JC121 (Paediatrics) - Cough in children Flashcards
Physiology of cough reflex
Cough reflex protects the airway following inhalation of foreign material (food, secretions etc.):
Stimuli: Mechanical, chemical, thermal, inflammation
Cough receptors located within the epithelium of the pharynx, larynx, trachea, major bronchi become stimulated:
Local reaction:
Local mediators: histamine, prostaglandins, leukotrienes
Local bronchoconstriction
Afferent fibres from vagus nerve to cough centre in upper brainstem
Efferent fibres from vagus nerve and spinal cord to larynx, diaphragm, abdominal muscles cough
Respiratory and non-respiratory causes of cough
Respiratory Upper respiratory tract infection Postnasal drip syndrome (upper airway cough syndrome) Asthma Aspiration Pneumonia/pneumonitis Bronchiectasis
Non-respiratory Heart failure Gastroesophageal reflux ACE inhibitor (S/E) Psychogenic/habit cough
Outline history taking questions for cough
Patient background:
- Age: type of organism, respiratory problem
- Previous health: CAI or HAI
- Immune status: Opportunistic infections
- Neurological: aspiration pneumonia
- Atopy: asthma, post-nasal drip
- Living status: CAI from institutions
Cough characteristics: Dry vs productive, bloody or not, barking/ brassy/ wheezing/ paroxysmal
Duration of cough
Triggering factors
Associated constitutional symptoms
Causes of cough in infancy
Aspiration
Allergy: reactive airway (not dx asthma until 2 years old)
Infections: Chlamydia Pertussis Tuberculosis Post- respiratory syncytial virus
Structural Congenital malformation:
Laryngotracheomalacia/ bronchomalacia
Vascular compression (ring/ sling innominate artery)
Passive smoking
Congenital heart disease
Causes of cough in early childhood
Aspiration
Asthma (>2 years old)
Infections: Viral Tuberculosis Mycoplasma Fungal
Bronchiectasis:
Immunodeficiency
Cystic fibrosis
Post-infectious
Sinusitis
Causes of cough in late childhood/ adolescence
Aspiration
Asthma
Infections: Viral Tuberculosis Mycoplasma Fungal
Bronchiectasis:
Immunodeficiency
Cystic fibrosis
Post-infectious
Sinusitis*
Mediastinal tumor*
Active or passive smoking*
Psychogenic cough*
Types of productive cough
Mucus: Normally produced by goblet cells and submucosal glands, increase in volume during illness
Exudates: Protein-rich fluid leaked from capillaries in alveoli due to inflammatory response (usually due to infection)
Acute cough
Define time limit
Causes
= recent onset of cough lasting <3 weeks
Causes of acute cough: URTI: mostly viral infection LRTI: Viral or bacterial infection Exacerbation of pre-existing disease: - Asthma (acute attack) - Bronchiectasis (flare) - Upper airway cough syndrome
List viral and bacterial pathogens that cause acute cough
Viral:
Influenza, respiratory syncytial virus, parainfluenza, adenovirus, rhinovirus, human coronavirus, human metapneumovirus (hMPV), bocavirus
Bacterial: Streptococcus pneumoniae Haemophilus influenzae Moraxella catarrhalis Pseudomonas (if immunocompromised) Chlamydia (if neonate)
Outline P/E for acute cough
A. Vital signs, temperature (fever)
B. Respiratory distress: RR, use of accessory muscles, dyspnea, cyanosis
C. Chest exam: deformity, percussion, auscultation (wheeze, crepitations, rhonchi)
D. Associated finding:
Skin rash, eczema
Lymph nodes, tonsils
Rhinorrhea
Define respiratory rate for tachypnea in neonates < 2 months, 2-12 months and >1 year old
tachypnea in children:
>60 for <2m,
>50 for 2-12m,
>40 for >1 yr
Child presents with acute cough that worsens when laying down
The cough is triggered by pollen at certain seasons
Most likely dx
Post-nasal drip from allergic rhinitis
Child presents with cough and nasal discharge, sore throat and fever
Most likely Dx
Acute upper respiratory tract infection
Most likely viral infection
Child presents with hoarseness, acute cough, high fever, and stridor
Most likely ddx
Viral croup
Recurrent spasmodic croup
Bacterial tracheitis
Child presents with fever, tachypnea, increase work of breathing, productive cough and some wheezing
Most likely dx
Lower respiratory tract illness:
Acute bronchiolitis:
Typically RSV, hMPV
Present with wheezing due to inflammatory exudates in small airways
+/- crepitations
Pneumonia (viral, bacterial)
Asthma (should not present with crepitations, just wheeze)
Child with acute cough presents with finger clubbing, failure to thrive and some chest deformity
Most likely Dx
Acute exacerbation of a chronic respiratory disorder e.g. bronchiectasis
Clinical features of allergic rhinitis/ reactive airway/ asthma in a child
Seasonal and diurnal variation
Posture (more cough when lay down worsen postnasal drip)
Triggers (dust, pollutant, pollen etc.)
