A Child With Cough Acute And Chronic Cough In Children
Acute cough in children lasts less than 4 weeks and is usually infectious, while chronic cough persists beyond 4 weeks and requires evaluation for underlying causes such as asthma, protracted bacterial bronchitis, or foreign body aspiration.
A Child with Cough: Acute and Chronic Cough in Children
The big idea: Cough in children is overwhelmingly common, mostly benign and self-limiting (viral URTI), but the same symptom can be a red flag for serious underlying disease—from foreign body aspiration to bronchiectasis to cystic fibrosis. The clinician's job is to use a structured history and physical examination to distinguish the child who needs nothing more than reassurance from the child who needs urgent investigation and treatment. This lecture also hammers home a critical public-health/ethical message: OTC cough suppressants in young children are ineffective, potentially dangerous, and should not be prescribed. [1]
How this fits into exams: Paediatric cough questions appear as MCQs (choose the most relevant history question, identify the diagnosis from cough character), SAQs (list differential diagnoses for acute/chronic cough, discuss investigation approach), and minicases (clinical vignette with cough + additional features). Past papers consistently test the ability to (a) discriminate acute from chronic, (b) identify "specific cough pointers," (c) know the age-based differential, and (d) counsel against OTC cough medicines.
Learning objectives (from Block C learning points): [2]
- Understand the cough reflex arc and its protective role
- Systematically approach a child with acute and chronic cough (Who/What/How/When)
- Differentiate acute vs chronic cough with correct thresholds
- Recognize specific cough pointers (red flags) that demand investigation
- Know the evidence against OTC cough suppressants in children
- Treat the cause, not the symptom
1. The Cough Reflex — First Principles
Cough is under both voluntary and involuntary control. It clears the airways of secretions and is the primary mechanism for secretion removal when respiratory cilia are damaged by inflammation. [1]
Cough is a protective reflex. When mucociliary clearance is intact, the mucociliary escalator carries debris and mucus upward. When the cilia are damaged (by viral infection, smoke, chronic inflammation), cough takes over as the backup clearance mechanism. This is why suppressing cough in a child with pneumonia or bronchiectasis can be actively harmful—you remove the only remaining defense against secretion retention. [1]
Cough receptors are located within the epithelium of the pharynx, larynx, trachea, and major bronchi. [1]
| Location | Stimulus type | Clinical relevance |
|---|---|---|
| Pharynx, larynx, trachea, major bronchi | Mechanical, chemical, thermal | Main site — explains cough from URI, croup, foreign body |
| Pharynx | Mechanical (postnasal drip) | Upper airway cough syndrome |
| Paranasal sinuses | Inflammatory mediators | Sinusitis causing chronic cough |
| Stomach / oesophagus | Acid, distension | GERD-associated cough |
| External auditory canal (EAC) | Mechanical (Arnold nerve branch of vagus) | Ear wax, otitis can trigger cough |
Key exam point: The source of persistent cough may not be in the lungs — cough receptors are also in the pharynx, paranasal sinuses, stomach, and EAC. [1][2] This explains why GERD, sinusitis, and even cerumen impaction can cause chronic cough.
Afferent fibres from the vagus nerve travel to the cough centre in the upper brainstem; efferent fibres from the vagus nerve and spinal cord go to the larynx, diaphragm, and abdominal muscles to produce a cough. [1]
Stimuli → cough receptors → afferent vagus → medullary cough centre (upper brainstem) → efferent via vagus + spinal motor nerves → larynx (glottic closure), diaphragm + abdominal muscles (explosive expiration) → cough
Higher cortical control allows cough inhibition and voluntary cough. [1]
This explains psychogenic/habit cough: a child can voluntarily produce a cough and can also suppress it (notably, habit cough disappears during sleep because cortical override is absent). [1]
Cough receptors are stimulated by local mediators: histamine, prostaglandins, leukotrienes, and by local bronchoconstriction. [1]
This is why asthma causes cough — bronchoconstriction and airway inflammation release these mediators, stimulating cough receptors even if the child does not wheeze audibly (the concept of cough-variant asthma).
