Cough in children

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] Associate Editor(s)-in-Chief: Marufa Marium, M.B.B.S[2]

Synonyms and keywords: Cough in kids

Overview[edit | edit source]

Cough is a common complaint of the pediatric population of the outpatient department. It is a natural reflex by which foreign and infectious particles are cleared through an involuntary expulsive force of air by the dynamic mechanism of respiratory airways. The word 'Cough' is derived from the 14th century Dutch word 'Kochen' and the high middle German word 'Kuchen'. Cough is classified under several categories. For example, duration of the complaint, nature or quality, anatomical location, etiology and grades of coughs. Stimulation to cough receptors provokes sensations of coughing through the afferent pathway via the vagus nerve, central respiratory centers in the upper pons and medulla, and efferent pathways via the phrenic and vagus branches. Differential diagnoses of cough are evaluated through identifying specific etiology, presenting symptoms, detailed history and findings of physical examination, laboratory, and imaging investigations. Some of the causes are emergently managed to reduce the mortality of a child.The mainstay of therapy for cough is supportive. Antihistamine, antitussive medications and nasal decongestant are provided for alleviating symptoms of acute cough. Allergic conditions are treated with steroids.

Historical Perspective[edit | edit source]

• The word cough was first derived from the middle English word 'Coughen' or old English 'Cohhian' which was primarily composed of the middle Dutch 'Kochen' and the high middle German 'Kuchen', in early 14th century.

Classification[edit | edit source]

• Cough in children may be classified or defined according to the duration of presenting complaints, quality and sound, and causes of cough into several groups.^[1]:
• 1 Duration of Presenting complaints: According to the duration of cough, it can be sub-classified into three categories:
  • Acute: < 3 weeks.
  • Subacute: 3 to 8 weeks.
  • Chronic: > 8 weeks.

• 2. Nature or quality and sounds: According to the quality and sound, the cough can be sub-classified in to following categories:
  • Dry or Hacking or Nonproductive.
  • Wet or productive cough.
  • Staccato or short repetitive cough.
  • Whooping or paroxysmal violent or spasmodic cough.
  • Barking cough: Brassy barking or Honking barking.
  • Phlegmy cough.
  • Burning cough.

• 3. Causes of Cough: Based on the causes, a cough is subdivided into following three subgroups:
  • Specific cough.
  • Nonspecific cough.
  • Expected cough or Normal cough.

• 4. Anatomic classification on the causes of a cough: A cough can be produced from different anatomical locations. For example:
  • Nose and Paranasal sinuses.
  • Pharynx.
  • Larynx.
  • Trachea and Bronchi.
  • Pulmonary parenchyma.
  • Pleura.
  • Mediastinum.
  • Heart and blood vessels.
  • External ear and Tympanic membrane.
  • Esophagus.

• 5. Grades of cough: Cough can be graded into four main sub categories:^[2]
  • Eutussia or Normal.
  • Hypertussia or Sensitized.
  • Hypotussia or Desensitized.
  • Dystussia or Pathological.
  • Atussia or Absent.

Cough in children can also be classified under infectious (Bacterial, Viral, fungal, Parasitic) or non-infectious categories broadly.

Pathophysiology[edit | edit source]

• A cough is a natural innate primitive reflex that helps in mucocilliary clearance of foreign particles and secretions from respiratory tracts. It is also a defense mechanism protecting the respiratory airways from aspiration of pathogens, particulates and secretions. A complex arc comprised of neuro-respiratory pathways helps in initiating the cough reflex.^[3]

• On gross pathology, bloody, serous , mucoid, rusty, pink frothy, and purulent are characteristic findings of sputum produced by coughing.
• On microscopic histopathological analysis, pathogens, RBCs, leukocytes, epithelial cells are characteristic findings of sputum produced by coughing.

Causes[edit | edit source]

Causes of cough in children according to duration^[4][5][6]:

According to quality and sound of cough in children, the causes can be classified according to the following chart:

Based on anatomical location the causes of cough in children can be demonstrated in the following chart:

Differentiating Cough from other Diseases[edit | edit source]

*Apnea

Epidemiology and Demographics[edit | edit source]

• A cough is one of the most common presenting symptoms of children in the outpatient department.
• Ninety percent of acute coughs in children are resolved within three weeks. The prevalence of chronic cough in children is approximately 5% to 10% in the USA according to the American Academy of Pediatrics.

Age[edit | edit source]

• Cough is more commonly observed among children under 5 years of age.^[41]

Gender[edit | edit source]

• Boys are more commonly affected with cough than girls.^[42]

Race[edit | edit source]

• There are racial predispositions for certain causes of cough in children. Asthma is predominant in Blacks and American Indians or Alaska natives while Cystic fibrosis, Wegener's granulomatosis more frequently affect Caucasians according to the American Lung Association.

