Over the last 15 years scientists have noticed a worldwide increase in the incidence of allergies; the reasons for this is as yet unsure.
Allergies are immune responses that cause abnormal reactions in some individuals.
In our daily lives we all have contact with many allergens such as certain foods, pollens, dust and some medicines.
In people who are allergic, the immune system goes on high alert, and think that a substance, that is either ingested or encountered, is causing harm to the body. Doing what it does best, the immune system tries to protect the body, and releases antibodies called Immuneglobulin E (IgE). These antibodies in turn cause certain cells to release chemicals and these can then trigger symptoms in an allergic individual. Reactions can affect the eyes, nose, throat, skin, respiratory system and /or gastrointestinal tract. The symptoms can range from slightly annoying (like an itch and a sneeze) to serious and even deadly reactions in cases of anaphylaxis.
Every time an individual is exposed to the offending allergen, the immune system will mount a response and a subsequent allergic reaction again. The extent of these reactions may worsen over time, but there is also a chance that children might outgrow certain allergens like milk and eggs.
It is estimated that between 6 and 8% of the paediatric population has some kind of allergy. The tendency to develop allergies is hereditary and can be passed genetically from parents to their offspring. It also seem that there is a bigger chance to inherit those genes if the allergic tendencies come from the maternal side. Interestingly, you don’t inherit a specific allergy, just the general tendency to develop allergies.
Some kids develop allergies with no other family members affected, and if there is one allergy present more can develop over time.
What can cause allergies?
1.Food allergies
Up to 8 % of children are estimated to have one or more food allergies. Cow’s milk, soy, fish, eggs, peanuts and other tree nuts, wheat and shell fish are amongst the most common.
– Cow’s Milk
Up to 3% of children can be allergic to the protein found in Cow’s milk, especially in those younger than 3 years. Remember that the protein found in most formula milk preparations also have a base of Cow’s milk protein. Cow’s milk protein allergy is different than lactose intolerance. Whereas Cow’s milk allergy is an Immune modulated response, lactose intolerance is an inability to break down lactose, which is a sugar. Cow’s milk protein allergy is often outgrown.
– Eggs
As eggs are used in many of kid’s favorite foods, managing an egg allergy can be a bit tricky. Words to look out for to identify hidden egg ingredients are albumin, ovoalbumin, ovomucin, globulin, lecithin and lysozyme. The good news is that most kids, if not all will outgrow this allergy.
– Fish and Shellfish
These allergies are very common and also ones that are not outgrown. Fish and shellfish are from different families and an allergy to one does’t necessary mean an allergy to the other.
– Peanuts and tree nuts
The incidence of these allergies are steadily increasing. Being allergic to peanuts may also have implications and possible cross allergies to almonds, walnuts, hazelnuts sand cashews. There may also be cross reactivity to the legume family (chickpeas and lentils). Children don’t often outgrow these allergies and there may be a risk for anaphylaxis at contact to even small trace amounts of the offending allergen.
– Soy
Children who are allergic to cow’s milk are often also allergic to soy protein. This allergy is far more common amongst babies than adults. Important to note is that soy protein is a very common ingredient in processed foods and meats. Learn to read labels!
– Wheat
A wheat allergy is often confused with Celiac disease but these are not the same. Celiac disease is an insensitivity to gluten ( an ingredient in wheat, barley and rye) and is diagnosed by a biopsy of the small intestine. A person with a wheat allergy develops an immune response to one or several of the proteins in wheat. Ingestion of these proteins in wheat may lead to severe anaphylactic reactions in certain individuals. people with Celiac disease will not develop anaphylaxis on ingestion of gluten.
Children may have cross reactivity between products. If there is a known allergy to latex, there may also be reactivity to avocado, banana, kiwi and chestnuts.
2. Airborne Allergens
This group of allergens are carried through the air and are often the cause of hay-fever symptoms. Common allergens include house dust mite and the pollens of grasses, trees and weeds. Pollen allergies are often seasonal.
Mould and cockroach allergies are also on the rise and are often found in poorly ventilated spaces and outside, in poor drainage areas and compost piles. Cockroach allergies are directly linked to the rising incidence of Asthma in our inner city childhood population.
Allergies to pet dander and saliva are common in children. The allergy can be either to the pet saliva or against their urine. As the urine and saliva dries the protein particles can become airborne and work their way into soft furnishings and fabrics.
3. Other Common Allergens
Medicines, of which Antibiotics are the most common, may cause allergic reactions. It is important to remember that tests to confirm an antibiotic allergy after a reaction should only be done at least 4-6 weeks after the reaction.
Insect allergies; For some people a sting by a bee or wasp may lead to minor discomfort, swelling and redness, whilst for others it can lead to anaphylaxis. It can also develop later in life, so even if you have been stung before and had no reaction, you can develop anaphylactic reactions with a subsequent sting.
Chemicals in household product and cosmetics can make people break out in hives, although these are not often allergic reactions that are immune mediated
Signs and Symptoms of Allergies.
Symptoms and severity will vary from one child to another. There is a wide range of symptoms and your child can present with one or more of these symptoms, affecting one or more organs in the body.
Some children will develop the so-called Allergic March. This condition usually presents with Eczema and Food allergies in the young baby, progress to Allergic Rhinitis, and then to Asthma in the later childhood years.
When there is an allergy to the airborne allergens there is usually sneezing, chronic blocked or runny noses (usually with clear and watery secretions) and itchy or swollen eyes present.
Wheezing with a tight chest or throat, coughing, a hoarse voice, severe vomiting and/or fainting spells are more associated with food, medicine or insect venom allergies.
Diagnosis of Allergies
Some allergies can be very easy to diagnose, whilst some can require the skills of Sherlock Holmes. Flu-like symptoms that do not get better after about a week and that occurs every year at the same time might be some of the telltale signs to look out for.
Consult your Paediatrician if you suspect the possibility. Your Doctor might order skin prick tests to diagnose the most common food or environmental allergens.
In the case of serious allergic reactions, your child might be sent for blood tests to determine especially the risk of anaphylaxis to peanuts and tree nuts.
How are allergies treated?
The treatment of allergies is mostly aimed at control of symptoms as a definitive cure is unfortunately not possible. Avoidance of the offending allergen is probably the best advice, especially in the case of food allergens. Easier said than done, I know! Luckily, many of the allergies are outgrown over time.
It is important to learn to read the labels. A consultation with a paediatric dietician specialising in allergies is extremely valuable and helpful.
Education of the child, their caregivers and educators are extremely important, especially in the case where the little one could have a severe reaction if they get in contact with the allergen.
Avoidance of airborne and environmental allergens is impossible. Doctors may prescribe antihistamines, eye drops and nasal sprays to try and control the symptoms.
Immunotherapy is a modality that is available to desensitise against certain aeroallergens and insect venom. Your child will be referred to an Allergy specialist should this be an option.
Some measures to help with the allergic reactions to airborne allergens are:
Remove carpets, rugs and heavy curtains to minimize house dust mite. Special covers for duvets and pillows are also available to help control this allergen.
In case of pollen allergy, it might help to keep windows and doors closed, when the pollen count is high. Encouraging your little one to take a bath or shower after being outside might also be of benefit.
Remember that your Paediatrician is always available to help navigate and walk the allergy path with you and your child.
Xoxo, Dr Christa