Causes of cough in children may be different from adults. [1]
| Respiratory causes | Non-respiratory causes |
|---|---|
| Upper respiratory tract infection | Heart failure |
| Postnasal drip syndrome (Upper airway cough syndrome) | Gastroesophageal reflux |
| Asthma | ACE inhibitor |
| Aspiration | Psychogenic/habit cough |
| Pneumonia/pneumonitis | |
| Bronchiectasis |
Exam Trap
In adults, the classic triad of chronic cough is (1) upper airway cough syndrome/postnasal drip, (2) asthma, (3) GERD. In children, the differential is broader and age-dependent — always think of congenital causes (e.g., tracheoesophageal fistula, vascular ring) in neonates/infants and foreign body aspiration in toddlers.
3. Clinical Approach: The "Who/What/How/When" Framework
The lecture organizes history-taking into four domains: Who, What, How, When. [1] This is a systematic method to narrow the differential.
Age, previously healthy?, immunocompromised/HIV infected?, neurologically impaired?, atopic?, living at home or institution? [1]
| Feature | Why it matters | Diagnostic implications |
|---|---|---|
| Age | Different organisms and conditions dominate at different ages | Neonatal cough → congenital malformation, Chlamydia; Toddler → foreign body; School-age → Mycoplasma, psychogenic |
| Previously healthy | Rules out chronic underlying condition | |
| Immunocompromised | Opportunistic organisms (Pseudomonas, Pneumocystis, fungi) | Must have lower threshold for investigation |
| Neurologically impaired | Swallowing incoordination → aspiration pneumonia | The 2024 MCQ (Q93) tests this directly — in a child with CP and chronic cough, choking on feeding (aspiration) is the most relevant history [8] |
| Atopic | Asthma, allergic rhinitis → postnasal drip | Family and personal history of atopy |
| Institutional vs. home | Community-acquired vs. hospital-acquired organisms | Institutional → TB, resistant organisms |
3.2 WHAT Is the Cough Like?
Dry? Productive? Blood-stained? Barking? Brassy? Wheezy? Paroxysmal? [1]
Mucus is produced by goblet cells and submucosal glands under normal conditions and may increase in illness. 'Sputum' or 'phlegm' = airway mucus from trachea/bronchi/bronchioles. Exudates = protein-rich fluid leaked from capillaries into alveoli due to inflammatory response, usually infection. [1]
Practical point: Young children swallow sputum; a parent reporting "wet-sounding cough" does not mean the child is truly productive. Beware of the "sputum sound" — it may be nasal mucus dripping posteriorly, not lower airway secretion.
Specific cough associations: [1]
| Cough type | Association | Explanation |
|---|---|---|
| Whooping cough | Pertussis | Paroxysmal cough followed by inspiratory "whoop" due to forced inspiration through narrowed glottis |
| Barking or brassy cough | Croup, tracheomalacia, habit cough | Inflammation/collapse of extrathoracic airway produces seal-bark quality |
| Paroxysmal (± whoop) | Pertussis, Mycoplasma, parapertussis, virus | |
| Nocturnal | Upper or lower respiratory allergy, sinusitis | Postural increase in postnasal drip, nocturnal bronchoconstriction |
| Tight (wheezy) | Reactive airway/Asthma | Bronchoconstriction causing audible wheeze with cough |
| Staccato | Chlamydia | Short, choppy cough in afebrile neonate — classic for Chlamydia trachomatis pneumonia |
| Honking | Psychogenic/habit | Bizarre, loud, draws attention; disappears in sleep |
| Dry, repetitive, disappears with sleep | Habit cough | Cortical drive ceases during sleep |
Exam Pearl
Only brassy vs non-brassy cough has been validated for sensitivity (0.81) and specificity (0.57) for tracheomalacia. All other cough-character associations are clinically useful but not rigorously validated. [1]
After feeding? In the middle of the night? When the weather changes and turns cold? When someone smokes? With exertion? Associated with fever? Associated with runny nose? [1]
| Timing | Points to… | Why? |
|---|---|---|
| After feeding | GER, aspiration | Swallowing incoordination or reflux triggers cough receptors in esophagus/pharynx |
| Middle of the night | Asthma, sinusitis | Circadian variation in cortisol + vagal tone; postnasal drip worsens supine |
| Cold weather/weather change | Asthma | Cold air triggers airway hyperreactivity |
| Smoke exposure | Reactive airway | Direct chemical irritation + bronchoconstriction |
