Doctor, does my Baby have Asthma?

Infant wheezers are often stressful for their parents and can be challenging for their doctors. However, with the help of a good clinical history, a careful objective exam and sometimes a few ancillary tests, it is usually relatively easy to effectively approach and treat most small children with common recurrent wheezing and the long-time prognosis is normally good. The fortunately rare cases of serious respiratory illness must, of course, be identified and sent to reference centres.

Recurrent wheezing and coughing are common symptoms in infants and young children- They are usually of a transient nature and associated with viral infections but can also be the early manifestation of long-lasting asthma.

It is well known that viral infections can provoke wheezing in young children and are also an important trigger of asthma exacerbation in older patients.

There are several viruses associated with asthma symptoms, but the most important is the Respiratory Syncytial Virus (RSV), particularly in young infants, who can be severely affected.

Babies who suffer an episode of acute RSV bronchiolitis, may develop recurrent wheezing and some of them are later diagnosed as asthmatics.

It may be questioned whether RSV truly induces bronchial hyper-reactivity in previously healthy children, or if it only uncovers some pre-existing vulnerability in predisposed individuals.

Recent studies show that palivizumab prophylaxis versus placebo, significantly reduces the incidence of recurrent wheezing in preterm infants, thus suggesting that RSV infection may, in itself, be an inducer of bronchial hyper-reactivity. This might occur namely by triggering neurogenic inflammation, as suggested by some experimental data in mice. This viral induced hyper-reactivity may be one of the causes of childhood non atopic persistent recurrent wheezing, usually a transitory condition.

There may also be predisposing factors, like narrow airways or genetically conditioned Th2 inflammation. Small airways are responsible for a well-known transient wheezing pattern described in several studies, whereas Th2 inflammation, triggered by viruses or allergens may cause persistent atopic asthma (“true” asthma).

It may be difficult for the paediatrician to identify the disease pattern at an early stage. Nevertheless, the good news is that most of these children do not develop asthma in the future. For those who do, there is usually effective available treatment.

Fortunately, asthma medication may work even in children without “true asthma” who eventually outgrow their condition. It is important to elucidate their parents, that although these children are prescribed actual asthma drugs, this does not mean they have a permanent condition that requires medication for life.