patient with cough
A cough is a sudden, and often repetitively occurring, protective reflex which helps to clear the large breathing passages from fluids, irritants, foreign particles and microbes. The cough reflex consists of three phases: an inhalation, a forced exhalation against a closed glottis, and a violent release of air from the lungs following opening of the glottis, usually accompanied by a distinctive sound.

Cough is the most common reason why patients seek medical attention. Acute cough caused by viral upper respiratory tract infection is usually self-limiting and seldom requires investigation. In contrast, chronic cough is challenging to manage as it often remains unexplained despite thorough investigation.


  1. Infective Disorders of Airway
  • Common cold
  • Sinusitis (post-nasal discharge)
  • Tonsillitis, Pharyngitis, Laryngitis
  • Laryngotracheobronchitis, Bronchiolitis
  • Pneumonia
  • Measles, whooping cough
  1. Inflammatory Disorders of Airway
  • Asthma and Loeffler’s syndrome, TPE
  • Inhalation of environmental irritants like tobacco, smoke dust.
  1. Pleural pathology
  • Pleural effusion
  • Empyema
  1. Suppurative Lung Disease
  • Bronchiectasis
  • Cystic fibrosis
  • Foreign body retained in bronchi
  • Lung abscess
  1. Anatomic Lesions
  • Congenital malformations, Sequestrated lobe
  • Bronchomalacia, Tumors
  • Tracheal stenosis, H-type TEF
  • Vascular ring
  • Tracheomalacia
  1. Irritative
  • Post-nasal discharge
  • Sinusitis
  • GERD
  • Irritation of EAM
  1. Psychogenic
  • Habitual cough
  1. Interstitial Lung Disease
  2. Compression of Airways
  • Lymph nodes
  • Retropharyngeal abscess
  • Mediastinal mass
  1. Non-pulmonary causes
  • CCF, pericardial effusion, constrictive pericarditis
  • Congenital heart diseases.
  1. Abdominal Causes
  • Diaphragmatic hernia, eventration of diaphragm, intra-abdominal masses
  • Massive ascites

a patient with cough

Life-threatening causes

  • Croup
  • Laryngeal edema
  • FB
  • Pertussis
  • Bronchiolitis
  • Asthma
  • Pneumonia
  • Toxic inhalation
  • CCF

Respiratory sounds

Sound Causes Character
Snoring Oropharyngeal obstruction Inspiratory, low-pitched irregular
Grunting By partial closure of the glottis Expiratory, occurs in hyaline membrane disease
Rattling Secretions in trachea/ bronchi Inspiratory, coarse
Stridor Obstruction larynx/ trachea An inspiratory sound may be associated with an expiratory component
Wheeze Lower airway obstruction Continuous musical sound expiratory in nature


  1. Acute /chronic
  • Considered to be chronic if > 2-3 weeks.
  • Significant overlap.
  1. Age of patient
  • Infancy- GERD, swallowing dysfunction, CCF associated with CHD.
  • Toddlers- RAD, passive smoking, ciliary dyskinesia.
  • Adolescents – infections (TB), RAD, psychogenic.
  1. Past history
  • URTI- Post-infectious, irritative, sinusitis.
  • H/o contact with TB.
  1. Associated symptoms
  • Fever, nasal discharge suggest infection.
  • Fever with chills or night sweats suggests TB.
  • Sputum production indicates bronchiectasis or other lower-airway pathology- with the headache or facial edema – sinusitis
  1. Quality of cough
  • Productive cough suggests lower airway infection, CF/bronchiectasis.
  • Barking seal-like cough is usually associated with croup.
  • Honking or brassy cough is typical in habitual or psychogenic cough.
  • Disease of the smaller airways (eg asthma or bronchiolitis)- high-pitched, “ tight” cough.
  1. Pattern of cough
  • Night time cough suggests Reactive Airway Disease.
  • With nighttime/early morning cough, consider sinusitis.
  • Paroxysmal with whoop – pertussis
  • Seasonal cough suggests an allergy.
  1. Sputum
  • Purulent- suppurative lung disease.
  • Mucoid – asthma (yellowish sputum in some cases due to  eosinophils).
  • Hemoptysis – bronchiectasis, MS, CF or FB.
  1. History of choking (i.e. Retained FB, etc.)
  1. FTT/ severe undernutrition
  2. CF, immunodeficiency.
  3. Chronic cough– TB, bronchiectasis, pertussis, CF, severe chronic asthma or immunodeficiency syndrome.
  4. Immunization history DPT, measles, BCG

