Pediatric Allergy and Immunology

These conditions are often caused by allergic reactions, with symptoms that primarily affect a child’s nose, sinuses, eyes, face, and ability to breathe comfortably.

Allergic conjunctivitis

This is a form of conjunctivitis (pink eye) caused by allergens rather than viral or bacterial infection. Common symptoms include reddish eyes that are itchy, burning, puffy, or watery.

Allergic rhinitis (hay fever)

Cold-like symptoms (such as runny nose, nasal congestion, sneezing, coughing, watery eyes, and fatigue) caused by breathing in allergens such as pollen, pet dander, dust mites, or mold spores. Children may be more likely to develop symptoms during times of year when the specific allergens that trigger their rhinitis are more prevalent (seasonal allergies).

Asthma

Narrowing of the airways (the tubes that carry oxygen from your nose and throat to your lungs), causing symptoms such as shortness of breath, cough, wheezing, and tightness in the chest.

Chronic rhinosinusitis (chronic sinusitis)

Long-term (12 weeks or more) swelling of the sinuses of the nose and face, which can result in chronic runny nose, congestion, difficulty breathing, pain or tenderness in the face, and other symptoms.

Nasal polyps

Small, non-cancerous growths of tissue in the nose or sinuses. They are often associated with asthma and other allergic conditions that cause chronic nasal inflammation. Polyps may block nasal passages and make it more difficult to breathe.

These allergic conditions affect the digestive tract, including the esophagus, stomach, and intestines. They include:

Eosinophilic esophagitis

Food allergies trigger overproduction of a type of white blood cells called eosinophils, which collect in the esophagus (tube that connects the mouth and stomach). This can cause difficulty swallowing, heartburn, and chest pain.

Food protein-induced enterocolitis syndrome (FPIES)

Eating certain foods can trigger symptoms similar to severe gastroenteritis (stomach flu), such as vomiting, diarrhea, dehydration, belly pain, and chills. Symptoms usually begin a few hours after eating.

These are complex conditions that result in either a weakened immune system (immunodeficiency) or an immune system that malfunctions and reacts improperly to real or misidentified threats (immune dysregulation).

Many of these conditions are genetic and present at birth (inborn errors of immunity, also known as primary immunodeficiencies). However, immunodeficiency can also be caused by outside factors like infections, medications, or cancer (secondary immunodeficiencies). Specific conditions include:

Adenosine deaminase (ADA) deficiency

The body is unable to produce enough of the adenosine deaminase (ADA) enzyme due to a genetic defect. This can eventually impair the body’s ability to create healthy white blood cells, which are critically important for protection against infections. ADA deficiency is a common underlying cause of moderate-to-severe immunodeficiency disorders.

Hypereosinophilic syndrome

Extremely high levels of eosinophils (a type of white blood cell) in the bloodstream trigger inflammation throughout the body, which can damage organs over time. Symptoms depend on which organs are affected, but may include skin rashes, cough, fatigue, belly pain, chest pain, or nausea.

Hypogammaglobulinemia

This occurs when the body has a low level of antibodies, which are proteins the immune system uses to fight infections. Children with this condition are more susceptible to developing longer and more frequent infections (such as ear infections, bronchitis, pneumonia, stomach flu, skin rashes, and others).

Severe combined immunodeficiency (SCID)

This occurs when the body is completely unable to create working copies of at least one type of white blood cells responsible for fighting infections. As a result, children with the condition have little to no immune function, and even common, mild illnesses can be life-threatening.

These conditions are frequently caused by allergic reactions, with symptoms that primarily affect the skin. They include:

Angioedema

Swelling in the lower layers of skin caused by fluid leaking from blood vessels. It is especially common in lips, eyelids, hands, and tongue, but can occur anywhere in the body — including airways, which can make breathing more difficult. Children are sometimes born with the condition (hereditary angioedema), but it can also be triggered by allergies, reactions to certain drugs, or repetitive vibrations.

Atopic dermatitis (eczema)

Dry, itchy skin rashes that may hurt or ooze. They happen when the skin has trouble holding in moisture and keeping out irritants and germs.

Contact dermatitis

Dry, itchy, cracked, or scaly rash with potentially painful or oozing skin caused by direct contact with allergens or chemical irritants (such as harsh soaps, perfumes, or poison ivy).

Hives (urticaria)

Skin rashes that feature raised, itchy bumps. They may appear reddish or pinkish on people with lighter skin, but not discolored (or only slightly lighter or darker) on people with darker skin.

Systemic allergic reactions affect multiple parts of the body, including the skin, respiratory system, and gastrointestinal tract.

Severe systemic reactions can lead to anaphylaxis, a life-threatening situation that causes sudden, rapidly progressing symptoms throughout the body. Early signs may include skin rashes, swelling, difficulty breathing, and dizziness.

If your child is experiencing symptoms of anaphylaxis, you should do two things immediately: give them epinephrine if you have it available (this is usually administered via an epi pen), and call 911. Without emergency treatment, anaphylaxis will progress to loss of consciousness, inability to breathe, lack of blood flow to vital organs, and possibly death. Allergies that are most likely to cause systemic reactions and anaphylaxis in children include:

Drug allergies

Allergic reactions to certain medications. Unlike side effects, symptoms are caused by an overactive immune response, rather than an expected consequence of the drug itself. Most drug allergies cause mild rashes or cold-like symptoms, but in severe cases can cause anaphylaxis.

Food allergies

Allergic reactions to eating certain foods, such as milk, peanuts, shellfish, soy, or wheat. Symptoms usually develop within minutes to hours of eating and can be severe (or life-threatening) for some individuals, even if previous reactions were less severe. Food allergies are the most common trigger for anaphylaxis in children.

Insect sting allergies

Allergic reactions caused by stings from certain insects, particularly bees, wasps, and ants. For people with milder allergies, a sting may only cause swelling, pain, or rashes like hives near the site of the sting. Severe reactions can cause anaphylaxis.