Clinical Features of Typical and Atypical Pediatric Pneumonia
Typical and atypical pneumonia in pediatric patients have distinct clinical features that guide diagnosis and treatment, with bacterial pneumonia typically presenting with high fever, focal findings, and lobar consolidation, while atypical pneumonia commonly presents with gradual onset, prominent cough, and diffuse interstitial patterns.
Clinical Features
Typical (Bacterial) Pneumonia
Typical pneumonia is most commonly caused by Streptococcus pneumoniae, Haemophilus influenzae, and Staphylococcus aureus.
Key clinical features include:
- Acute onset with high fever (often >39°C)
- Productive cough with purulent sputum
- Tachypnea and respiratory distress
- Focal findings on examination (crackles, decreased breath sounds)
- Chest pain (pleuritic)
- Lobar consolidation on chest radiograph
- Elevated white blood cell count with neutrophil predominance
Atypical Pneumonia
Atypical pneumonia is commonly caused by Mycoplasma pneumoniae, Chlamydophila pneumoniae, and in younger infants, Chlamydia trachomatis.
Key clinical features include:
- Gradual onset of symptoms
- Prominent dry, non-productive cough
- Low-grade fever
- Diffuse interstitial or patchy infiltrates on chest radiograph
- Extrapulmonary manifestations (headache, malaise, myalgia)
- Normal or slightly elevated white blood cell count
Age-Specific Considerations
- Infants (<1 year): May present with nonspecific symptoms like irritability, poor feeding, and apnea rather than classic respiratory symptoms
- Preschool children (1-5 years): Typical pneumonia more common, with high fever and respiratory distress
- School-age children (>5 years): Higher incidence of atypical pneumonia, especially Mycoplasma
Treatment Recommendations
Typical (Bacterial) Pneumonia
Outpatient treatment (<5 years old):
- First-line: Amoxicillin oral (90 mg/kg/day in 2 doses) 1, 2
- Alternative: Amoxicillin-clavulanate (amoxicillin component 90 mg/kg/day in 2 doses) 1
Outpatient treatment (≥5 years old):
- First-line: Amoxicillin oral (90 mg/kg/day in 2 doses, maximum 4 g/day) 1
- For children with no clear distinction between bacterial and atypical pneumonia, a macrolide can be added 1
Inpatient treatment (fully immunized):
- Ampicillin or penicillin G 1, 2
- Alternatives: Ceftriaxone or cefotaxime 1
- Add vancomycin or clindamycin if MRSA suspected 1, 2
Inpatient treatment (not fully immunized or high local resistance):
Atypical Pneumonia
Outpatient treatment (all ages):
- First-line: Azithromycin (10 mg/kg on day 1, followed by 5 mg/kg/day once daily on days 2-5) 1, 3
- Alternatives: Clarithromycin (15 mg/kg/day in 2 doses) or erythromycin 1
- For children >7 years: Doxycycline is an option 1
Inpatient treatment:
- Azithromycin (in addition to β-lactam if diagnosis uncertain) 1
- Alternatives: Clarithromycin, erythromycin, doxycycline (>7 years), or levofloxacin (for children who have reached growth maturity) 1
Monitoring and Follow-up
Children on appropriate therapy should show clinical improvement within 48-72 hours 1. If no improvement or deterioration occurs, further investigation is warranted, including:
- Reassessment of diagnosis
- Evaluation for complications (effusion, empyema)
- Consideration of resistant organisms or viral co-infection
Important Clinical Pearls
Diagnostic challenges: Clinical features alone cannot reliably distinguish between typical and atypical pneumonia; radiographic findings and laboratory tests help guide diagnosis.
Treatment duration: Standard treatment duration is 5-7 days for most uncomplicated pneumonia cases 2, 4.
Antimicrobial resistance: Consider local resistance patterns when selecting empiric therapy 2.
Common pitfall: Treating all pediatric pneumonia with macrolides alone. Evidence shows that empirical macrolide treatment is not necessary for all children with non-severe CAP 5.
Risk assessment: Children with normal vital signs and no signs of severe illness have a low risk (<5%) of pneumonia and may not require antibiotics or radiographs 6.