Chronic cough is defined as a cough with duration of more than 4 weeks.
Prior to referral, consider the following common causes of chronic cough:
- Recurrent post-infective cough
- Prolonged post-infective cough (pertussis, mycoplasma)
- Cough as part of the asthma symptom complex
- Protracted bronchitis
- Habit cough
Recurrent post-infective cough:
Most common in children of pre-school age. Episodes are triggered by a viral URTI. Typically the cough is a dry paroxysmal cough that occurs through day and night and disturbs sleep. It may be worse with exercise. The cough is not associated with wheeze or shortness of breath. The paroxysms can last for up to a minute and can result in vomiting or dry retching. In the interval between paroxysms, the child is asymptomatic. The paroxysms can occasionally be quite pronounced. The episodes often last for 10-14 days then resolve until the next URTI. The child is asymptomatic between episodes. Episodes tend to cluster through winter and are less frequent through summer. The cough is a result of transient increase in cough receptor sensitivity. It is not dangerous and usually does not respond to anti-tussives, inhaled or oral steroids or bronchodilators. The parents require a clear explanation of the condition and no pharmacological therapy.
Prolonged post-infective cough:
Pertussis is the most common cause of prolonged post-infective cough. Mycoplasma pneumonia can cause a similar symptom complex. Characteristically, the previously well child develops URTI like symptoms for a few days which I followed by a dry paroxysmal cough similar to that referred to above with asymptomatic intervals between paroxysms. The episode in prolonged post-infective cough can last for several months. Treatment with azythromycin reduces the period of infectivity but does not alter the clinical course of the episode. Anti-tussives are ineffective.
In the year following resolution of the episode, children can develop the recurrent post-infective cough described above.
If children who have pre-existing asthma develop pertussis, their symptoms may easily be misinterpreted as unstable asthma resulting in inappropriate escalation of asthma therapy.
Cough as part of the asthma symptom complex:
Cough can be a component of the asthma symptom complex but cough in the absence of wheeze or shortness of breath is usually not asthma, rather recurrent post-infective cough.
Protracted bronchitis:
Protracted bronchitis is a low grade infection which results in an isolated chronic moist cough in a previously well child which is more prominent on waking in the morning. There is absence of pointers to a specific underlying cause. The cough improves transiently with standard short 5 day courses of antibiotics to recur on completion of the course. Clinical examination and chest x-ray are usually normal . The cough will usually resolve completely after a more prolonged course of antibiotic, usually amoxicillin/clavulinic acid, over 3-4 weeks. Failure to respond to such a treatment would require referral to a respiratory physician.
Habit/psychogenic cough:
There are two types of habit cough. The classic habit cough that most commonly occurs in teenage girls is a harsh 'honking' cough that can be heard from the waiting room. It can be very persistent through the days but settles once the child is asleep. It is not associated with shortness of breath of sputum production. The second habit cough is the annoying 'throat clearing' cough. This typically occurs in boys aged 7-10 years and is related to the common 'transient tic disorder'. Both require reassurance but minimal further investigation. Protracted habit/psychogenic cough may benefit from referral for distraction therapies and /or psychological support.
When to refer
Pointers to a specific underlying cause for chronic cough that would require referral:
- Auscultatory findings of crackles or differential breath sounds
- Barking cough from birth
- Chest wall deformity
- Dyspnoea - on exertion or at rest
- Failure to thrive or weight loss
- Feeding difficulties - particularly coughing in association with feeds
- Finger clubbing
- Haemoptysis
- Neurodevelopmental abnormality
- Recurrent pneumonia
- Habit/psychogenic cough of > 3 months duration
- Recurrent episodes of protracted bronchitis
- Chronic moist cough which fails to respond to prolonged antibiotic course
ReferNew Link
Resources and links
Guideline developed by RCH Respiratory Medicine. First published March 2013,
Please read Copyright and Disclaimer.