2. INTRODUCTION
• Chronic cough in children 14 years and
younger usually is defined as a daily cough
lasting four or more weeks. (This definition is based upon
expert consensus, as expressed in guidelines from the American College of Chest
Physicians (ACCP) and Thoracic Society of Australia and New Zealand (TSANZ)
• The British Thoracic Society (BTS) utilizes a
threshold of eight weeks duration, which is
the threshold used to define chronic cough in
adults.
3. Classification
• Specific cough — Specific cough refers to a
chronic cough that is ultimately attributable to
an underlying physiologic cause.
• Nonspecific cough — Conversely, a
"nonspecific" cough is defined as a chronic
cough that does not have an identifiable cause
after a reasonable evaluation.
4. EPIDEMIOLOGY
• Prevalence: The reported prevalence of chronic cough
varies depending on many factors, including the
definition of chronicity used in the studies, age of
children, and how cough is determined.
• prevalence of chronic cough of 22% among
preschoolers & approximately 10% in school age
children without colds.
• Burden: An Australian multicenter study found that
75% of parents sought ≥5 doctor visits (14% sought ≥15
consultations) for their child's cough.
5. PATHOPHYSIOLOGY
• An intact cough mechanism (afferent and central limb)
and apparatus (efferent limb) is essential to maintain
respiratory health.
• Cough also enhances mucociliary clearance in both
healthy individuals and those with lung disease.
• The cough pathway, a complex reflex arc, can be
simplified into the afferent, central, and efferent
pathways.
• The cough pathway may be self-initiated (eg, voluntary
cough) or a reflex mechanism.
• Cough has three mechanical physiologic phases:
inspiratory, compressive, and expiratory.
6. Causes of chronic cough in children
• Pulmonary causes.
• Extrapulmonary causes.
7. Primary cause Risk factors or mechanisms Major evaluation method
Pulmonary causes
Aspiration* (recurrent small
volume)
Primary swallowing dysfunction or
laryngeal disorders,
gastroesophageal reflux, achalasia
Swallowing assessment (eg, video
fluoroscopic) and other evaluation as
indicated¶
Asthma, cough-dominant
asthma
Genetics, environment, atopy, post-
acute respiratory infections
Lung function, airway hyperresponsiveness
Chronic endobronchial
suppurative disease*
(protracted bacterial bronchitis,
chronic suppurative lung
disease, bronchiectasis)
Cystic fibrosis
Immunodeficiency (primary or
secondary) Primary ciliary
dyskinesia
Sweat test, genetic screening
Evaluation of immune functionCilia
biopsy, genetic testing
Chronic pneumonia Chronic atelectasis, mucous
plugging,
Pathogens include tuberculosis,
nontuberculosis mycobacteria,
mycoplasma, fungi, and chlamydia
Chest CT, bronchoscopy
Relevant microbial assessment (eg,
QuantiFERON gold and Gene Xpert for
tuberculosis)
Eosinophilic lung disease Primary or secondary (ie, related to
parasitic disease)
Bloods and bronchoalveolar lavage
8. Primary cause Risk factors or mechanisms Major evaluation method
Pulmonary causes
Inhaled retained foreign
body
Young child, history of choking (even if
daysor weeks before cough onset)
Bronchoscopy
Interstitial lung disease Primary genetic abnormality, post-severe
infection bronchiolitis obliterans,
autoimmune disease, radiation, drugs
Relevant genetic or autoimmune test, ±
lung biopsy
Mechanical inefficiency Tracheobronchomalacia and other airway
anomalies
Vascular rings or other anomalies that
cause tracheal narrowing
Dynamic bronchoscopyChest CT
with contrast
Chest MRI (if vascular cause suspected)
Noninfective
bronchitis*
Exposure to environmental pollutants
(eg,tobacco smoke, fungi, traffic)
History and removal of trigger
Post infection
(self-resolving)
Viral infections, pertussis, parapertussis PCR and/or serology
Space-occupying
lesions
Cysts and tumors Chest CT or MRI scan
9. Primary cause Risk factors or mechanisms Major evaluation method
Extrapulmonary causes
Cardiac May cause cough due to airway
compression, pulmonary edema, or
arrhythmia
ECG and other evaluation as
indicated
Ear disease Oto-respiratory reflex (Arnold reflex), in
which stimulation of the auricular branch
of the vagus nerve triggers cough
Examination of the ear canal, and
removal of the object or treatment
of disease that istriggering the
cough
Esophageal
disorders
Gastroesophageal reflux (acid and non-
acid)
Esophageal pH monitoring or
impedance monitoring, ± endoscopy
Medications ACE inhibitors (common); any inhaled
medication, proton pump inhibitors,
otherdrugs (uncommon)
Certain other medications (eg, cytotoxic
drugs) may be associated with
interstitiallung disease
Discontinuation of medication
Evaluation for interstitial lung
disease (eg,HRCT)
Habit cough
(tic cough)
May be isolated, but more likely if other
tics are present
Suppressibility, distractibility,
suggestibility, variability, and the
presence of a premonitory sensation;
cough absent during sleep.
