Introduction
Lower respiratory infections in children are of three kinds: bronchiolitis (small airways, infants), pneumonia (lung tissue, any age) and pleuritis with effusion or empyema, usually a complication of pneumonia.
Bronchiolitis
A viral infection of the bronchioles in children under 2 years, most often 2–6 months old, in winter. RSV causes most cases; also rhinovirus, metapneumovirus, parainfluenza. Infected cells slough, the small airways fill with mucus and debris, and air is trapped.
Clinical picture
- 1–3 days of runny nose and cough, then fast breathing, recession, poor feeding.
- On listening: fine crackles and/or wheeze all over the chest. Young infants may present with apnoea.
- Worst on days 3–5; cough may last 3–4 weeks.
- Higher risk: under 3 months, preterm birth, chronic lung disease, congenital heart disease, neuromuscular disease, immune deficiency.
Management
The diagnosis is clinical and the treatment is supportive:
- Oxygen if SpO₂ stays below 90–92%; high-flow nasal cannula or CPAP if tiring.
- Feeding support: small frequent feeds, nasogastric or IV fluids if intake is under 50–75% of normal.
- Gentle nasal suction if a blocked nose limits feeding.
Not helpful: salbutamol, adrenaline, steroids, antibiotics, chest physiotherapy, hypertonic saline routinely.
Prevention: the long-acting antibody nirsevimab, one injection before the first RSV season; palivizumab (monthly) for high-risk infants; a maternal RSV vaccine in late pregnancy; hand hygiene and no smoking.