1817. Comparative In Vitro Activity of Ceftaroline Against Gram-Negative and Gram-Positive Clinically Significant Bacterial Isolates from Patients in a Teaching Hospital.
Session: Poster Abstract Session: Antibacterial Susceptibility Surveillance
Saturday, October 29, 2016
Room: Poster Hall
Background: Ceftaroline is a novel oxyimino cephalosporin with broad-spectrum bactericidal activities against Gram-positive and Gram-negative bacteria. It was approved by the US Food and Drug Administration (FDA) in 2010 for the treatment of acute bacterial skin and soft tissue infections, community-acquired pneumonia and commonly encountered facultative Gram-negative bacterial infections.

Methods: In vitro activities of ceftaroline and comparative drugs were determined against clinically significant isolates obtained from patients with proven bacterial infections. Susceptibility testing was performed using E-test and semi-automated VITEK-2 methods. Data were analyzed according to the interpretative criteria recommended by the Clinical and Laboratory Standards Institute (CLSI).

Results: A total of 556 isolates were tested. Compared with other cephalosporins such as cefepime, cefotaxime, ceftazidime and ceftriaxone, ceftaroline demonstrated excellent activities (MIC90, ≤0.5µg/ml) against Escherichia coli (93.8% were susceptible), Klebsiella pneumoniae (92% were susceptible), Proteus mirabilis (91.7% susceptible), Salmonella spp. (100% susceptible) and Haemophilus influenzae (100% susceptible). It had poor potency (MIC90, >32µg/ml) against Acinetobacter baumannii and Pseudomonas aeruginosa. When matched with the comparative cephalosporins, ceftaroline demonstrated the greatest activity against methicillin-susceptible Staphylococcus aureus (MSSA), with a MIC90 of 0.5µg/ml. In comparison with other agents against coagulase-negative staphylococci (CNS), it showed 2- to 4-fold better potency (MIC90, 1µg/ml) than those of the comparative agents. Ceftaroline also demonstrated excellent activities against both community-associated methicillin-resistant S. aureus (MRSA) and hospital-acquired MRSA with MIC90s of 0.5 and 1µg/ml, respectively. All isolates of Streptococcus agalactiae, S. pneumoniae and Viridans streptococci were highly susceptible to ceftaroline (MIC90s, 0.06, 0.06 and 0.035µg/ml, respectively).

Conclusion: Ceftaroline demonstrated excellent in vitro activity against the majority of clinically significant isolates, except the non-fermenters, obtained from proven cases of bacterial infections,

Vincent Rotimi, MD, PhD, FRCPath, FIDSA1, Wafaa Jamal, MD, PhD, FRCPath1, Hayfaa Abdulkareem, BSc, MSc2, Amal Naji, BSc2 and Fatma Al-Failakawy, BSc2, (1)Microbiology, Faculty of Medicine, Kuwait University, Jabriya, Kuwait, (2)Clinical Microbiology, Mubarak Al Kabeer Hospital, Jabriya, Kuwait


V. Rotimi, AstraZeneca: Investigator , Research support

W. Jamal, None

H. Abdulkareem, None

A. Naji, None

F. Al-Failakawy, None

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