Pharmacodynamic comparison of different antimicrobial regimens against Staphylococcus aureus bloodstream infections with elevated vancomycin minimum inhibitory concentration

• Published in: BMC infectious diseases Vol. 20; no. 1; pp. 74 - 9
• Main Authors: da Costa, Thaina Miranda, Cuba, Gabriel Trova, Morgado, Priscylla Guimarães Migueres, Nicolau, David P, Nouér, Simone Aranha, Dos Santos, Kátia Regina Netto, Kiffer, Carlos Roberto Veiga
• Format: Journal Article
• Language: English
• Published: England BioMed Central Ltd 23.01.2020; BioMed Central; BMC
• Subjects: Anti-Bacterial Agents - pharmacokinetics; Anti-Bacterial Agents - pharmacology; Antibacterial agents; Antibiotics; Antiinfectives and antibacterials; Antimicrobial agents; Bacteremia - drug therapy; Bacteremia - microbiology; Bloodstream infections; Brazil; Ceftaroline; Cephalosporins - pharmacokinetics; Cephalosporins - pharmacology; Comparative analysis; Computer simulation; Daptomycin; Daptomycin - pharmacokinetics; Daptomycin - pharmacology; Drug dosages; Drug therapy; Exposure; Glycopeptides; Humans; Infection; Infections; Infectious diseases; Linezolid; Methicillin; Methicillin-Resistant Staphylococcus aureus - drug effects; Microbial Sensitivity Tests; Minimum inhibitory concentration; Monte Carlo Method; Monte Carlo methods; Monte Carlo simulation; Mortality; Neutropenia; Oxacillin; Patient outcomes; Patients; Pharmacodynamic targets; Pharmacodynamics; Pharmacology; Pneumonia; Public health; Public health movements; Retrospective Studies; Sensitivity analysis; Setting (Literature); Staphylococcal infections; Staphylococcal Infections - drug therapy; Staphylococcal Infections - microbiology; Staphylococcus aureus; Staphylococcus aureus - drug effects; Staphylococcus aureus infections; Staphylococcus infections; Stochasticity; Studies; Teaching hospitals; Teicoplanin; Time; Vancomycin; Vancomycin - pharmacokinetics; Vancomycin - pharmacology; Brazil; United States > US; Bloodstream infections; Vancomycin; Ceftaroline; Pharmacodynamic targets; Staphylococcus aureus; Daptomycin
• ISSN: 1471-2334; 1471-2334
• DOI: 10.1186/s12879-020-4782-9

Staphylococcus aureus is one of the major causes of bloodstream infections (BSI) worldwide, representing a major challenge for public health due to its resistance profile. Higher vancomycin minimum inhibitory concentrations (MIC) in S. aureus are associated with treatment failure and defining optimal empiric options for BSIs in settings where these isolates are prevalent is rather challenging. In silico pharmacodynamic models based on stochastic simulations (Monte Carlo) are important tools to estimate best antimicrobial regimens in different scenarios. We aimed to compare the pharmacodynamic profiles of different antimicrobials regimens for the treatment of S. aureus BSI in an environment with high vancomycin MIC. Steady-state drug area under the curve ratio to MIC (AUC/MIC) or the percent time above MIC (fT > MIC) were modeled using a 5000-patient Monte Carlo simulation to achieve pharmacodynamic exposures against 110 consecutive S. aureus isolates associated with BSI. Cumulative fractions of response (CFRs) against all S. aureus isolates were 98% for ceftaroline; 79% and 92% for daptomycin 6 mg/kg q24h and for the high dose of 10 mg/kg q24h, respectively; 77% for linezolid 600 mg q12h when MIC was read according to CLSI M100-S26 instructions, and 64% when MIC was considered at the total growth inhibition; 65% and 86% for teicoplanin, three loading doses of 400 mg q12 h followed by 400 mg q24 h and for teicoplanin 400 mg q12 h, respectively; 61% and 76% for vancomycin 1000 mg q12 h and q8 h, respectively. Based on this model, ceftaroline and high-dose daptomycin regimens delivered best pharmacodynamic exposures against S. aureus BSIs. Teicoplanin higher dose regimen achieved the best CFR (86%) among glycopeptides, although optimal threshold was not achieved, and vancomycin performance was critically affected by the S. aureus vancomycin MIC ≥2 mg/L. Linezolid effectiveness (CFR of 73%) is also affected by high prevalence of isolates with linezolid MIC ≥2 mg/L. These data show the need to continually evaluate the pharmacodynamic profiles of antimicrobials for empiric treatment of these infections.