Related Subjects:
|Pneumonia in Children
|Cystic Fibrosis
|Sweat Test
|Encopresis in Children
|Enuresis/Bedwetting in Children
|Acute Glomerulonephritis in Children
|Nephrotic Syndrome in Children
|Acute Appendicitis in Children
|Gastro-oesophageal reflux in Children
|Intussusception in Children
|Panayiotopoulos Syndrome in Children
|Reflex anoxic attacks in Children
|Paediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal Infections
Viral and Bacterial LRTI in Children
🧒 Lower Respiratory Tract Infections (LRTIs) are a major cause of childhood morbidity worldwide.
👉 Viral infections predominate in < 2 years (e.g., bronchiolitis), while bacterial causes become more relevant in older children.
⚠️ Always ensure follow-up if symptoms persist after discharge, as complications (empyema, post-infectious wheeze, bronchiectasis) may develop.
🦠 Causes
- Bacterial Causes:
- 🟠 Pneumococcus: Major cause of bacterial pneumonia; lobar consolidation, pleural effusion possible.
- 🟡 Mycoplasma pneumoniae: “Atypical” pneumonia in school-aged children with slow onset, dry cough, headache.
- 🟢 Haemophilus influenzae (esp. non-typable): Important in unvaccinated children; can cause severe pneumonia.
- 🔴 Staphylococcus aureus: Aggressive, necrotising pneumonia; classically post-influenza, with pneumatocoeles or empyema.
- ⚫ Tuberculosis: Chronic cough, weight loss, night sweats in endemic areas or high-risk groups.
- Viral Causes:
- 🟢 Respiratory Syncytial Virus (RSV): Leading viral LRTI cause under 2 years → bronchiolitis with wheeze & apnoea risk.
- 🟠 Influenza A & B: Sudden high fever, myalgia, coryza → secondary bacterial pneumonia risk.
- 🟡 Parainfluenza: Classically linked with croup but can cause bronchiolitis/pneumonia.
- 🔵 Adenovirus: Severe LRTI; risk of chronic lung damage (bronchiectasis, obliterative bronchiolitis).
- 🟣 Human Metapneumovirus: RSV-like illness; peak in winter/spring.
- ⚪ Seasonal Coronaviruses: Usually mild, but can mimic RSV in infants.
📋 Signs and Symptoms
- General: 🌡️ Fever, malaise, poor feeding, irritability in infants.
- Respiratory Distress:
- 📈 Tachypnoea (age-specific cut-offs per WHO/NICE).
- 💙 Cyanosis (late sign of hypoxaemia).
- 🔊 Grunting (attempt to increase PEEP).
- ⬇️ Intercostal recession, nasal flaring, head bobbing.
- 💪 Use of accessory muscles.
- Older children: Lobar signs – pleuritic chest pain, bronchial breathing, dullness to percussion, crackles.
📊 Monitoring
- 🌡️ Temperature (T): trends for fever.
- ❤️ Pulse rate (P): tachycardia may suggest fever, dehydration, or sepsis.
- 🫁 Respiratory rate (R): key for severity scoring.
- 📉 SpO₂: hypoxaemia < 92% = admit.
🏥 Admission Criteria
- SpO₂ < 92% persistently.
- Severe respiratory distress (grunting, head bobbing, cyanosis).
- Apnoeas or inability to feed.
- Concerns re: social support, poor follow-up, or significant comorbidities (CHD, immunosuppression).
🧪 Investigations
- Not routinely needed in mild CAP managed at home.
- Consider in hospitalised/severe cases:
- 📸 Chest X-ray – if hypoxic, severe, or poor response.
- 🩸 FBC & CRP – may help bacterial vs viral but not definitive.
- 💉 Blood cultures / sputum (if possible).
- 🧪 Viral PCR (RSV, influenza) in admitted infants – guides cohorting/isolation.
💊 Management
- Viral LRTI (esp. < 2 years):
- Supportive care: fluids, oxygen, NG feeding if poor intake.
- No role for antibiotics unless bacterial superinfection suspected.
- RSV prophylaxis (Palivizumab) in high-risk infants (e.g., preterm, congenital heart disease).
- Bacterial CAP:
- First-line (UK, per NICE): Amoxicillin oral.
- Severe/hospitalised: IV co-amoxiclav or cefuroxime.
- Atypical suspicion (school age, extrapulmonary features): add macrolide (azithromycin, clarithromycin).
- Staph suspicion (rapidly worsening, pneumatocoele): flucloxacillin IV.
⚠️ Complications
- Empyema, lung abscess.
- Sepsis, septic shock.
- Post-infectious wheeze, bronchiolitis obliterans (adenovirus).
- Recurrent pneumonia → consider immunodeficiency, cystic fibrosis.
✅ Key Learning Points
- Most preschool LRTIs are viral – avoid overuse of antibiotics.
- Always assess severity (feeding, SpO₂, recession, apnoea).
- Admit if hypoxic, distressed, or unable to feed.
- Use antibiotics judiciously – amoxicillin for bacterial CAP, macrolides for atypical pathogens.
- Arrange follow-up if symptoms persist beyond expected course.