| With exertion | Asthma, heart failure | Exercise-induced bronchoconstriction; exertional pulmonary congestion |
| With runny nose | Viral URTI | Postnasal drip mechanism |
| Improves at night (disappears with sleep) | Psychogenic/habit cough | Loss of voluntary cortical drive |
The most common stimulus of cough is irritation or inflammation of the respiratory epithelium. [1]
4. Acute Cough in Children
Acute cough: a recent onset of cough lasting less than 3 weeks. [1]
Viral URTIs account for most acute cough at all ages. Self-limiting. Usually lasts 1–3 weeks. [1]
| Level | Viral | Bacterial |
|---|---|---|
| URI | Influenza, RSV, parainfluenza, adenovirus, rhinovirus, human coronavirus, human metapneumovirus, bocavirus | — (usually viral) |
| LRI | Same viruses | Streptococcus pneumoniae, Haemophilus influenzae, Pseudomonas (if immunocompromised), Chlamydia (if neonate) |
Acute cough can also be an exacerbation of a pre-existing condition: asthma, bronchiectasis, upper airway cough syndrome (postnasal drip). [1]
Main issues to sort out: (1) Severity — does this patient need supportive treatment? (2) Etiology — infectious vs non-infectious; if infectious, can you rule out lower respiratory tract infection? (3) Likely organism. [1]
Examination checklist: [1]
- Temperature (fever)
- Vital signs
- Respiratory distress? → Respiratory rate, retractions/insucking/accessory muscle use, cyanosis, SpO₂, dyspnoea/SOB
- Chest exam: deformity, percussion, auscultation (wheeze, crepitations, rhonchi)
- Associated findings: skin rash, eczema, tonsils, lymph nodes, rhinorrhoea
Age-specific tachypnoea thresholds (critical for exams): [1]
| Age | Tachypnoea threshold (breaths/min) |
|---|---|
| < 2 months | > 60 |
| 2–12 months | > 50 |
| > 1 year | > 40 |
High Yield
The absence of fever, tachypnoea, and chest signs is most useful for ruling out lower respiratory involvement. [1] If all three are absent, you can be fairly confident this is an uncomplicated URI.
Most children with cough due to a simple URI do not need any investigations. [1]
A CXR should be considered if: [1]
- Lower respiratory tract signs (±)
- Relentlessly progressive cough (e.g., past the 2-week point)
- Haemoptysis
- An undiagnosed chronic respiratory disorder
Other investigations (depending on DDx): [1]
- CBC with differentials
- Nasopharyngeal aspirate (NPA) for common viruses and Mycoplasma
- Sputum Gram stain and culture (if old enough to expectorate)
- Blood culture — low detection rate even if bacterial aetiology (important exam point: don't rely on blood culture alone)
Approach to try to arrive at a specific diagnosis for acute cough: [1]
| Question | Features | Likely diagnosis |
|---|---|---|
| Is this an acute URI? | Coryzal symptoms, fever, sore throat | URI |
| Is this a croup syndrome? | Stridor, 'barking' or 'croupy cough', hoarseness, ± fever | Viral croup, recurrent spasmodic croup, bacterial tracheitis |
| Is this a lower respiratory tract illness? | Tachypnoea (age-specific thresholds), respiratory distress with ↑WOB, chest signs (crepitations or wheeze/rhonchi), fever | Acute bronchiolitis, pneumonia (viral/bacterial), asthma |
| Is this an allergic/atopic illness? | Seasonal and diurnal variation, association with rhinitis, posture, 'clearing of throat', triggers (dust, pollutant, pollen) | Postnasal drip from allergic rhinitis, reactive airway/asthma |
| Is this an acute exacerbation of a chronic disorder? | Failure to thrive, finger clubbing, chest deformity, features of atopy | → Continue with chronic cough workup |
5. Chronic Cough in Children
ACCP (Chest 2006): Paediatric chronic cough = daily cough lasting > 4 weeks [1]
BTS (Thorax 2007): Chronic cough = cough lasting > 8 weeks. Recognises a 'grey' area of 'subacute cough' between 2–8 weeks. [1]
Why 4 weeks (ACCP)? Because the natural history of URI in children shows cough lasting 1–3 weeks, and one study found 10% of preschool children still coughing 25 days after URI. Choosing 4 weeks avoids over-investigating normal post-viral cough while catching truly persistent pathology. [1]
BTS subdivision: [1]
- Specific cough: Cough with signs/symptoms suggestive of an associated respiratory or systemic problem
- Non-specific cough: Dry cough in the absence of identifiable respiratory disease
Exam Note
For HKUMed exams, use the ACCP definition ( > 4 weeks) as the primary threshold unless specified otherwise. The lecture presents both but focuses on the ACCP guideline.