Risk Factors[edit | edit source]

• Common risk factors in the development of a cough in children are:^[43][44]
  • Preterm birth and delivery by caesarian section.
  • Respiratory Distress Syndrome.
  • Congenital Heart Disease.
  • Age less than 1 year.
  • Maternal Influenza vaccination.
  • Malnutrition.
  • Secondary exposure to tobacco smoke.
  • Air pollutants, Mold, Inadequate ventilation.
  • Immunodeficiencies.
  • Daycare attendance.
  • History of Atopy.
  • Household pets.
  • Low socioeconomic status.

Natural History, Complications and Prognosis[edit | edit source]

• The majority of patients with acute cough have recovery within three weeks in 90% of cases. Some cases are progressed to subacute and chronic phases. Chronic cough lasts more than eight weeks whereas recurrent cough can affect a child for more than two years with 1-2 weeks duration in each episodes.^[45]
• Early clinical features include frequent episodes of coughing, runny nose, sneezing, low grade fever, sore throat, night sweats, arching back, irritability, failure to thrive, fussiness, and a choking sensation(foreign body impaction).^[46]
• If left untreated, acute cough can cause following the complications in children:^[4][45]
  • Otitis Media
  • Rash
  • Vomiting
  • Diarrhea
  • Bronchitis
  • Pneumonia
• Chronic cough can progress to^[47]-
  • Inability to sleep
  • Bronchospasm
  • Dizziness/ Syncope
  • Pneumothorax
  • Pneumomediastinum
• Rib fracture

• Prognosis is generally excellent and efficiently treatable in most of the etiology of cough in children.

Diagnosis[edit | edit source]

Diagnostic Criteria[edit | edit source]

• Diagnosis of causes of a cough is made after a detailed history, presenting complaints and physical examination and laboratory findings in some cases. Cough can be classified according to:^[48]
  • Duration.
  • Nature or quality of cough.
  • Etiology.
  • Anatomic location.
  • Grade.

A detailed history focusing on onset of disease, factors worsening the episodes, time of worsening, alleviating factors, amount of work to breathe, presence of shortness of breathing, relation with vomiting, food intake, posture, presence of blood, systemic findings (fever, weight loss, hypotension, syncope, vertigo, dizziness, failure to thrive), episodes of choking, household socioeconomic status, family history, vaccination history, drug abuse and smoking in family members, atopy, antenatal, perinatal, postnatal, birth history, developmental history, feeding history.

The following signs are alarming which need further emergent evaluation by the physician:

• Cyanosis or hypoxemia or hypoxia
• Respiratory distress
• Stridor
• Toxic appearance
• Weight loss

Symptoms[edit | edit source]

• Cough may be associated with the following depending upon the cause:

• Breathlessness and episodes of coughing
• Sneezing
• Fever
• Sore Throat
• Night Sweats
• Arching Back
• Irritability
• Failure to thrive
• Fussiness
• Choking sensation(Foreign body impaction)
• Chills and Rigor
• Wheezing
• Headache, myalgia, fatigue

Physical Examination[edit | edit source]

• Patients with cough are usually restless, irritable, fussy. Children with severe respiratory distress usually are toxic and cyanotic in appearance. Presence of grunting, nasal flaring, intercostal or subcostal retraction or accessory muscle usage needs prompt evaluation.^[46][48]
• Physical examination may be remarkable for:

• Vital signs: Documentation according to patient's age
  • Blood pressure
  • Temperature
  • Respiratory rate
  • Heart rate

• • Growth charts and developmental milestones: weight, height, length, occipitofrontal circumference
• General Appearance: Level of consciousness, Cyanosis, Distressed or ill-appearing, hydration and nutritional status.
• Skin: Turgor, color, texture, rashes or any other abnormal findings.
• Lymphatics: Lymphadenopathy, location, number and size, consistency, adherence to underlying structures.
• Head: Size, shape, fontanelle, overlapping suture, scalp, hair.
• Eyes: Lacrimation, redness, irritation, conjunctival injection, periorbital redness.
• Ears: Position of ears along with external auditory canal, tympanic membrane visualization.
• Nose: Any deviation of nasal septum, normal or hypertrophied inferior turbinate, nasal polyps and congestion, nasal discharge, tenderness over sinus point.
• Mouth and throat: Look for any associated abnormality
  • Lips: Color, mucosal abnormality and congenital lesions.
  • Buccal mucosa: Hydration, Color, Presence of anomaly.
  • Tongue and teeth and gum: Developmental anomaly, Color, papillae.
  • Palate: Anomaly, arch.
  • Tonsils: Color, size, any membrane, calcification and exudates.
  • Posterior pharyngeal wall: Color, appearance.
  • Gag reflex: Intact or not.
• Neck: Thyroid, trachea position and examination, any cystic or nodular masses, presence of nuchal rigidity.
• Respiratory:
  • Inspection: Breathing pattern (abdominal and periodic), respiratory rate, accessory muscle usage, chest wall shape.
  • Auscultation: breath sound symmetry, vesicular, bronchial, rales, rhonchi, wheezes, stridor.
  • Percussion: resonance, hyper resonance and dull.
  • Palpation: trachea position, tactile fremitus.
• Cardiovascular: rhythm, murmur, any radiation of sound, pulse in both extremities.
• Gastrointestinal: Shape of abdomen, Umbilicus, Bowel sounds, Palpation to evaluate any organomegaly or masses or rebound guarding.
• Musculoskeletal: Aching back, scoliosis, lordosis, kyphoscoliosis, swelling and tenderness in any muscles, joint, clubbing, edema, deformity of extremities, gait and posture, any sign for hip dysplasia.
• CNS: Primitive reflex, superficial and deep tendon reflex, strength and tone of muscles, cranial nerve examination.
• Genitourinary: Presence of external genitalia deformity , hydrocele, cryptorchidism or hernia.

