST test” for peanut.
we offer this service as part of your consultation at the Childrens Clinic | Allergy Centre, Christchurch. 

Type of reactions

Acute urticaria (hives) is the most common type of reaction following peanut exposure. 
It is associated with eczema, and sometimes asthma, in about half of peanut allergy sufferers.

The symptoms are dose-dependent.  That means, the more peanut that is eaten, the worse and more serious the symptoms.
Even tiny amounts of peanut (for instance some traces of peanut on the lips and a kiss given) are enough to cause a local skin reaction.

Calculations have been made concerning the amount of peanut required to give allergic symptoms.  
The most sensitive people can react to as little as 1/2000th of a peanut. 
However this tiny amount of peanut is not going to cause a serious reaction.

It is thought that up to two kernels of peanut are required to cause a fatal outcome.
With larger amounts of peanut, the reactions can be extremely violent and life threatening.
Under these circumstances, angioedema (tissue welling, especially of the face), bronchospasm (wheezing and asthma) and anaphylaxis (shock) are the symptoms to look out for.  Vomiting and diarrhea are also common.

See “Anaphylaxis” menu tab for more information.

Eczema

Eczema can be caused by a peanut allergy.
In breast-fed babies, if the mother is eating peanut, this can precipitate eczema. 
Peanut allergy can be developed during breast-feeding.
Most people who had a peanut allergy will react on their first exposure to peanut, because they have been sensitized by breast-feeding.

In other words, babies who are just breastfed can also have peanut allergy.  Peanut can get into breast milk though the mother’s diet.

Breastfeeding 

Peanut allergy reaction through the breast milk can be subtle.  Initially the baby gets irritable, and then as the weeks go by the baby’s face gets rashy.  The next step is for the cheeks to become bright red, scaly and dry.  Sometimes the skin will crack and weep. The baby begins to rub his cheeks on the bedding which damages the skin even more.  The rash continues spreading to the chin, the neck and the creases of the arms and legs. Then the whole body begins to feel rough and a fine red rash appears.  This progression occurs over a few weeks to months.

When will it go away?

Usually, peanut allergy is a life-long problem. 
It turns out that about 80% of children with peanut allergy continue with this allergy through to their adult years.
The bigger the skin prick test, the more likely peanut allergy is to persist.
The good news is that most people with a peanut allergy are not seriously affected. 

It may be possible to get tolerance to peanut by consuming tiny amounts each day. 

How serious?

Peanut allergy is potentially very serious.  The best way to measure the degree of reactivity is to do skin prick tests or RAST tests. 
If these tests have high numbers, then the problem is serious and it is very important to be very careful about peanut exposure.
Some people need to carry adrenaline pens.
We can show you how to use these Epipens at the Children Clinic.  

See “Anaphylaxis” menu tab for more information.