Management of Chronic Cough in Children

- Introduction

Chronic cough is defined as the presence of daily cough of more than 4 weeks duration in children aged <14 years old (4). It has been divided into specific and nonspecific cough. Specific cough is usually associated with an underlying disease and non-specific cough indicates prolonged cough in the absence of any symptoms, signs, history, or laboratory findings indicating a specific diagnosis (specific cough pointers) (5). Table (1)

Table (1): Specific cough pointers

Abnormality	Examples of etiology
Symptoms or signs Auscultatory finding	Wheeze Crepitations-any airway lesions (from secretions) or parenchymal disease such as interstitial disease
Cardiac abnormalities	Associated airway abnormalities, cardiac failure, arrhythmia
Chest pain	Arrhythmia, asthma
Chocked	Foreign body inhalation
Dyspnea or tachypnea	Any pulmonary airway or parenchymal disease
Chest wall deformity	Any pulmonary airway or parenchymal disease
Digital clubbing	Suppurative lung disease
Daily wet/ productive cough	Protracted bacterial bronchitis, suppurative lung disease, recurrent aspiration, atypical infections, TB, diffuse panbronchiolitis
Exertional dyspnea	Any airway or parenchymal disease
Facial pain/purulent nasal discharge	Chronic sinusitis, (protracted bacterial bronchitis), primary ciliary dyskinesia
Feeding difficulties	Any serious systemic including pulmonary illness, aspiration
Growth failure	Any serious systemic including pulmonary illness such as cystic fibrosis
Hoarse voice/stridor	Laryngeal cleft/problems, airway abnormalities
Hemoptysis	Suppurative lung disease, vascular abnormalities
Hypoxia/cyanosis	Any airway or parenchymal disease, cardiac disease
Neurodevelopmental abnormalities	Aspiration lung disease
Recurrent pneumonia	Immunodeficiency, atypical infections, suppurative lung disease, congenital lung abnormalities, trachea-esophageal H-type fistula
Recurrent infections	Immunodeficiency
Previous history of chronic lung disease, esophageal disease (neonatal lung disease, esophageal atresia)	Multiple causes (eg, second H-type fistula, bronchiectasis, aspiration, asthma)
Wheeze-monophonic	Large airway obstruction(eg, from froing body aspiration, malacia, and/or stenosis, vascular ring, lymphadenopathy, and mediastinal tumors)
Wheeze-polyphonic	Asthma, bronchiolitis obliterans, bronchiolitis
Tests
Chest radiograph (other than peribronchial changes or spirometry abnormalities)	Any cardiopulmonary disease

(Chang et al., 2020)

Chronic cough is common in the community and causes significant morbidity. It is a prevalent problem in about 10% of the general populations worldwide (6) and poses a considerable socioeconomic burden and serious impairment to quality of life (QOL) (7) of children and their parents (8).

Children with chronic cough may experience physical pain, sleep disturbance, loss of school productivity, and social isolation for several months to years (9) Successful management requires a treatment program based on accurate diagnosis and understanding of the cough etiology.

Common pediatric etiologies are different from those in adults (10).This is not surprising as, while the physiology of the respiratory system in children and adults share similarities, there are also distinct differences between prepubertal children and adults that include maturational differences in airway, respiratory muscles and chest wall structure, sleep-related characteristics, respiratory reflexes and respiratory control (11).

➡️Clinical History and Examination:

The etiology of chronic cough in children can accurately be identified by observation, a careful history, and progressing to appropriate tests and therapeutic trials based on pointers obtained in the history (12). The impact of cough should be assessed either by recording simple measures such a cough scores out of 10 (Appendix) or by more detailed, validated measures of cough quality of life (QOL) (13,14).