How did the cough start? What is the quality? When did it start? What triggers it? [1]
| Feature | Examples | Differential diagnosis |
|---|---|---|
| Very acute onset / after choking | Sudden cough in toddler | Inhaled foreign body |
| With URI | Post-viral cough | Post-viral cough |
| Neonatal onset | Born coughing or cough from first weeks | Aspiration, congenital malformation, cystic fibrosis, primary ciliary dyskinesia |
| Productive (moist/wet) | Daily wet cough | Chronic suppurative disease (e.g., bronchiectasis) |
| Paroxysmal ± whoop | Pertussis | |
| Haemoptysis | Adolescent with haemoptysis | TB, bronchiectasis, AV malformation |
| Bizarre honking, increases with attention | Psychogenic cough | |
| Dry, repetitive, disappears with sleep | Habit cough | |
| Exercise, cold air, early morning | Asthma | |
| Feeding | Recurrent aspiration |
Specific cough = associated with signs and symptoms of an underlying respiratory or systemic disease. [1]
| Abnormality | Examples of aetiology |
|---|---|
| Wheeze | Intrathoracic airway lesion (asthma, foreign body) |
| Crepitations | Parenchymal disease |
| Chest pain | Arrhythmia, asthma, increased respiratory distress (parenchymal disease) |
| Chest wall deformity | Chronic airway or parenchymal disease |
| Digital clubbing | Chronic suppurative lung disease |
| Daily moist/productive cough | Suppurative lung disease |
| Failure to thrive | Serious systemic including pulmonary illness |
| Feeding difficulties | Serious systemic including pulmonary illness, aspiration |
| Hypoxia/cyanosis | Airway or parenchymal disease, cardiac disease |
| Neurodevelopmental abnormality | Aspiration lung disease |
| Recurrent pneumonia | Immunodeficiency, congenital lung abnormalities, tracheo-oesophageal H fistula |
The age at which chronic cough begins narrows the differential significantly. [1]
| Infancy | Early childhood | Late childhood / Adolescence |
|---|---|---|
| Aspiration | Aspiration | Aspiration (degenerative neuromuscular disease) |
| Reactive airway | Asthma | Asthma |
| Congenital malformation: laryngotracheomalacia, bronchomalacia, vascular compression (ring/sling, innominate artery) | Bronchiectasis (immunodeficiency, CF, post-infectious) | Bronchiectasis (immunodeficiency, CF, post-infectious) |
| Infection: Chlamydia, pertussis, TB, post-RSV | Infection: viral, TB, Mycoplasma, fungal | Infection: viral, TB, Mycoplasma, fungal |
| Passive smoking, congenital heart disease | Sinusitis | Sinusitis |
| Smoking (active and passive) | ||
| Psychogenic | ||
| Mediastinal tumour |
Usually post-viral cough or another episode of acute infection. Others: foreign body, asthma, GERD etc. [1]
Management approach: [1]