Association with rhinitis
‘Clearing of throat’ (postnasal drip)
Clinical features of acute URTI in children
Coryzal symptoms (common cold: cough, nasal discharge)
Sore throat
Fever
Clinical presentation of acute airway obstruction in children e.g. croup, epiglottitis
Stridor (upper airway obstruction)
‘Barking’/ brassy/ ‘croupy cough’
Hoarseness
+/- fever
Clinical features of LRTI in children
Fever
Tachypnea
Respiratory distress with increased work of breathing
(Productive cough)
Chest signs (crepitations/ wheeze/ rhonchi)
Clinical features of chronic respiratory disorder in children
Failure to thrive
Finger clubbing
Chest deformity
Features of atopy
First-line investigations for acute cough in children
Not needed in most children with simple URTI
CXR - indications:
- LRTI
- Relentless progressive cough past 2 weeks
- Hemoptysis
Microbiological workup:
- CBC and differentials (bacterial pneumonia)
- Nasopharyngeal aspirates for common viruses, Mycoplasma
- Sputum for Gram stain and culture
- Blood culture e.g. pneumococcus
Definition of pediatric (<15yrs) chronic cough
American College of Chest Physician Guideline:
daily cough lasting for > 4 weeks
British Thoracic Society
Cough lasting >8 weeks
Recognizes a ‘grey’ area of ‘subacute cough’ between 2-8 weeks
Outline history taking for chronic cough in children
HPI:
- Onset of cough: e.g. from neonatal period or later
- Start of cough: after choking? with URTI?
- Quality of cough
- Trigger of cough: Exercise/ cold air, nocturnal, feeding
Ddx underlying cause:
- Feeding difficulties
- Chest pain-related
- Neurodevelopmental abnormality (cerebral palsy)
- Recurrent pneumonia
Ddx causes of chronic cough depending on onset and start/ first episode
Neonatal onset Aspiration (tracheoesophageal fistula) Congenital malformation Cystic fibrosis (inherited) Primary ciliary dyskinesia (inherited)
With choking: inhaled foreign body
With URTI: Post-viral cough
Ddx causes of chronic cough by quality of cough ***
Dry cough: Mycoplasma, asthma, viral infection
Dry/ repetitive/ disappears with sleep/ Honking cough: Psychogenic/ habit cough
Productive (Moist/ wet) - Chronic suppurative lung disease/ pneumonia
Hemoptysis/ blood-stained: TB, Bronchiectasis, AV malformation, Pneumonia, Excoriated airway
Paroxysmal spasmodic cough: Pertussis, Parapertussis, Mycoplasma, Viral
Barking/ brassy cough: Croup, Tracheomalacia, Habit cough
Staccato cough: Chlamydia
Ddx dry vs productive chronic cough in children
Dry:
Mycoplasma (1st week)
Asthma
Viral (e.g. coronavirus)
Productive:
Chronic suppurative lung disease (e.g. bronchiectasis)
Pneumonia
Ddx hemoptysis/ blood stained chronic cough in children
TB (in adolescents) Bronchiectasis AV malformation (in younger children) Pneumonia Excoriated airway
Ddx Paroxysmal spasmodic chronic cough in children
Pertussis, parapertussis
Mycoplasma
Virus
Ddx causes of chronic cough due to trigger by exercise, cold air, nocturnal, feeding
Exercise, cold air = Asthma/ reactive airway
Nocturnal (2-3am, early morning)
Upper/ lower respiratory allergy
Sinusitis
Feeding = Recurrent aspiration
Ddx chronic cough with feeding difficulties in children
Serious systemic illness (including pulmonary)
Aspiration
Neurodevelopmental abnormality (cerebral palsy)
Ddx chronic cough with chest pain in children
Arrhythmia
Asthma, increased respiratory distress (parenchymal disease)
Ddx recurrent pneumonia in children
Immunodeficiency
Congenital lung abnormalities
H-type tracheoesophageal fistula
Outline P/E for chronic cough in children ***
Growth: Failure to thrive
Respiratory distress: Hypoxia/ cyanosis
Finger clubbing: chronic suppurative lung diseases
Upper respiratory tract: Sinusitis, allergic rhinitis
- Sinusitis: facial tenderness, persistent purulent nasal discharge
- Allergic sinusitis: nasal obstruction/ discharge
Lower respiratory tract: Chronic lung disease
- Chest wall deformities: Harrison sulcus, Pectus carinatum, Barrel chest
- Hyperresonance
- Creptitation and breath sounds
Cardiac: Murmur, heart failure
Skin: Eczema
Causes of non-specific chronic cough in children
(dry cough in absence of an identifiable respiratory disease of known etiology)
Management of non-specific cough
Causes:
Post-viral
Another episode of acute infection
Others: foreign body, asthma, GERD (reflux) etc.
