Thursday 11 February 2016

Better FOAM - are you getting the picture? (Easter egg - persistent cough in children)

I have an apology to make.  When I wrote about how to tell the difference between bronchiolitis and viral induced wheeze, I talked too much.  I know this thanks to a wonderful audience of GPs who are attending a series of paediatric masterclasses here in Sheffield.  When I described the way to use the prodrome of the illness (as described in the post linked above) I could tell from the faces in the audience that my explanation hadn't yet hit the mark.  Then I put up this slide:

This, coupled with a description of the presenting complaint* for the two conditions seemed to work and I'd like to think that everyone then understood what I was saying.
* With bronchiolitis, the parent usually describes a day by day gradual worsening of the symptoms; with viral wheeze the child often goes from snotty to very wheezy over the space of a few hours.

Pictures, coupled with explanations are a powerful tool for teaching.  I don't have the time to make pictures as much as I would like to, but I will try to do so more often.  Thankfully I learned my lesson just in time, as I was going to write about children who present with persistent cough this week.  Once again, pictures will be needed.  Here I go:

Persistent or Chronic Cough in Children

Children are often brought to GPs and EDs with a cough as the primary symptom.  It is not uncommon for the cough to be reported as having been there for weeks or months.  These histories of protracted coughs tend to cause a variety of responses including a mixture of scepticism and anxiety.  My initial thought of, 'Has this child really been coughing for weeks?' is followed by 'Could it be tuberculosis?'  Both responses are valid.

There are essentially four groups of cough that are present over the space of weeks or months.  The first and most common of these is the cough that comes and goes.  These children are almost invariably having repeated viral upper respiratory tract infections (URTI).  For this reason, the first task is to establish whether the cough ever resolves, leaving periods of normality, however brief.

The second group is those that have a dry but persistent cough that never seems to get worse but never goes away.  In the absence of any red flags (see below) or other clues, this may be normal.  About one in five children (1) are reported to have a daily cough.  Most have no underlying abnormality.  Some have a behavioural element or a relatively benign cause such as post-nasal drip.

The third group is the slowly resolving cough.  Coughs often persist for weeks after an infection has gone.  Even following a simple viral URTI, a large proportion of children cough for weeks afterwards.  Sometimes, such as with bronchiolitis or pertussis, the cough takes even longer.  (2) The important thing is to establish whether the cough is resolving, however slowly.

The final group is the one to watch out for.  If the cough is getting worse, and lasts for more than eight weeks and is getting worse then the likelihood of pathology is much higher.  Most children will present well before eight weeks, so a single course of broad spectrum antibiotics will usually have been tried.  If the cough is getting worse despite this or there are other red flags, the child should be referred.

The red flags that suggest that referral is needed are fairly intuitive:

Where a benign cause is suspected, then treatment can be directed accordingly:

In all cases, smoking cessation is likely to help.

Suspected infection - if there has been a temporary improvement from antibiotics and the child has a chronic wet cough, this may need a longer course (e.g. two weeks) of a second line antibiotic (e.g. Co-amoxiclav)

Post nasal drip - steroid nasal spray/ antihistamines

Behavioural - reassure and advise to distract the child.  The family must avoid any reinforcing behaviours of their own.

One thing that is not recommended is a trial of systemic steroids in chronic cough.(3)  Cough as an isolated symptom, without any wheeze or other indication is very unlikely to be due to asthma.  Steroids may however, mask a mediastinal lymphoma in rare cases.

Symptomatic treatment of the cough is also best avoided.  There are no effective cough remedies in children that do not have significant adverse effects.

So, when a child presents and you are told that the cough has been going on for 6-8 weeks that doesn't mean a lot without the pattern of cough and associated features.

In most cases no treatment is needed.  If explaining that doesn't go down well with the parent, instead of prescribing something anyway, why not draw them a picture?

Edward Snelson
Head of the Sheffield Medical Artists Consortium

  1. J C de Jongste, M D Shields,  Chronic cough in children, Thorax 2003;58:998-1003 doi:10.1136/thorax.58.11.998
  2. Thompson, M, Duration of symptoms of respiratory tract infections in children: systematic review, BMJ 2013;347:f7027
  3. Chang, A, "Isolated cough: probably not asthma" Arch Dis Child. 1999 Mar; 80(3): 211–213