Medical Q&As

Chesty cough - lungs clear?

I have an eleven-week-old baby girl. Her birth weight was 7lbs 2 ounces and she was delivered by caesarean section. She has had a very chesty cough for the past eight weeks. Our doctor prescribed penicillin for her but it did no good. We were back with the doctor on Friday and we were told that there was no infection in her chest. If there is no infection in the chest why does she sound so chesty?

Many young babies suffer from chesty cough and it can be a considerable source of surprise to parents when the doctor tells them that the child’s lungs are clear. That does not mean that there is nothing wrong with the child it simply means that there are no sounds of infection present in the child’s lungs when the doctor listens in with the stethoscope. Cough can be produced by inflammation anywhere along the respiratory tract. Inflammation of the throat can cause a cough as can inflammation of the trachea or windpipe. In the case of your little baby I suspect that the so-called chesty cough is being produced by what we refer to as transmitted noises. These sounds are usually produced by loose mucous in the back of the throat the sound of which is transmitted down the windpipe into the lungs and is perceived by observers as coming from the lungs. Sometimes you can detect a rattling effect if you place your hand on the child’s chest, which further convinces you that the child must be chesty. The mucous that gives rise to the transmitted noises usually comes from the back of the nose and drips down into the throat thereby producing the cough. Many such babies are prone to snuffles and the mucous from the upper respiratory tract is simply dripping down the back of the throat like a dripping tap. We refer to this process as postnasal drip.