Everything you need to know about asthma in children

What is asthma?

Asthma is a chronic condition of the airways that manifests in recurrent episodes of obstruction (of the bronchioles) following exposure to different triggers, which may vary among individuals. Examples of triggers include physical exercise, different viruses or specific allergens that a child may be sensitive to, such as cat hair.

What actually happens to our body during an asthmatic attack?

The triggers cause the onset of an inflammatory response in the cells of the immune system, and result in a series of contractions in the muscles surrounding the airways, along with development of edema and secretion of toxins from the cells, causing the production of mucous. This entire process gradually blocks the airways and causes cough, a feeling of suffocation and shortness of breath.
In other words – for those who do not have asthma, a specific virus may cause a mild infection in the upper respiratory tract, that is, it will cause congestion in the nose and cough. For people with asthma, that same virus will cause an inflammatory response leading to hyper-reaction of the lungs, such as in other allergic conditions. Cough and shortness of breath may remain even after the actual virus has been destroyed, as a result of the body’s “over-reaction”.

How common is asthma?

About 12% of children around the world are diagnosed with some degree of asthma (the incidence is between 2-30%). In western worlds, such as in the USA – asthma is the most common complaint in emergency departments, the most common cause of hospitalizations and the most common reason for missing school days.
Interestingly, in about 80% of children, their first presentation will occur only after the age of 6 years. This is important because it tells us that most wheezers will not have asthma when they grow older.
We have a very interesting post on our website about wheezing in infancy (asthma of infancy, coming soon), but one of the important questions that typically comes up is whether we are able to assess which of the young children with asthma of infancy and recurrent episodes of wheezing will develop real asthma in the future.
Well, the answer depends on whether or not the child has risk factors for the development of asthma, such as a parent with asthma, an additional allergic condition such as atopic dermatitis (asthma of the skin) or allergy to food, episodes of wheezing that occur without fever and whether they are exposed to cigarette smoking. But we will talk about all of this in more detail in the post “asthma of infancy”.

So, what are the real causes of asthma?

The causes of asthma are a combination of environmental exposures, biological mechanisms of the body and genetic predisposition. We know that a mutation in one of the 100 areas we have identified in our DNA can bring about an inflammatory process or allergic reaction in the body and increase the risk for asthma or allergy. The individual characteristics of each of these will determine the body’s ability to respond to triggers by causing different types of inflammation and secondary damage to the airways.
In infants and young children, exposure to respiratory viruses can causes a hyperreactive airway and asthmatic attacks during the course of illness. There are some viruses that are very common, such as RSV (find out more about it here), that cause the body to respond with an inflammation that can later go on to produce a tendency for asthma. Exposure to cigarette smoke or air pollution can also affect the severity of the local inflammation and even a fetus’ exposure to maternal smoking has been proven to be one of the risk factors for developing asthma after birth.

What are the signs and symptoms of an asthmatic attack?

The common symptoms include a dry cough, shortness of breath or a feeling of suffocation, which usually worsens during the night or following physical activity.

What are the signs of asthma on physical examination of the child?

Between the episodes the child does not usually suffer from cough and their physical examination is normal.
During an episode, however, auscultation of the lungs will typically reveal decreased air entry, with obstruction on expiration of the air and therefore the expiratory phase is usually prolonged, and often there is excessive phlegm from the inflammation itself.
A chest x-ray during an episode can present as normal but may also show obstructed areas due to the obstruction of the bronchi which can be confused for a pneumonia.

So, how can we tell that it is asthma?

First of all, the diagnosis is based on the medical history. The child will usually be at the right age, present with recurrent episodes of cough and suffocation as a result of exposure to different triggers, will response well to adequate therapy such as nebulisations or puffers (find out the difference between the two here), and will be free of symptoms between the attacks. The child will usually not have any other underlying respiratory illness.
If the child presents to a physician during an attack, and the physician listens to the lungs and finds diffuse wheezing on expiration, this will certainly strengthen the possibility of the diagnosis. But in order to prove that the cause of these signs is asthma and not a different inflammation of the airways or a different cause of obstruction, the child will have to complete some objective examinations, such as pulmonary function tests.

What are pulmonary function tests?