- Evaluate for tobacco smoke and other pollutants — prevalence of chronic cough in children < 11 yrs with 2 smoking parents is 50%
- Assess the child's activity level
- Address parental expectations and concerns
- Watch, wait and review — likely to resolve without specific treatment
- Absence of specific cough pointers = reassurance
Growth and development, respiratory distress, digital clubbing, upper respiratory tract (sinusitis signs, allergic rhinitis signs), lower respiratory tract (chest deformity — Harrison sulcus, pectus carinatum, barrel chest; hyperresonance; crepitations, wheeze, rhonchi), cardiac (murmur/heart failure), skin (eczema). [1]
According to history and PE, developmentally appropriate: [1]
| Investigation | What it screens for |
|---|---|
| CXR | Pneumonia, TB, foreign body, chest deformity, cardiac enlargement |
| Peak flow ± lung function study | Asthma (reversible airway obstruction) |
| CBC with differentials | Eosinophilia (allergy), neutrophilia (bacterial infection), lymphopaenia (immunodeficiency) |
| Mantoux test (MT5) / PPD | TB |
| Interferon-based test (IGRA) | TB (more specific than MT) |
| Sputum or gastric aspirate | AFB for TB |
| HRCT | Bronchiectasis, interstitial lung disease |
| Nasal NO / Cilia study / Sweat test | Primary ciliary dyskinesia (low nasal NO + abnormal cilia), cystic fibrosis (elevated sweat chloride) |
| Immunoglobulin pattern | Primary immunodeficiency |
| pH probe | GERD |
| Video fluoroscopy | Swallowing incoordination / aspiration |
| Bronchoscopy with BAL | Foreign body, chronic infection, suppurative disease |
6. Treatment Principles
Cough is a symptom telling you something is wrong. Find the cause. Treat the underlying cause if indicated. Very diverse treatment: bronchodilator, surgery, antibiotics, anti-TB, anti-fungal, stop smoking etc. [1]
No specific antiviral drug available for most viral infections causing 'bronchitis' or pneumonia. [1]
- Anti-virals for influenza: amantadine, oseltamivir, zanamivir
- Not to treat cough per se — neuraminidase inhibitors only shorten fever by ~1.5 days
- Problem with increasing resistance (esp. amantadine)
| Age group | Most common bacteria | Empiric antibiotic |
|---|---|---|
| < 3 weeks (neonates) | Group B Strep, E. coli, Listeria | Ampicillin + gentamicin |
| 3 weeks – 3 months | S. pneumoniae, Chlamydia trachomatis, B. pertussis | Amoxicillin ± macrolide (if Chlamydia suspected) |
| 4 months – 4 years | S. pneumoniae, H. influenzae | Amoxicillin or Augmentin |
| ≥ 5 years | Mycoplasma, Chlamydia pneumoniae, S. pneumoniae | Macrolide (clarithromycin/azithromycin) |
7. Cough Suppressants in Children — The Ethical and Evidence-Based Case Against Them
This section is extremely high yield as it represents a key take-home message of the lecture and a common exam theme.
