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Symptom sorter – cough in children

The GP overview

The symptom GPs love to hate because it can appear so trivial. Reassurance and explanation are often all that is required, and this can build a bond with parents and children. Take parents seriously and sympathetically – nocturnal cough is a destroyer of sleep and family peace.

Differential diagnosis


  • URTI.
  • LRTI.
  • Post-nasal drip (for example, post URTI, allergic rhinitis).
  • Asthma.
  • Pertussis.


  • Inhaled foreign body.
  • GORD.
  • Psychogenic.


  • TB.
  • Cystic fibrosis.
  • Earwax or foreign body in the ear canal.
  • Immune deficiency.
  • Interstitial lung disease.
  • Congenital, e.g. trachea-oesophageal fistula.

Ready reckoner

  URTI LRTI PN drip Asthma Pertussis
Child unwell No Possible No Possible Possible
Chest signs No Yes No Possible No
Spring/summer exacerbation No No Possible Possible No
Marked nasal catarrh Yes No Yes Possible No
Cough >three weeks No Possible Possible Yes Yes

Possible investigations




FBC, ESR/CRP, chest X-ray, serial peak flow or spirometry.

Small print

  • Pertussis serology, sweat test, secondary care investigations (for example, for interstitial lung disease or immune deficiency).
  • FBC, ESR/CRP – WCC raised in infection, marked lymphocytosis in pertussis, ESR/CRP elevated in any inflammatory process.
  • Chest X-ray – may be helpful in LRTI, TB, inhaled foreign body, cystic fibrosis.
  • Serial peak flow or spirometry – to help confirm a diagnosis of asthma.
  • Pertussis serology – if a clinical suspicion of pertussis needs confirming.
  • Sweat test – for cystic fibrosis.
  • Other secondary care investigations – may be required after referral (for example, for interstitial lung disease or immune deficiency).

Top tips

  • Think pertussis in any paroxysmal cough lasting more than three weeks – it is much more common than most people, and many doctors, realise.
  • Educate parents about the likely duration of URTI-related coughs and simple measures to take. Avoid prescribing, as this simply reinforces the tendency to attend the doctor for minor, self-limiting illness.
  • In the asthmatic child, a cough may be a sign of poor control. Check treatment, compliance and inhaler technique.
  • Many parents panic that a cough might harm their child. An explanation that a cough is often simply a way of ‘keeping the lungs clear’ can defuse the situation.

Red flags

  • Parents tend to focus on the cough. In the acute situation, rather more important are symptoms and signs of respiratory distress – the NICE traffic light system for febrile children is useful in the acutely coughing febrile child and will help guide the need for admission.
  • A dramatic and abrupt onset of coughing in a child should make you consider an inhaled foreign body.
  • Beware the ‘poorly controlled asthmatic’ who isn’t thriving – this could be cystic fibrosis.

Dr Keith Hopcroft is a GP in Laindon, Essex.

Dr Vincent Forte is a GP in Gorleston, Norfolk.

The fifth edition of Symptom Sorter is available from Radcliffe Publishing for £34.99.

Symptom Sorter 5th edition



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