Evaluation: conservative, non-interventional
Avoid Tobacco smoke, other pollutants
Child’s activity and thriving
First-line investigations for chronic cough in child
- Workup bronchiectasis, TB, Primary immunodeficiency, Chronic pneumonia, structural lesions in bronchi
List:
- CXR
- Spirometry tests: obstructive or restrictive pattern
- CBC with differentials (immunodeficiencies, infections)
Microbiological workup:
- Test for TB (Mantoux test or purified protein derivative test or interferon-based test
- Sputum/ gastric aspirate for AFB stain and culture, TB PCR, routine culture and CST
Radiological:
- HRCT/ MRI
DDx:
- Cilia study for primary ciliary dyskinesia
- 24h esophageal pH study - Reflux
- VFSS - aspiration
- Bronchoscopy - intraluminal lesions
Treatment for viral URTI
most viral infection, including: bronchitis, viral pneumonia
- No specific antivirals
- Supportive
Influenza:
- Antivirals available: oseltamivir, zanamivir
Treatment of CAP in children
Community acquired pneumonia
Streptococcus pneumoniae
Haemophilus influenzae
Moraxella catarrhalis
Augmentin
Treatment of atypical pneumonia in children
Commonly Mycoplasma pneumoniae, others: Legionella and Chlamydia
Quinolone
Doxycycline (avoid in <8yo because permanent teeth discoloration)
Clarithromycin (macrolide resistance 30%)
Treatment of pseudomonas and S. aureus respiratory infection in children
Pseudomonas
Extended-spectrum penicillins (e.g. piperacillin-
tazobactam)
3rd/ 4th generation cephalosporins (e.g. ceftazidime)
Carbapenems (e.g. meropenem)
Aminoglycosides (e.g. amikacin)
Fluoroquinolones (e.g. levofloxacin) = only oral
available
Staphylococcus aureus:
Vancomycin
Symptomatic treatment options for cough in children
Antihistamine: diphenhydramine, Chlorpheniramine
Antipyretic, analgesic: paracetamol, ibuprofen
Antitussives/Cough suppressants: Codeine, Dextromethorphan, Hydrocodone
Expectorant: Guaifenesin
Nasal decongestants: Ephedrine, Phenylephrine, Pseudoephedrine, Phenylpropanolamine
Cough relief:
- Oral hydration with warm liquid
- Honey in water
Which symptomatic relief agents are not recommended for treating cough in children
Antihistamines: no effect, not recommended
Expectorants, mucolytics: No recommendation for expectorants, limited recommendation for mucolytics
Cough suppressants: Definitely NOT recommend codeine or hydrocodone-containing cough suppressants
Codeine
- Reasons for contraindicated use in children
- S/E
Codeine: - Narcotic with addictive potential - Dose-related toxicity: Respiratory depression Narcosis, somnolence Ataxia Miosis Vomiting, rash Swelling Itching
Dextromethorphan
- Reasons for contraindicated use in children
- S/E
Nonaddictive but abused by teenagers
Dose-related S/E:
Ingesting huge doses = bizarre behaviour
CNS depression
Honey as cough relief for children
- Recommendation on use
- Contraindications
Recommendation: Modest beneficial effect on nocturnal cough (more effective than placebo or diphenhydramine)
Contraindication: risk of botulism (food poisoning)
