Wheezing only when lying on stomach

[KT361]

My six month old grandaughter only wheezes when you lay her on her stomach. We have heard wheezing when she sits up, but only seldom and is very faint. Asthma is not common in our family, but her little brother does have skin allergies. Do you think she has Asthma, and why does this mainly happen when she is lying down on her stomach. We welcome your response. Thankyou

[National Jewish Health]

It is very unlikely that your granddaughter's wheezing, only in the prone position, would be caused by asthma.  At this age, the airways are still quite small and even slight pressure from a normal adjacent structure, present in only one position, could cause a wheeze that will spontaneously resolve as the airway enlarges.

You should note if the "wheeze" occurs with inspiration or expiration.  If on inspiration, that would more likely be from an upper airway obstruction, such as the larynx, commonly called the voice box.

The positional characteristic of this wheezing raises the question of an anatomic abnormality, of which there are 3 categories:  1) Central abnormalities such as malacia of the larynx, trachea or bronchi and tracheo-bronchial fistulas; 2) Extrinsic airway abnormalities, which are in the chest but outside the trachea and other airways, that result in airway compression, such as abnormally placed large blood vessels; and 3) Intrinsic airway anomalies, such as cysts.

Any of the above can cause wheezing and, in this regard, can mimic asthma.

You might want to ask your granddaughter's pediatrician if there is any reason to consider any of the above.