Cough is a natural, protective, beneficial mechanism. [1]
No good evidence to demonstrate effectiveness of OTC cold medication in preschool children. [1]
Cochrane 2004 (7 paediatric studies, 516 children): [1]
- Antitussives no more effective than placebo
- No study on expectorants met inclusion criteria
- 1 trial favoured mucolytic (letosteine) over placebo from day 4–10
- 2 studies showed no difference between antihistamine-decongestant combinations and placebo
- 1 trial showed antihistamine was no more effective than placebo
- Conclusion: no good evidence for or against the effectiveness of OTC medicine in acute cough
| Category | Examples |
|---|---|
| Antihistamine | Diphenhydramine, cyproheptadine, brompheniramine, chlorpheniramine |
| Antipyretic/analgesic | Paracetamol, ibuprofen |
| Antitussive | Codeine, dextromethorphan, hydrocodone |
| Expectorant | Guaifenesin |
| Nasal decongestant | Ephedrine, phenylephrine, pseudoephedrine, phenylpropanolamine |
Codeine: narcotic with addictive potential. Dose-related toxicity: respiratory depression and narcosis. Side effects: somnolence, ataxia, miosis, vomiting, rash, swelling, itching. [1]
Dextromethorphan: considered non-addictive but abused by teenagers — ingesting huge doses results in bizarre behaviour. CNS depression. [1]
No FDA-approved dosing exists for children < 2 years of age. Death and morbidity reported over and over again worldwide including HK. [1]
AAP & ACCP Recommendations (Exam-Critical)
AAP (1997): There are no well-controlled studies to support efficacy of codeine- or dextromethorphan-containing antitussives in children. Suppression of cough in many pulmonary diseases may be hazardous and contraindicated. Dosages for children are extrapolated from adult data. Education of parents about lack of proven effects and potential risks is needed. [1]
ACCP (2006): Doctors should refrain from recommending cough suppressants and other OTC cough medications for young children. [1]
2007: Manufacturers voluntarily withdrew OTC cough-cold medicines for children < 2 years from the US market. [1]
A paediatrician is a child's advocate. We treat the child, not the parents. Have to work with caretakers — our role is to educate. Natural course of the illness. Preventive measures when applicable. Symptomatic relief is not everything. Appropriate therapy includes avoiding inappropriate therapy. Patients are not (only) customers. [1]
This is an ethical/professional stance the lecture explicitly states. In an OSCE or SAQ, showing awareness that refusing to prescribe an unnecessary OTC cough medicine is the correct management earns marks.
8. Integration: Key Conditions Causing Cough in Children
- Definition: URTI symptoms followed by LRTI in children < 2 years [3]
- Peak: 1–9 months, most common in winter
- Microbiology: RSV (50–80%), rhinovirus, parainfluenza, adenovirus, HMPV
- Clinical: Preceding coryzal symptoms → SOB, cough, wheezing/crackles, ± resp distress
- Management: Supportive — fluid support, O₂ support (high-flow, CPAP); nebulized 3% hypertonic saline (1st line at QMH); trial of inhaled SABA (continue only if response); antibiotics only for secondary bacterial infection [3]
- Prevention: Palivizumab (anti-RSV monoclonal antibody) for high-risk infants [3]
- Age: 6 months – 3 years (peak 6–36 months) [3]
- Hallmark: Barking cough, hoarseness, inspiratory stridor [1][3]
- Differentiating from epiglottitis: Croup has barking cough + stridor + prodromal coryzal symptoms. Epiglottitis has NO cough, drooling, dysphagia, toxic appearance, high fever [3]
- Management: Nebulized epinephrine (severe), oral/IM dexamethasone, humidified air
- Paroxysmal spasmodic cough ± whoop [1]
- Post-tussive vomiting, apnoea in young infants
- Diagnosis: NPA culture/PCR for Bordetella pertussis
- Treatment: Macrolide (azithromycin, clarithromycin) — primarily to reduce transmission; doesn't change clinical course once paroxysmal stage is established
- May present as chronic dry cough without audible wheeze [5]
- Diurnal variation (worse at night/early morning), exercise-induced, cold-air-induced [5]
- Diagnosis: Clinical history + spirometry with bronchodilator reversibility (FEV₁ ↑ ≥ 12% AND ≥ 200 mL) [5]
- Investigation: Peak flow variability > 10%, trial of ICS
- Very acute onset or after choking episode [1]
- Age: Typically toddlers (1–3 years) — putting everything in mouth
- CXR: May show unilateral hyperinflation (ball-valve obstruction), atelectasis, or may be normal
- Gold standard: Rigid bronchoscopy (diagnostic + therapeutic)
- Clinical pearl: If history of sudden choking followed by persistent cough/wheeze/stridor, foreign body must be excluded even if CXR is normal
Causes of cough in children may be different from adults. Manifestations may be different from adults. A child with a cough may have a self-limiting problem or a serious illness. Importance of history and physical examination. All children with chronic cough should have thorough clinical review to identify possible underlying respiratory and/or systemic illness. Cough treatment should be based on aetiology. No evidence to support medicine for symptomatic relief. Importance of education. [1]
11. Likely Exam Questions
-
A 7-year-old boy with spastic cerebral palsy has chronic cough. Which history is MOST relevant to delineate the aetiology?
