• The definition of chronic cough varies but is usually considered to be a cough that persists beyond 6–8 weeks. Coughs caused by uncomplicated respiratory infections will have resolved within this time period.
• Clues to the aetiology lie primarily in:
• the history;
• the nature of the cough (dry or productive-sounding)—it is especially useful if the cough can be heard during the consultation.
• When did the cough start?
• What happened at the start, e.g. was there a respiratory tract infection or a choking episode?
• What has the pattern been?
• Getting worse/better/staying the same?
• Periods without cough?
• Is the cough dry or productive-sounding? It is worth taking some time over this question, as the differential for a dry cough is quite different to that of a productive-sounding cough. Note that it is very unusual for children under 5 years to expectorate sputum, so the term ‘productive-sounding’ is preferred to ‘productive’ when describing a cough associated with increased airway secretions.
• What precipitates the cough, e.g. eating/drinking or exercise?
• Does the cough occur at night?
• Are there any other associated symptoms, e.g. wheeze?
• Are there any previous chest symptoms?
• Is there a history of significant infections?
• Are there any associated symptoms such as:
• dyspepsia (which may suggest GOR);
• loose stools or poor growth (which may suggest CF).
• Are there persistent upper respiratory tract symptoms such as rhinitis, ear infections, or glue ear? The presence of these symptoms may suggest an atopic tendency or possibly PCD.
• Early history:
• prematurity, including any need for intubation;
• transient early neonatal lung disease (may suggest PCD);
• Family history of cough/chest illness.
• Do any other family members or school friends have a similar cough? This may suggest pertussis infection.
A full and careful clinical examination is required, particularly of the upper respiratory tract, including the ears (Arnold’s ear-cough) and chest. If the chest is hyperexpanded and/or wheeze is heard, asthma becomes more likely. Ask the child to cough, and ask the parents if the cough you have heard is typical. Is the cough paroxysmal or dry/tickly Box 4.1 or wet/productive Box 4.2 or barking/tracheal/laryngeal?
The investigation is directed by the type and severity of the cough. If the cough has not been heard in clinic or the parents feel the cough heard in clinic is atypical, then ask them to record the cough at home on audio or video and bring to the next appointment. A symptom diary of the frequency and timing of the cough can also be helpful.
Investigations to consider for a dry cough include:
• exercise test;
• pH study;
• contrast swallow;
Investigations to consider for a productive-sounding cough include:
• cough swab or sputum culture;
• sweat test;
• nasal ciliary biopsy;
• tests of immune function:
• full blood count (FBC);
• total immunoglobulins (Igs);
• functional responses to vaccinations.
• chest CT scan;
• bronchoscopy and BAL.
The management is directed to the likely underlying aetiology.
• Post-pertussis cough requires explanation and reassurance only. The family should be warned that the cough is likely to persist for 3 months, with gradual improvement, but may be exacerbated by any intercurrent upper respiratory tract infection (URTI).
• Cough associated with asthma responds to asthma treatment.
• Chronic productive-sounding cough in otherwise well children is most likely to be caused by persistent low-grade endobronchial infection. This condition has several different names in the literature, including chronic bronchitis, chronic endobronchial infection, and persistent bacterial bronchitis. When there are no abnormal physical findings, and a normal CXR or one showing mild bronchial wall thickening only, and nothing from the history to suggest an alternative diagnosis, it is reasonable to begin treatment with a prolonged course of antibiotics (to ensure no residual bacterial infection driving chronic sputum production) and physiotherapy (to ensure effective airway clearance). Personal practice in Oxford is to give 6 weeks of oral antibiotic, combined with chest physiotherapy, before review. The majority of children respond to this therapy, with no further problems, but, if symptoms persist or recur, then the child should be investigated for an underlying disorder, including tests for CF, immune deficiency, and PCD.
• Habit cough is usually just a habit like any other.
• A child, possibly with very mild tracheomalacia, gets a viral infection that starts them coughing. Because they discover they can make a loud cough, which possibly gets them a bit of attention, this becomes reinforced. Tracheal irritation from the cough itself may also help to perpetuate the cough.
• There is usually no identifiable underlying psychological problem, nor do the majority of children develop other functional problems once their cough resolves (although it can occasionally happen).
• Management of a habit cough starts with explanation and reassurance. Teaching the child some breathing exercises to do when they feel like coughing can also be useful. The majority settle without further action, but occasionally help from a psychologist is needed.
• The now famous ‘cough and bedsheet’ approach1 is rarely used in practice, but alternative distracting therapies, such as sipping warm water when the child feels the desire to cough, may be equally effective.
• Cough associated with other individual conditions is managed according to the cause—each is dealt with in later chapters.
Chang AB (2005). Cough: are children really different to adults? Cough 1, 7.Find this resource:
Lavigne JV, Davis AT, Fauber R (1991). Behavioral management of psychogenic cough: alternative to the ‘bedsheet’ and other aversive techniques. Pediatrics 87, 532–7.Find this resource:
Marchant JM, Masters I.B, Taylor SM, Cox NC, Seymour GJ, Chang AB (2006). Evaluation and outcome of young children with chronic cough. Chest 129, 1132–41.Find this resource:
Shields MD, Bush A, Everard ML, McKenzie S, Primhak R; on behalf of the British Thoracic Society Cough Guideline Group (2008). Recommendations for the assessment and management of cough in children. Thorax 63, 1–15.Find this resource:
1 Cohlan SQ, Stone SM (1984). The cough and the bedsheet. Pediatrics 74, 11–15.