10. DIAGNOSTIC APPROACH
• The systematic evaluation of a child with
chronic cough starts with a targeted detailed
history, physical examination, Investigations.
11. History
• Specific cough pointers – Key clinical features that
predict a specific cause of cough during the initial
evaluation (warning signs or "pointers") include:
• Wet/productive chronic cough
• Wheezing or dyspnea
• Onset after an episode of choking.
• Neonatal onset of symptoms
• Any other associated medical conditions (cardiac,
neurologic, autoimmune or immunodeficiency)
o Note: In young children, wet cough is substituted for
productive cough.
12. Cough characteristics
• Cough characteristics:
• Observe for the characteristics of the cough (sound and pattern) first if it
occurs spontaneously during the interview.
• If not present, ask the child to cough (ie, requested cough), which
sometimes requires coaxing and imitation in young children.
• Also, ask the parent(s) if they have a recording of their child's cough.
• These cough characteristics are important factors in determining the
diagnostic approach.
13. Cough characteristic Suggested underlying pathology
Barking or brassy cough Tracheomalacia, habit cough (habit
cough). If acute: Croup
Honking or 'goose-like' cough Tracheomalacia, habit cough (tic cough),
somatic cough disorder (psychogenic
cough)
Paroxysmal cough (with or without
inspiratory whoop)
Pertussis and parapertussis
Staccato cough Chlamydia in infants
Chronic wet or productive cough only in the
mornings
Suppurative lung diseases (eg,
bronchiectasis, cystic fibrosis)
Wet or productive cough Presence of endobronchial secretions
18. Physical examination
Poor growth or
thinness
Suggests chronic illness.
Dysmorphism,
evidence of a
genetic
syndrome
anatomic abnormalities or swallowing dysfunction with aspiration.
Skin Eczema – Suggests atopic disease.
Other rashes – Evidence of a recent rash raises the possibility of a triggering viral
infection, or impetigo, which is more common in patients with an immune deficiency.
Head and neck Allergic "shiners," swollen nasal turbinates, nasal obstruction, nasal polyps, or allergic
nasal crease
– Suggests allergic disease (a controversial cause of chronic cough).
Lymphadenopathy – Suggests immunodeficiency, malignancy, or chronic infection.
Ears Tympanic membrane scarring or otorrhea – Suggests the possibility of primary ciliary
dyskinesia.
Objects or disease in the ear canal – Suggests the possibility that cough is triggered by
the otogenic reflex (a rare cause of chronic cough).
Mouth Hoarseness – Suggests aspiration or vocal cord dysfunction.
Tonsillar hypertrophy or pharyngeal cobblestoning – Suggests allergic disease.
High-arched or cleft palate – Suggests possibility of congenital anomalies that might be
associated with swallowing disorders or aspiration.
19. Physical examination
Heart Abnormal heart location – Dextrocardia is present in 50 percent of patients
with primary ciliary dyskinesia.
Abnormal heart sounds or pulses – Suggests possible congenital
cardiovascular anomalies, which can cause chronic cough due to airway
compression, pulmonary edema, or arrhythmia.
Abdomen Abnormal liver size or texture – Suggests chronic liver disease, which could be
due to cystic fibrosis.
Splenomegaly – Suggests portal hypertension, including due to cystic fibrosis-
related liver disease. Splenomegaly also may be caused by chronic infection,
malignancy, storage diseases, or hemoglobinopathies.
Situs inversus (spleen on the right and liver on the left) – Situs inversus is
present in 50 percent of patients with primary ciliary dyskinesia but may be
difficult to perceive on abdominal examination.
Genitourinary Rectal prolapse – Suggests cystic fibrosis.
Extremities Edema – Suggests cardiac disease.
Cyanosis or digital clubbing – Suggests bronchiectasis or interstitial lung
disease.
20. Chest examination
• Inspection –
• Observe for increased work of breathing, retractions, accessory muscle use,
and chest wall hyperinflation or deformity.
