What are the common antibiotics used to treat infectious diseases in pediatrics?

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Antibiotic Treatment of Infectious Diseases in Pediatrics

The first-line antibiotic treatment for pediatric infectious diseases should be selected based on the specific infection site, patient age, and likely pathogens, with narrow-spectrum antibiotics preferred whenever possible to prevent antimicrobial resistance. 1

Common Antibiotics by Infection Site

Respiratory Tract Infections

Upper Respiratory Tract (Ear, Nose, Throat)

  • First-line: Amoxicillin 90 mg/kg/day divided in 2 doses 1, 2
  • Alternatives:
    • Amoxicillin-clavulanate (for beta-lactamase producing organisms)
    • Macrolides (for atypical pathogens or penicillin allergy)

Lower Respiratory Tract (Pneumonia)

  • Outpatient treatment:

    • Children <5 years: Amoxicillin 90 mg/kg/day in 2 doses
    • Children ≥5 years: Amoxicillin 90 mg/kg/day in 2 doses (max 4g/day)
    • Consider macrolides for atypical pneumonia
  • Inpatient treatment:

    • Ampicillin 150-200 mg/kg/day divided every 6 hours
    • Alternatives: Cefotaxime (150 mg/kg/day every 8 hours) or Ceftriaxone (50-100 mg/kg/day every 12-24 hours) 1

Neonatal Infections

Neonatal Sepsis and Pneumonia

  • First-line: Ampicillin plus Gentamicin 1
    • Ampicillin dosing by age and weight:
      Postnatal Age Weight Recommended Dose
      ≤7 days ≤2000 g 50 mg/kg/day every 12 hours
      ≤7 days >2000 g 75 mg/kg/day every 8 hours
      >7 days <1200 g 50 mg/kg/day every 12 hours
      >7 days 1200-2000 g 75 mg/kg/day every 8 hours
      >7 days >2000 g 100 mg/kg/day every 6 hours

Skin and Soft Tissue Infections

  • Mild-moderate: Cephalexin or Clindamycin (if MRSA suspected)
  • Severe: Vancomycin or Clindamycin plus a beta-lactam 1

Genitourinary Tract Infections

  • First-line: Amoxicillin for susceptible organisms 2
  • Alternatives:
    • Trimethoprim-sulfamethoxazole
    • Cephalosporins (cefixime, ceftriaxone)
    • Nitrofurantoin for lower UTIs

Bone and Joint Infections

  • First-line: Cefotaxime plus anti-staphylococcal coverage 3
  • Alternatives: Based on culture results and local resistance patterns

Age-Specific Considerations

Neonates (0-28 days)

  • Special considerations:
    • Lower doses and extended intervals due to immature renal function 1, 4
    • Avoid chloramphenicol, sulfonamides, and tetracyclines due to toxicity 4
    • Ampicillin + gentamicin is standard empiric therapy for suspected sepsis

Infants and Young Children

  • Common pathogens:
    • Respiratory: S. pneumoniae, H. influenzae, S. pyogenes
    • UTI: E. coli, other Enterobacteriaceae
    • Skin: S. aureus, S. pyogenes

Older Children and Adolescents

  • Dosing: Approaches adult dosing based on weight
  • Considerations: Increased compliance issues, different pathogen distribution

Antibiotic Stewardship Principles

  • Narrow-spectrum first: Use the narrowest spectrum antibiotic effective against the suspected pathogen 1
  • Appropriate duration: Avoid unnecessarily prolonged courses
  • Culture when possible: Guide therapy based on susceptibility results
  • Monitor for improvement: Assess clinical response within 48-72 hours 1

Special Situations

Antimicrobial Resistance Concerns

  • MRSA: Consider local prevalence when selecting empiric therapy
  • Drug-resistant S. pneumoniae: May require higher amoxicillin doses (90 mg/kg/day)
  • Beta-lactamase producers: Use beta-lactamase inhibitor combinations

H. pylori Infection (Adolescents)

  • Triple therapy: Amoxicillin 1g twice daily + clarithromycin 500mg twice daily + lansoprazole 30mg twice daily for 14 days
  • Dual therapy: Amoxicillin 1g three times daily + lansoprazole 30mg three times daily for 14 days 2

Monitoring and Safety

  • Renal function: Adjust doses for aminoglycosides and certain beta-lactams in renal impairment
  • Drug levels: Monitor aminoglycoside levels to prevent toxicity
  • Adverse effects: Watch for diarrhea (including C. difficile), rash, and allergic reactions 1, 2

Pitfalls to Avoid

  • Overuse of broad-spectrum antibiotics: Increases resistance and adverse effects
  • Inadequate dosing: Particularly in rapidly growing children
  • Failure to adjust therapy: When culture results become available
  • Overlooking supportive care: Ensure adequate hydration, oxygenation, and nutrition alongside antibiotic therapy 1

Remember that local resistance patterns may necessitate adjustments to these recommendations, and clinical judgment should guide therapy decisions in individual cases.

References

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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