Treatment of Impetigo in an 8-Year-Old Child
For localized impetigo in an 8-year-old child, start with topical mupirocin 2% ointment applied three times daily for 5 days, which is equally or more effective than oral antibiotics and causes fewer side effects. 1, 2
First-Line Topical Therapy for Limited Disease
Topical mupirocin is the preferred initial treatment for nonbullous impetigo affecting small areas (up to 100 cm² or approximately 10 lesions), as it demonstrates superior efficacy compared to placebo (OR 6.49) and equal or better outcomes than oral erythromycin 1, 3, 4
Topical retapamulin is an FDA-approved alternative, applied twice daily for 5 days, with clinical success rates of 85-90% in pediatric patients 2
Topical fusidic acid shows equivalent efficacy to mupirocin (OR 1.76, not statistically different) and can be used where available 3, 4
When to Use Oral Antibiotics
Switch to oral antibiotics if the child has:
- Extensive disease (>10 lesions or >100 cm² affected area) 5
- Bullous impetigo with large, flaccid bullae 5
- Systemic symptoms or signs of deeper infection 1
- Inability to apply topical therapy practically 5
Oral Antibiotic Selection
First choice: Cephalexin 25-50 mg/kg/day divided into 3-4 doses for 7 days (covers both S. aureus and Streptococcus pyogenes) 6
Alternative: Dicloxacillin 25-50 mg/kg/day divided into 4 doses for methicillin-susceptible S. aureus 6
For penicillin allergy: Clindamycin 20-30 mg/kg/day divided into 3 doses (only if local MSSA resistance <10%) 6, 7
Avoid penicillin V as it is seldom effective for impetigo 8, 4
Avoid erythromycin due to rising resistance rates and inferior efficacy compared to other options 5, 8
MRSA Considerations
In communities with high MRSA prevalence (>10% local resistance), consider clindamycin 30-40 mg/kg/day divided into 3 doses if local clindamycin resistance is <10% 6, 7
TMP-SMX 8-12 mg/kg/day (based on trimethoprim) divided into 2 doses covers MRSA but should not be used as monotherapy due to inadequate streptococcal coverage 1, 5
Linezolid 10 mg/kg every 12 hours is reserved for confirmed MRSA when other options fail 6
Critical Pitfalls to Avoid
Do not use doxycycline or other tetracyclines in this 8-year-old child, as they should be avoided in children <8 years and used cautiously even at age 8 6, 7
Do not use topical disinfectants as they are inferior to antibiotics and not recommended 5, 3
Do not use TMP-SMX alone for initial empiric therapy due to intrinsic streptococcal resistance 1
Ensure the child returns to school/activities only after 24 hours of appropriate antibiotic therapy to prevent transmission 1