Pharmacy and Pharmaceutical Sciences Commons^™

Daptomycin Non-Susceptible Mrsa Bacteremia: A Case Report, Jaclyn Cusumano, Pharmd, Anna Marie Morlino, Pharmd, Andrew Moyer, Pharmd

College of Pharmacy Posters

Background

Staphylococcus aureus^{1, 2, 3}

• One of the most common pathogens causing community-acquired and nosocomial infections
• Has rapidly developed resistance to many antibiotics:

Daptomycin ²

• Bactericidal cyclic lipopeptide antibiotic
• Possesses negative charge which attracts calcium to form cationic complex
• Interacts with negatively charged phospholipid heads on bacterial cell membranes, leading to membrane depolarization and cell death

Daptomycin non-susceptible (DNS) S. aureus ^{2, 4, 5}

• Extremely rare - About 60 clinical cases reported
• Defined by an MIC greater than 1 mcg/mL
• Potential mechanisms include:

– Changes in cell membrane and cell wall structure alter daptomycin’s permeability²

• Overexpression and dysregulation …