Can infants have allergies?
A food allergy is an immune response to certain foods. It is a common condition that affects more than 6% of children and 4% of adults in the US. Factors that cause the development of food allergy include age, genetics, allergens (food) and person’s immune system response. However, while some may develop food allergies later on in life, most people develop them as infants and grow out of them by adulthood. So yes, infants can have allergies.
Why do allergic reactions happen?
The presence of certain ingredient (allergen) in our food leads our body to detect it as a foreign material and subsequently reacts to it. An infant allergic to any food allergen means that their immune system is more sensitive to that allergen than the general population.
Our immune system has specific pathways to differentiate harmful material from useful ones. There are special molecules known as antigen presenting cells in our blood, tissues and organs that detect the harmful foreign material in our body and present it to the immune system which then activate and fight against it. Normally, food product joins with these antigen presenting cells and suppress our immune system. This suppression of immune system is known as oral tolerance. Failure of this is the root cause of food allergy.
Major protein release due to the activation of our immune system is IgE antibody. Food allergy may be related to release of IgE or any other mechanism. When food is detected as an allergen by antigen presenting cells (detects foreign material), the immune system is activated and IgE antibody is released. Attachment of IgE antibodies to basophils and mast cells (cells present in our blood) causes the release of chemical mediators such as leukotrienes, histamine, and prostaglandins (effector molecules) and affect many systems of the body especially respiratory system, vascular system, gastrointestinal system and cardiovascular system. This is how a food allergen affects multiple organs of the body and caused a life-threatening situation.
Common food allergies symptoms:
- Dyspnea (difficulty in breathing)
- Cyanosis (blue color of skin)
- Decrease blood pressure
- Cramps in abdomen and vomiting
- Swelling of the affected part e.g tongue
- Shock is the adverse side effect and may lead to death
Food allergy risk factors
Young children are prone to having allergies more than adults. This explains that maturity of gut might be a risk factor in the progression of allergy. There is a little chance of having a food allergy to a food product that was included in our childhood food. One study was about the increasing prevalence of peanut allergy in UK children than in children Israel because of the absence of peanut in children’s food in the UK Other factors are the disturbance of the gut normal environment and pH of the intestine.
Antibodies are highly specific for its target. Immune system continues producing that specific antigen as a part of its defense mechanism in order to deal with second exposure. So, the presence of IgE in our blood that binds to an allergen is a specific marker.
What to give infants for allergies
Removal of food ingredient from our food is the only successful therapy. Drug of choice for food allergy is epinephrine. The patient should be properly advised and trained for self-injection of epinephrine. Some drugs that are specific for food allergy are antihistamines, corticosteroids, and drugs that dilate our respiratory pathway such as beta blockers.