Approximately 3,000 of clinically significant isolates of different species from respective respective sources in geographically distinct Russian cities will be collected and tested on ceftaroline and other antimicrobials.

Inclusion Criteria:

• Isolates derived from patients' clinical material will be included in the study
• Isolates collected retro- and prospectively will be included in the study (from 01.01.2008 till 31.12.2012)
• Isolates, allocated of a clinical material of adult patients (> 18 years), should make not less than 70 % from total number of included isolates)
• All included isolates should be unique: only one isolate can be included in the study of each biological type from each patient
• All isolates should correspond to clinic-laboratory criteria of the etiologic importance, i.e. should be derived from patients with infection symptoms from the corresponding clinical material
• Case report form (CRF) (Appendix 1) should be correctly completed for each isolate

Exclusion Criteria:

• ESBL-producing representatives of Enterobacteriaceae (ESBL-Extended-spectrum beta-lactamase)
• Isolates, arrived in the central laboratory contaminated or unviable

clinical material form patients in geographically distinct Russian cities