We report a case of persistent bacteremia secondary to methicillin-resistant S. aureus (MRSA) in a preterm neonate successfully treated with daptomycin. Although the MRSA isolate was susceptible to vancomycin, there was no clinical or microbiologic response. Within 3 days of therapy with daptomycin, clinical improvement was noted, along with sterilization of blood cultures. Little data exist on neonatal pharmacokinetics of daptomycin. This report highlights the potential advantage that daptomycin offers in treating severe MRSA infections in neonates.

Linezolid is an antibiotic used to treat highly resistant infections, including vancomycin-resistant enterococci and methicillin-resistant Staphylococcus aureus. Enterococcus faecalis bacteremia occurs in pediatric patients. We present a teenager admitted for bacteremia caused by E faecalis with a distinctive pattern of resistance to linezolid. This organism has the highest MIC to linezolid reported in the literature to date.