➡️Etiology and Differential Diagnosis:

Cause	Remarks
Asthma	- Cough is commonly associated with recurrent wheezing - Asthma can be manifested only with cough and is then called cough-variant asthma or cough-dominant asthma. - A therapeutic trial of prednisolone should be offered if diagnoses of cough-predominant asthma or eosinophilic bronchitis are being considered (15).
Cystic fibrosis	- Clubbing and failure to thrive. - Universal newborn screening - Diagnosis is by measurement of sweat chloride concentration and genetic identification (16).
Primary ciliary dyskinesia	- Chronic wet cough - History of transient neonatal distress is common - Begins in infancy and persists (17). - Screening by measuring nitric oxide from nose - Diagnosis by electron microscopy and high-speed video-microscopy analysis (18).
Bronchiectasis	- Bronchiectasis can occurs with cystic fibrosis, primary ciliary dyskinesia, and in some patients with protracted bacterial bronchitis Bronchiectasis unrelated to chronic lung disease is also seen (19). -Diagnosis by radiology confirmed by computed tomography (20).
Pertussis (whooping cough)	- Frequent spasms of coughing followed by nausea or vomiting, cyanosis or apnea. like the barking cough - No history DPT vaccination (21).
Tracheomalacia or trachea-broncho-malacia	- Occasionally cause chronic cough - Barking quality - But persists during sleep, unlike habit cough. - Diagnosed only by bronchoscopy performed with light sedation so that dynamic movements can be visualized (22).
Protracted bacterial bronchitis (PBB)	Diagnosed clinically by: 1) Presence of continuous chronic (>4 weeks’ duration) wet or productive cough; 2) Absence of symptoms or signs (i.e. specific cough pointers) suggestive of other causes of wet or productive cough; and 3) Cough resolved following a 2–4-week course of an appropriate oral antibiotic. Diagnosed as PBB-micro by the contents of a broncho-alveolar lavage (23).
Habit cough (tic cough)	- Now labeled as somatic cough disorder (24). - Diagnosis should only be made after an extensive evaluation (25).
Postnasal drip syndrome/Upper airways cough syndrome (UACS)	UACS acting as a trigger for cough hypersensitivity although the mechanism remains obscure (26), (27).
Foreign body aspiration	- Causes localizing auscultatory findings. - History of sudden shocking (28).
Medications and Adverse Events	As a side effect of Angiotensin converting inhibitors (ACEI) (29), Asthma medications immediately after inhalation (30). Psychostimulant medications (e.g. Dextro-amphetamine resulting in new onset tics) (31).
Cardiac causes	Associated with specific manifestations (cough pointers)
Immunodeficiency	Two or more of these warning signs should alert clinician to the possibility of primary immunodeficiency and merit further assessment (32) (Appendix)
Gastro-esophageal reflux disease (GERD)	- GIT manifestations must be present - (GERD is not commonly identified as the cause of pediatric chronic cough (33).
Otogenic etiology Arnold's nerve reflex	Uncommon cause of chronic cough -The ears should always be examined for the presence of any foreign material (34).

➡️Investigations:

The investigation and therapeutic trials should include those for common cough-triggering conditions (rhinitis, rhinosinusitis, asthma, eosinophilic bronchitis, and GERD) as chest X-rays, spirometry (35), computed tomography (36) , flexible bronchoscopy and alveolar lavage (37). Other investigations include barium swallow, video fluoroscopic evaluation of swallowing, echocardiography, complex sleep polysomnography, immunological studies and nuclear medicine scans (5).

➡️Treatment of chronic cough in children:

All children with chronic cough should be carefully assessed, as chronic cough may be due to a serious underlying condition (e.g. inhaled foreign body). In addition to etiology-based management (38), it is prudent that children with chronic cough receive common management interventions as cessation of exposure to environmental tobacco smoke and other environmental pollutants (39).

The present clinical practice guideline aims to address major clinical questions regarding, practical diagnostic tools for specific and nonspecific chronic cough. Also, available therapeutic options for chronic cough in children are included.

➡️Purpose and Scope

These guidelines have been developed to standardize the delivery of services and to implement the guidance on the management (Diagnosis and Treatment) of chronic cough in children < 14 years.

It provides guidance to physicians, pediatricians primary Health Care (PHC) Physicians, family Practitioners, nurses & clinical pharmacist.

The guidelines aimed to optimizing the medical management of children with chronic cough.

Providing optimal pharmacotherapy to prevent or minimize adverse effects of therapy.