What is the recommended treatment for Staphylococcus (Staph) skin infections in pediatric patients?

Treatment of Staphylococcal Skin Infections in Pediatric Patients

For uncomplicated staphylococcal skin infections in children, first-line treatment is cephalexin 25 mg/kg/day divided into 4 doses (or alternatively 2-3 divided doses for improved compliance) for methicillin-susceptible S. aureus (MSSA), with clindamycin or vancomycin reserved for confirmed or suspected MRSA based on local resistance patterns and clinical severity. 1

Initial Antibiotic Selection Based on Infection Severity

Mild, Uncomplicated Infections (Impetigo, Small Abscesses, Folliculitis)

For MSSA infections:

• Cephalexin 25 mg/kg/day divided into 4 doses is the oral agent of choice 1
• Alternative dosing for improved compliance: 22-45 mg/kg/day divided twice daily or 15-25 mg/kg/day divided three times daily 2
• Dicloxacillin 25 mg/kg/day in 4 divided doses is equally effective 1
• Duration: 7 days is typically sufficient 1

For suspected community-acquired MRSA (CA-MRSA):

• Clindamycin 10-20 mg/kg/day in 3 divided doses orally is preferred ONLY if local clindamycin resistance rates are <10% 1, 3
• TMP-SMX 8-12 mg/kg/day (based on trimethoprim component) in 2 divided doses is an alternative 1
• Critical caveat: A 2011 randomized controlled trial showed no significant difference between cephalexin and clindamycin for uncomplicated pediatric skin infections when appropriate drainage was performed (94% vs 97% improvement at 48-72 hours, P=0.50), even though 69% of infections were MRSA 4

Moderate to Severe Infections Requiring Hospitalization

For MSSA infections:

• Nafcillin 50 mg/kg/dose IV every 4-6 hours 1
• Cefazolin 33 mg/kg/dose IV every 8 hours (can be used if penicillin allergy is not type 1 hypersensitivity) 1, 3

For confirmed or suspected MRSA:

• Vancomycin 40 mg/kg/day in 4 divided doses IV (or 15 mg/kg/dose every 6 hours) is the parenteral drug of choice 1, 3
• Indications for vancomycin include: critically ill patients, failure to improve on beta-lactam therapy after 24-48 hours, high local MRSA prevalence, or confirmed MRSA on culture 3
• Linezolid 10 mg/kg every 8 hours IV or PO (for children <12 years) is an alternative MRSA-active agent 1, 3, 5
• Clindamycin 25-40 mg/kg/day in 3 divided doses IV (or 10-13 mg/kg/dose every 6-8 hours) can be used if local resistance is low 1, 3

Special Considerations for Staphylococcal Scalded Skin Syndrome (SSSS)

• Initial empiric therapy should be an anti-staphylococcal beta-lactam (cefazolin or nafcillin) 3
• Add clindamycin 10-13 mg/kg/dose IV every 6-8 hours as adjunctive therapy to suppress exotoxin production at the ribosomal level 3
• Switch to vancomycin if the patient is critically ill, not improving on beta-lactam therapy, or in communities with high MRSA prevalence 3
• Treatment duration: 7-14 days guided by clinical response 3

Critical Clinical Pitfalls and Caveats

Age-related restrictions:

• Tetracyclines (doxycycline, minocycline) should NOT be used in children <8 years of age 1, 3
• Linezolid dosing varies by age: neonates <7 days (especially preterm <34 weeks gestational age) should receive 10 mg/kg every 12 hours, then advance to every 8 hours by day 7 of life 5

Resistance considerations:

• Clindamycin has potential for cross-resistance with erythromycin-resistant strains and inducible resistance in MRSA 1
• Before using clindamycin empirically, verify local clindamycin resistance rates are <10% 3
• Erythromycin is no longer recommended due to widespread resistance 1

The importance of drainage:

• Spontaneous drainage or surgical drainage is critical for success—in one study, 97% of patients had drainage performed, and antibiotic choice became less important 4
• Fastidious wound care and close follow-up (48-72 hours) are likely more important than initial antibiotic selection for uncomplicated abscesses 4

Predictors of treatment failure:

• Fever at presentation and age <1 year are associated with early treatment failures, regardless of antibiotic used 4
• Initial erythema >5 cm was NOT associated with treatment failure in one study 4

Topical Therapy for Localized Infections

• Mupirocin 2% topical ointment is recommended for localized minor staphylococcal skin infections 3

Recurrent Infections and Decolonization

• After obtaining cultures of recurrent abscesses, treat with a 5-10 day course of an antibiotic active against the pathogen 1
• Consider a 5-day decolonization regimen: intranasal mupirocin twice daily, daily chlorhexidine washes, and daily decontamination of personal items (towels, sheets, clothes) for recurrent S. aureus infections 1