Recently I learned a good way to find the answer to a
question. It happened like this-
On a walk in Sheffield
I saw this strange bird:
Unable to find this creature described in a ‘Birds of Britain’ book, I
posted the picture to Facebook and commented that (to me) it looked like a
cross between a turkey and a goose. Most
other Facebookers were similarly unfamiliar with the species but within a short period of time,
I received a response from my niece who declared the bird to be a Muscovy
duck. After quickly confirming this to
be true, I asked how she recognised this bird which is not native to the
UK. The response that came back was
simply that she had searched the internet for "birds which look like a cross
between a turkey and a goose".
Boom.
I had the chance to complete this
lesson, for myself in a clinical context, shortly afterwards when faced with another unfamiliar animal, this time
in the form of a baby with an ambiguous presentation. The child had developed a cough and feeding difficulties
and had now become wheezy. Preemptively, my
diagnostic centres had skipped forward to the disease that I thought I merely
needed to confirm: bronchiolitis. This mental process was interrupted by a cough from the child, and what
a cough it was. It went on and on and on… At the end of the period of coughing, the
child’s face was properly red. The mother informed me that more often than not a spectacular vomit followed these paroxysms of cough.
With the new possibility of whooping cough suggesting
itself, I examined the child with a new mission: confirm findings that are consistent with pertussis infection. I was therefore, properly annoyed to find a wheeze which I felt was more in keeping with
bronchiolitis. Faced with this puzzle and remembering my niece’s
methods, I asked the internet and found that, while not a typical feature of
pertussis infection, wheeze has been well described in a large number of cases of children with whooping cough. (1)
This case reminded that, as primary care clinicians, we don’t
really diagnose infections- we diagnose
syndromes. Bronchiolitis, for example,
is not RSV infection. Bronchiolitis is a
syndrome of wheeze, poor feeding and cough which can lead to severe respiratory
distress, apnoea and feeding or respiratory failure. RSV is one possible cause amongst many
untreatable viruses.
Similarly, despite what I was once taught, croup is not
caused by parainfluenza virus. Any virus
can cause the upper airway swelling that leads to barking cough, possibly stridor and varying
degrees of respiratory distress.
Just to keep me on my toes, children seen to present from time to time with features of multiple syndromes.
The most common bedfellows are croup and viral induced wheeze. When faced with a child who has a barking
cough and a wheeze, one initially questions whether the noise is in fact a
stridor (and rightly so). If it is a
wheeze, then it is a wheeze. If the
child has both croup and viral induced wheeze, ther is no point trying to limit the diagnosis. Just get on and treat both. It occasionally causes a bit of confusion if the child needs admission. I think that some junior doctors take the referral of a child with the diagnosis of viral wheeze and croup together to be a sign of uncertainty, or perhaps dementia.
I would suggest that perhaps wheeze is not a feature of
whooping cough but that it is possible for a baby to have bronchiolitis at the
same time as whooping cough, both caused by pertussis infection. It doesn't really matter though, since the cause
of the infection is only of interest if it can be treated, or transmission
prevented.
There are so many infectious causes of noisy breathing in children. Here is a simple guide to what’s what and what to do about
it:
Many thanks to my niece for teaching me what the internet is for.
Edward Snelson
Ornithopathologist
@sailordoctor
Disclaimer: I take full credit for inventing the use of evidence based medicine in the consulting room.
Reference:
Acknowledgement: This is a slightly different version of a post which I wrote for the Network Locum Blog earlier this year.
