Causes

Bacterial:

• Most common - Strep pneumonia
• Group A strep
• Group B strep (pre-vaccinated infants)
• Staphylococcys aerus (causes pneumatocele appearance on CXR)
• Haemophilus influenza (affects pre-vaccinated or unvaccinated children)
• Atypical pneumonia - Mycoplasma pneumonia (has extrapulmonary manifestations - erythema multiforme)

Viral:

• Most common - RSV
• Parainfluenza
• Influenza

PC

• Cough (typically wet and productive)
• High fever (> 38.5C)
• Increased work of breathing