Wheezing or “whistling” is common in children under 3 years of age. In fact, they are a frequent reason for consultation in Pediatrics. Up to 30% of children wheeze at some point in their lives. The frequency has increased considerably in recent years and, in children under 6 years of age, it has gone from 6% to 10%.
It presents with four types of
- recurrent cough
- respiratory distress
- repeated choking that requires a visit to the emergency department
- “wheezing or whistling that parents hear without the need for pediatric auscultation.
Hospital emergency department specialists diagnose it, in the discharge report, as obstructive bronchitis or wheezing bronchitis, asthmatic bronchitis or, sometimes, infantile asthma attacks.
Parents often ask three main questions: what causes wheezing, what can I do to prevent wheezing, and whether their child will be asthmatic when he or she grows up.
What causes bronchitis
Cold viruses are usually the most common trigger for wheezing bronchitis. The bronchus becomes more or less persistently inflamed and this results in coughing, shortness of breath and bronchospasm.
The pediatrician will exclude that the child has no known causes of recurrent wheezing of known origin such as:
- congenital malformations of the bronchus or lung.
- chronic lung disease
- cystic fibrosis
- vascular rings compressing the trachea or bronchi
- bronchiectasis or abnormal dilatations of the bronchus
- gastroesophageal reflux
- bronchial foreign body after episodes of choking on food or other objects
- immunodeficiencies
- bronchial cilia abnormalities
What to do to prevent bronchitis and treatment
The pediatrician should perform a study when the child has more than three different obstructive bronchitis crises.
It may be indicated to perform a chest X-ray, a sweat test, blood tests, allergological studies in children over 3 years of age (Prick-test on the forearm) and other examinations, depending on the intensity, frequency and complications of bronchitis.
According to the symptoms, the analytical results and the examinations performed, a diagnosis of the phenotype of each child is made. Not all children who receive the famous inhaled nebulizer are the same. And, although inhaled salbutamol is used for the treatment of crises, sometimes oral corticosteroids in short cycles and antibiotics are indicated if there is respiratory superinfection.
Preventive treatment will not always be the same. Preventive treatment with a specific oral medication may be indicated, but sometimes also inhaled corticosteroids, or a combination of both. Also sometimes different associations are made and sometimes none at all, since there is the possibility that they do not respond to preventive therapy. In these cases the solution is to avoid colds and, in some cases, this can only be achieved if they stop attending day care.
The pediatrician should evaluate each case individually, helping the parents a lot in the study, evaluation and understanding of what is happening to the child. Children should not and cannot be compared with each other. Likewise, a follow-up and calendar of events and responses to treatment, as well as prevention, should be made.
My child has bronchitis: will he/she be asthmatic when he/she grows up?
There are five studies that follow children from birth to adulthood. This has allowed us to define 4 phenotypes or clinical forms of children with recurrent wheezing, which will allow us to know if the child will suffer asthma when he/she reaches adulthood:
1) Transient wheezing processes. Children present “wheezing” during the first year of life. It can be before or after bronchiolitis (if it is after bronchiolitis due to respiratory syncytial virus in winter, they are more frequent). Most of them tend to disappear at the age of 3 years but others persist until the age of 6 years. They are usually non-atopic children with no family or personal history of atopy (genetic predisposition to allergy). Risk factors in this group include maternal smoking during pregnancy, male sex, prematurity, presence of older siblings and day-care attendance, which facilitates the transmission of viral infections.
2) Persistent recurrent wheezing in non-atopic children. It manifests during the first year of life, often after bronchiolitis due to respiratory syncytial virus and may persist until the child reaches puberty. It affects boys and girls alike, who usually have no demonstrable allergies and their bronchial hyperresponsiveness improves with age. Pulmonary function in spirometry is normal.
3) Wheezing in atopic or allergic children. They usually start after one year of life and, in some cases, after 3 years of age. It predominates in the male sex. Studies by the allergist are positive and, many times, children also have atopic dermatitis and/or food allergy, especially egg allergy. There is also a family history of atopy, more frequently in the mother. Pulmonary function may alter over time and periodic spirometry should be performed if they suffer recurrent obstructive bronchitis.
4) Severe recurrent intermittent wheezing. It occurs in children under 3 years of age or infants (less than one year old) with important bronchitis crises that require frequent visits to the emergency room, are often admitted and, in the periods between crises, are symptom-free and lead a normal life. They are usually allergic children with a history of atopic dermatitis, egg allergy and positive skin tests for pneumoallergens. It would be similar to the previous group but in children under 3 years of age there is a predictive index to take recurrent wheezing more seriously. In this sense, it should be assessed if there is asthma in any of the parents (especially the mother) or atopic dermatitis, in addition to allergic rhinitis in the child, wheezing that does not occur after colds and blood tests with eosinophilia of more than 4%. The pictures should be evaluated by an allergist and/or pediatric pulmonologist, in addition to the follow-up of the crises by the pediatrician.
On the other hand, there are other phenotypes that have become known over the years. Thus, there are girls who start their crises during adolescence. In other cases, there are girls who start asthma episodes with exertion, during physical exercise, when they are 8-10-12 years old. Likewise, there are skiers who only have crises when they have a cold and make efforts in Nordic skiing on certain days, with a specific degree of humidity and cold.
Depending on age, sex, genetic predisposition, environmental exposure and personal and family history, variable phenotypes appear with the child and over time. Children under 3 years of age are of greater concern due to their young age and early onset, during the first year of life. Asthma remains a disease with many questions.