Laboratory Findings[edit | edit source]

• There are no specific laboratory findings associated with cough. Laboratory tests are done to differentiate the causes of cough in children^[47].
• Complete Blood Count
• Arterial blood gas analysis
• Culture of nasopharyngeal swab and broncho alveolar lavage
• Gross and microscopic analysis and culture of sputum
• AFB testing and tuberculosis screening
• Allergy test
• Serum Immunoglobulins, autoantibodies
• Sweat test
• Exhaled nitric oxide test
• Esophageal pH
• Serology for Pertusis, CMV, Chlamydia, HIV.

Electrocardiogram[edit | edit source]

An ECG may not be helpful in the diagnosis of congenital heart disease, myocarditis, valvular heart disease, in children.

X-ray[edit | edit source]

Anterior/posterior view, lateral Chest and neck x-ray may be helpful in the diagnosis of causes of cough in children for: Pneumonia, Croup, Bronchitis, Epiglottitis, Foreign body impaction etc. X-ray of paranasal sinuses helps in diagnosis of sinusitis, deviated nasal septum.

Echocardiography or Ultrasound[edit | edit source]

Echocardiography/ultrasound may be helpful in the diagnosis of causes of cough in children. Echocardiographic findings aide in the diagnosis of congenital heart disease, whereas USG findings can help in evaluating complications like peritonsillar abscess, retropharyngeal abscess promptly.

CT scan[edit | edit source]

The High resolution CT is used for diagnosing causes of chronic cough in children such as bronchiectasis. Sometimes it helps in identifying congenital heart and lung anomalies.

MRI[edit | edit source]

A Chest MRI may be helpful in the diagnosis of the dynamic function of airways disease.^[49]. MRI can provide detailed findings of perfusion, ventilation mechanism of lungs and diaphragm. It can show oxygen enhancement, congenital anomalies too.

Other Imaging Findings[edit | edit source]

Other imaging techniques are used to evaluate causes of cough in children.

• Flexible Bronchoscopy
• Barium esophagram.
• Angiography

Other Diagnostic Studies[edit | edit source]

Other investigations done to rule out differential diagnosis of cough in children are:

• Spirometry for evaluating pulmonary function test.
• Bronchodilator provocation test.
• Ciliary function test.
• Genetic analysis for CFTR mutation, Primary ciliary dyskinesia etc.
• Video fluoroscopic or endoscopic swallow evaluation.
• Environmental assessment.

Treatment[edit | edit source]

Medical Therapy[edit | edit source]

• The mainstay of therapy for cough is supportive. Management of acute and chronic cough in children can be provided in the following sequences:^{[1][50][51][52]}
• Identification of etiology of cough and emergently manage the emergency condition such as foreign body impaction, severe respiratory distress, apnea with maintenance of airways, breathing, circulation.
• General measures with adequate hydration, nasal airway clearance with normal saline, reducing fever with antipyretics are done to give comfort to the child.
• Medical management:
  • Antihistamine, antitussive medications and nasal decongestant are provided for alleviating symptoms of acute cough. Allergic conditions are treated with steroids.
  • Bronchodilators (Ipratropium bromide, Albuterol, Salmeterol, Salbutamol), Antibiotic (Amoxicillin/Clavulanate, Cephalosporins, Respiratory fluoroquinolones, Antiviral, Antifungal, Antiparasitic) are used according to evidence-based management of particular causes of cough in children.

Surgery[edit | edit source]

• Some surgical procedures are performed for patients with Tonsillitis, adenoid hypertrophy, severe cases of laryngomalacia, tracheoesophageal fistula, congenital heart disease, complications of any disease or trauma in ear, nose, sinuses, pharynx, larynx, trachea, bronchus, lungs, and ribs.

Prevention[edit | edit source]

• Effective measures for the primary prevention of cough include:
  • Caregivers should be given health education on pros and cons of vaccination, alarming features of cough.
  • Physical hygiene including airways of an infant or a child should be maintained to prevent complications.
  • Head should be raised to prevent irritations in throat.
  • Humidified air will help clearing the sputum easily.
  • Adequate hydration to prevent formation of dry sputum.
  • Avoidance of triggers in case of atopic patient.
  • Nutritional balance should be maintained for rebooting the immunity.

References[edit | edit source]