- Answer: Choking on feeding (aspiration). This was directly tested in 2024 MCQ Q93. [8]
-
A 2-year-old was playing with peanuts and suddenly developed cough and stridor. CXR is normal. What is the next step?
- Answer: Rigid bronchoscopy — foreign body aspiration must be excluded regardless of CXR findings.
-
According to ACCP, paediatric chronic cough is defined as daily cough lasting:
- Answer: > 4 weeks [1]
-
List 5 causes of chronic cough in an infant.
- Aspiration, reactive airway, congenital malformation (laryngotracheomalacia, vascular ring), infection (Chlamydia, pertussis, TB, post-RSV), passive smoking, congenital heart disease [1]
-
Why should cough suppressants not be prescribed for preschool children? (4 marks)
- No evidence of efficacy (Cochrane 2004, AAP 1997, ACCP 2006) [1]
- Dosages extrapolated from adult data, not validated in children [1]
- Risk of serious adverse effects: respiratory depression (codeine), CNS depression, death reported [1]
- Cough is protective — suppression can worsen secretion retention [1]
-
A 3-year-old presents with daily wet cough for 8 weeks, failure to thrive, and digital clubbing. What are 3 likely diagnoses and 3 key investigations?
- Diagnoses: Bronchiectasis, cystic fibrosis, primary immunodeficiency
- Investigations: HRCT chest, sweat test, serum immunoglobulins [1]
- A neonate presents with staccato cough, tachypnoea, and bilateral diffuse infiltrates on CXR. What is the most likely organism?
High Yield Summary
Acute cough ( < 3 weeks): Mostly viral URTI — supportive care only. Rule out LRI (fever + tachypnoea + chest signs), croup (stridor + barking cough), foreign body (sudden choking onset), and asthma exacerbation.
Chronic cough ( > 4 weeks ACCP / > 8 weeks BTS): Divide into specific cough (with red-flag signs — clubbing, FTT, wet cough, chest deformity, recurrent pneumonia) and non-specific cough (usually post-viral, tobacco exposure). Investigate according to clinical pointers.
Age matters: Neonatal = congenital/Chlamydia/CF/PCD. Toddler = foreign body/bronchiolitis. Older child = asthma/Mycoplasma/psychogenic/TB/mediastinal tumour.
Cough character matters: Barking = croup/tracheomalacia. Whooping = pertussis. Staccato = Chlamydia. Honking/disappears in sleep = psychogenic/habit. Moist/productive daily = suppurative disease.
Do NOT prescribe OTC cough medicines for young children. No evidence of benefit, significant risk of harm (respiratory depression, death). Treat the underlying cause.
Cough is protective. Suppressing it can be harmful. Educate families. The paediatrician is the child's advocate.
Active Recall - A Child with Cough
[1] Lecture slides: GC 141. A child with cough acute and chronic cough in children.pdf (all pages) [2] Lecture slides: Block C - A child with cough_ acute and chronic cough in children.pdf (p1) [3] Senior notes: MBBS Final MB (Pediatrics) (Felix PY Lai).pdf (p135, p137, p148, p153, p159) [4] Senior notes: Adrian Lui Pediatrics Notes.pdf (p156, p163) [5] Senior notes: Maksim Medicine Notes.pdf (p297) [6] Senior notes: Ryan Ho Respiratory.pdf (p18, p49, p50) [7] Senior notes: MBBS Final MB (Medicine) (Felix PY Lai).pdf (p109–p111) [8] Past papers: 2024 Fourth Summative MCQ.pdf (Q92, Q93)
A Child With Cancer_paediatric Cancers
Paediatric cancers are a diverse group of malignancies arising in children and adolescents, most commonly leukaemias, brain tumours, and lymphomas, often originating from embryonal or developing tissues rather than from environmental exposures.
A Child With Loose Stool
A pediatric presentation of diarrhea, defined as the passage of unusually loose or watery stools with increased frequency, resulting from infectious, dietary, malabsorptive, or functional causes requiring assessment of hydration status and etiology.