• Chest wall abnormalities such as hyperinflation, bell-chest, and presence of
Harrison sulci indicate presence of an underlying disease, usually
obstructive airways disease.
• Chronic cough in association with other chest wall anomalies reflective of
poor chest wall expansion (eg, kyphoscoliosis, Poland syndrome) may be
indicative of poor cough clearance and thus increased risk of
bronchiectasis.
• Tracheomalacia is associated with pectus excavatum.
21. Auscultation:
Auscultate for abnormal breath sounds, including reduced intensity,
asymmetry, wheezing, stridor, or crackles.
• A unilateral wheeze is always abnormal and may represent an inhaled
foreign body or other causes of airway obstruction.
• Polyphonic wheezing (ie, many sounds that start and stop at different
times) with cough is typical of asthma; the wheezing occurs on
expiration and sometimes also on inspiration.
• Other causes of polyphonic wheezing in children with chronic cough
include bronchiolitis obliterans, bronchiectasis (cystic fibrosis, allergic
bronchopulmonary aspergillosis, primary ciliary dyskinesia),
bronchopulmonary dysplasia, heart failure, immunodeficiency, and
aspiration.
22. • Monophonic wheezing (single pitch wheeze) should always raise
suspicion of large airway obstruction caused by foreign body
aspiration or malacia and/or stenosis of the central airways.
• In addition, vascular rings, lymphadenopathy, and mediastinal
tumors can cause extrinsic large airway obstruction.
• Tuberculosis should always be considered in a child with a
monophonic wheeze, particularly in areas where the disease is
prevalent.
• In children with tuberculosis, wheezing may be caused by several
mechanisms: extrinsic compression from hilar lymphadenopathy,
tuberculoma, or secondary bronchiectasis.
24. Chest radiograph
• A chest radiograph should be obtained as part of an evaluation in children
with chronic cough .
• An abnormal chest radiograph is a very reliable indicator that there is a
specific cause of cough.
• However, a normal chest radiograph does not exclude specific cough or an
underlying disease process.
• A normal radiograph is reassuring but does not exclude a variety of
pathologic conditions, including foreign body, asthma, early cystic fibrosis,
and bronchiectasis.
25. • Hyperinflation – Unilateral lung hyperinflation may suggest
presence of foreign body aspiration.
• Bilateral hyperinflation is most often caused by asthma but
can also be found in other chronic respiratory illnesses
such as cystic fibrosis, aspiration, primary ciliary
dyskinesia, bronchiolitis obliterans.
26. • Bilateral peribronchial accentuation with one or more focal consolidated
infiltrates –
• These findings arealso seen with diffuse airway inflammation, including
asthma, protracted bacterial bronchitis (PBB), or disorders of impaired
airway clearance (eg, ciliary dyskinesia and cystic fibrosis).
• Infiltrates are most commonly seen in the right middle lobe.
• Abnormalities of the pleura – Chronic pleural effusion and pleural thickening
all suggest underlying lung disease as the cause of the chronic cough.
27. • Right middle lobe changes – This distribution is frequently seen in patients
with obstructive airway disease, eg, asthma ; it reflects atelectasis and
appears in the right middle lobe because the collateral ventilation in this
lobe is underdeveloped in comparison with the other lobes.
• Right middle lobesyndrome may also be caused by other causes, eg,
immunodeficiency
28. • Linear atelectasis, dilated, and thickened airways (ie, tram-tracking or
parallel lines, ring shadows on cross section) –
• This appearance is consistent with bronchiectasis.
• Other findings in bronchiectasis are irregular peripheral opacities that
may represent mucopurulent plugs.
29. • Lung or lobar collapse – This finding is associated with chronic airway
obstruction that may be intraluminal, such as foreign body or mucus
plugs , or extraluminal from a mass causing airway compression.
30. • Mediastinal widening – This finding in children suggests chronic infection,
marked lymphadenopathy, or neoplasm. In an infant or young child, the most
common cause of mediastinal is a normal thymus.
• If the structure is not readily identified on plain film, it can be further
characterized by ultrasound, computed tomography (CT), or magnetic
resonance imaging (MRI).
31. • Cardiac abnormalities – A large or abnormally shaped heart suggests a
primary cardiac defect.
• A large pulmonary artery may be caused by primary or secondary
pulmonary hypertension.
• Right-sided arch is associated with vascular sling or ring and tracheomalacia
32. ADDITIONAL INVESTIGATIONS
• Spirometry — When appropriate for the child's age (>3 years in a pediatric
laboratory and >6 years in other laboratories), spirometry should be
obtained as part of an evaluation in children with chronic cough .