These are a series of objective tests, and their efficacy depends on the child’s cooperation. They are used to assess the flow of air on inhalation and exhalation into a computer, connected to a special opening. With the help of physiological techniques, that are based on physical formulas, we are able to determine whether there is an obstruction of the airways, how severe it is, and to assess the volume of the lungs on inhalation and maximal exhalation and the speed of the flow of air that is exhaled from the mouth within a certain time. Because this test requires the cooperation of the child, only children that are able to understand the instructions of the tests (usually children of the age of 6, but sometimes a bit younger as well) are able to complete this test.
If the technique is right – one can use this test to demonstrate improvement in the flow of air following use of medication that widens the airways, such as Ventolin. A positive test, such as in asthma, means there was significant improvement of over 12% following medication.
Cases that are not clear cut, or if the child is not obstructed and is not showing any reversal of symptoms following medication – additional tests can be carried out, where there is a controlled exposure of different triggers giving us the opportunity to assess response to these triggers.
The most common of these tests is called a stress test, the child is exposed to physical exercise (all while monitoring the length of time and the increase in heart rate) and then you can prove that the child’s pulmonary function tests worsen as part of the response. The next step includes giving the child an airway-widening drug (such as Ventolin) to demonstrate that the airways have re-opened. This is evidence that the child suffers from physical exercise induced asthma.

So, what is the therapy for asthma in pediatrics and what are the goals of therapy?

The goals of therapy in children with asthma is that they live a long and full life, just like any other child, without any physical or mental limitations.
The therapy includes attempts to prevent asthmatic attacks and also education for the parents and child on how to treat an attack as soon as it begins in order to prevent exacerbation. Indeed, the sooner and more adequate the treatment, the easier it is to inhibit the inflammatory process before it gets complicated, leading to missed school days, hospitalization, pneumonia and in severe cases hospitalization in the intensive care unit.
Prevention of attacks can be achieved by reducing exposure to triggers – such as avoidance of cigarette smoking, including environmental exposure to smoking, virus vaccines which are known to worsen attacks (find out more about the influenza virus here) and reducing exposure to known allergens – such as certain plants or domestic animals when a specific allergy is known to exist.
When an attack of shortness of breath begins, it is important to start treatment immediately, with the help of the right therapies and the correct devices, depending on age.
There are local therapies that are given as inhalations, and they act directly on the airways through the mouth, that is nebulizers or puffers. These are the most effective therapies and they have the least side effects, and families who have a child with asthma should really familiarize themselves with these and start treatment prior to visiting the physician. in addition, there are systemic therapies, that are given by mouth (pill or suspension) and in exceptional cases, may be given intravenously at the hospital.
The therapies will always include two different types of products – bronchodilators combined with anti-inflammatory drugs, such as steroids. As mentioned above, these drugs can be administered as nebulizers, puffers with aerochambers or in teenagers are powders given in turbuhalor or diskus. Correct use of these different devices is critical for the medications to enter the small airways properly.

What about preventive treatment between attacks?

There are children that need treatment regularly, between asthmatic attacks, if their asthma disrupts their daily life, affects their pulmonary function, or if they suffer from different allergies and are exposed to triggers on a daily basis. In such cases administration of localized treatment with a steroid puffer with reduce the hyper-reactive response of the airways to the unavoidable triggers.
When the asthma is uncontrolled – it is important to reach out to a physician, and sometimes to one that specializes in pulmonary diseases in children, to prevent both short and long term complications.

So, what happens to children who have asthma when they grow older?

Most of the asthmatic children (about 85%) suffer from mild asthma, and just like in other allergic conditions, they may experience phases with frequent attacks and others with reduced frequency of attacks. Sometimes they go on for years without having an attack. When this is the case, and the children and families are familiar with the condition, it is possible to keep things under control and live a full, quality life. Of-course, one should not avoid physical exercise and it is actually recommended to help maintain a healthy lifestyle. There are some excellent athletes that have asthma, such as David Beckham and the Olympic swimmer Tom Dolan.

Rarely does asthma have a more severe course that requires regular medications. Patients that are hospitalized with severe attacks should be monitored by a pediatric pulmonologist to make sure the pulmonary function tests are not affected and there aren’t recurrent episodes of pneumonia that could potentially exacerbate the condition of the lungs with time.

In summary, this is an important and significant condition that should be managed accurately by a specialist in the field. This is so that your child can reach their full potential, in the most optimal way possible, without any limitations.