Physical Examination

  1. General appearance:-
  • Evidence of FTT – consider CF, immunodeficiency.
  • Pallor – severe anemia
  • Cyanosis – hypoxemia/heart disease.
  • Subconjunctival hemorrhage – pertussis
  • Tachypnea, use of accessory muscle – respiratory distress.
  • Grunting, nasal flaring, head nodding, wheezing
  • Stridor, in combination with cough, generally indicates obstruction at the level of larynx or trachea.
  • JVP – raised in CCF.
  1. Vital signs:-
  • Fever – infective pathology.
  • Pulse – tachycardia–CCF, fever, distress.
  • RR- to be counted for 1 minute when the child is calm.
  1. Clubbing:-
  • Bronchiectasis, lung abscess, cystic fibrosis.
  1. ENT Examination:-
  • Nose – nasal discharge – blood stained/ serous/ purulent; DNS.
  • Polyps – allergy.
  • Pharynx – congested/ grey membrane.
  • Tonsils – enlargement/ congestion/pus points.
  • Ear – discharge (ASOM), retraction of TM.
  1. Signs of atopic disease:-
  • Eczema, transverse nasal crease, rhinitis, mucosal cobblestoning, injected conjunctivae – consider RAD, allergy.
  1. Sinusitis: – Periorbital edema, sinus tenderness, purulent posterior pharyngeal drainage, halitosis

System Examination

Respiratory system:-

  • Intercostal or subcostal indrawing.
  • Intercostal fullness (pleural effusion, empyema) or crowding of ribs (collapse, fibrosis).
  • Decreased movement of either hemithorax.
  • Suprasternal recessions – suggestive of narrowing or obstruction of upper airways (laryngeal diphtheria, acute laryngotracheobronchitis, laryngeal/tracheal FB and angioneurotic edema).
  • The position of the trachea (trail sign).


  • Feel for abnormal vibrations – rhonchi, friction rub, crackles, crepitus (subcutaneous emphysema- pertussis).
  • Vocal fremitus.
  • Expansion of hemithorax.


  • Area of dullness- pleural effusion (shifting dullness), empyema, consolidation.
  • Hyper-resonant – pneumothorax.
  • Percuss for upper margin of liver dullness.


  • Compare air entry B/L.
  • Bronchial breath sounds.
  • Added sounds – crackles, rhonchi, pleural friction rub.
  • Vocal resonance
  • Absent/ decreased – pleural effusion, atelectasis.
  • Increased – consolidation, atelectasis with patent bronchus.

Never forget to examine:

  • Cardiovascular System
  • Abdomen


  1. Complete blood count
  • Hb -anemia
  • Total and differential count- infections.
  • Eosinophilia – TPE, Loeffler’s syndrome.
  1. Sputum
  • AFB
  • Eosinophils suggest an asthmatic process or hypersensitivity process of the lung.
  • PMN cells suggest infection.
  • Lipid laden macrophages- suggest recurrent aspiration.
  • Routine or special cultures based on likely pathogens.
  1. Pulse Oximetry
  • For bedside evaluation/monitoring hypoxia.
  1. Blood C/S
  • Important in any infective pathology.
  1. ABG
  • Estimation of partial pressures of O2 and CO2 in blood along with blood PH is used for making the diagnosis of respiratory failure or metabolic acidosis (sepsis/shock)
  1. X- rays
  • CXR – especially in heart diseases, pneumonia not resolving with treatment, pleural effusion.

-Infiltrates may suggest pneumonia, bronchiolitis, pneumonitis, TB, CF, bronchiectasis.
-Volume loss may be seen with foreign body aspiration.
-Hyperinflation suggests RAD or CF.
-Mediastinal nodes may indicate infection (esp. TB, fungus) or malignancy.

  • Sinus films – sinusitis.
  • Lateral neck X-rays – acute epiglottitis, retropharyngeal abscess.
  • Barium swallow –TEF, GERD.
  1. CT – Scan
  • Bronchiectasis (HRCT).
  • Lymph nodes, pleural pathologies.
  1. Pulmonary Function Tests
  • To diagnose and follow the course of chronic respiratory illness.
  1. Immune workup
  • Ig levels
  • HIV testing
  1. Bronchoscopy:-
  • To remove a foreign body or obtain samples (BAL).

Please click on share to help us grow!