• Normal spirometry does not exclude disease.
• An obstructive pattern in the spirometry indicates obstructive airway
disease such as asthma or suppurative lung disease, while a restrictive
pattern reflects an interstitial or chest wall restrictive processes.
33. ADDITIONAL INVESTIGATIONS
• Flexible bronchoscopy (F.B, airway malacia, tracheoesophageal fistula, or
stenosis)
• Esophageal pH or multichannel intraluminal impedance (MII)
monitoring (GERD).
• Sinus imaging – Cough is sometimes reported with chronic sinusitis.
• Chest CT scans – suppurative lung disease, mass seen on the chest
radiograph, or nonresolving pulmonary consolidation, a vascular
abnormality is also suspected (eg, sling or ring).
• Magnetic resonance imaging (MRI) may be more appropriate in selected
circumstances such as for concurrent cardiac and cardiac vessel evaluation.
• Tests for tuberculosis.
• Echocardiogram.
34. SUBSEQUENT FOLLOW-UP AND
MANAGEMENT
• In the management of chronic cough, the key principles are:
o Targeted treatment for the suspected or confirmed cause of the cough, as
determined by a systematic evaluation
o Identifying and mitigating exacerbation factors, such as exposure to
environmental tobacco smoke
o Defining and discussing the expectations of, and the effect of the cough on,
the child and parent(s)
35. Specific cough
• Specific cough — Treatment of children with a specific cough is directed at
the suspected cause. In some cases, referral to a specialist for further
investigation and management is appropriate.
• It is important to reassess the child periodically to determine whether
treatment has been optimized and to confirm the diagnosis.
• Some children may have more than one cause of specific cough, such as
asthma with a congenital abnormality of the airway.
36. Nonspecific cough
• Watchful waiting –
• For most patients with nonspecific cough (dry cough with no specific
pointers), the first step is a period of watchful waiting.
• Most cases of nonspecific cough are related to a viral illness (postviral
cough);
• the underlying physiology is thought to be due to increased sensitivity that
gradually resolves over time (two to four weeks)
37. • Medication trials –
• Some cases of nonspecific cough probably represent a cough-dominant
asthma; this is more likely if the child has other signs of allergic disease
or a family history of asthma.
• Therefore, if the cough is troublesome, it is reasonable to perform an
empiric trial of bronchodilators (short-acting beta2-agonists) or low-dose
inhaled corticosteroids (<400 micrograms budesonide equivalent daily).
• If empiric treatment is undertaken, the trial should be time-limited (two
to four weeks) and the medication should not be given chronically unless
the underlying diagnosis is firmly established.
38. • Medication trials –
• Gastroesophageal reflux disease (GERD) is probably an unusual cause of
chronic cough in otherwise healthy children.
• Nonetheless, in selected children with nonspecific cough and other
symptoms suggestive of GERD (such as heartburn or regurgitation), it is
reasonable to do an empiric trial of treatment for GERD for four weeks,
using acid-suppressing medications such as a proton pump inhibitor(PPI).
• Assessing the response to therapy – When medications are trialed,
reassessment of the child is recommended in two to four weeks, which is the
"time to response" for most medications.
39. • Family expectations and counseling –
• The significant burden of chronic cough in children for families has been
well documented and should always be considered when consulting
families.
• A number of studies have documented the frequent consultations by parents
of children with chronic cough, with three-quarters consulting a doctor more
than five times for their child's cough.
• Additionally the parental worry can lead to the use of nonspecific
medications, which may not be suitable due to lack of efficacy and safety
concerns
40. • Cough suppressants –
• Over-the-counter cold and cough suppressants are not recommended for
the treatment of chronic cough in children.
• There is no evidence that they improve symptoms in this age group, and
significant safety concerns have been raised about their use in young
children.
• The US Food and Drug Administration has issued a public health advisory
against the use of these drugs for young children.
41. • Avoidance of tobacco smoke –
• There is evidence that environmental exposure to tobacco smoke increases
respiratory infections and thus the risk for chronic cough in children.
• Parents who smoke should be counseled to stop smoking and guided to
support for smoking cessation.
• Until the parent is able to completely stop smoking, they should not smoke
in the presence of children, including in the family car, even with the window
open.
• The clinician should also ask adolescent patients about the possibility of
tobacco use and provide strong support for smoking cessation.
42. • Alternative therapies – In the absence of specific treatments for the chronic
symptom, many families will try alternative therapies, including honey and
echinacea.