Antimicrobial susceptibility of Gram-negative organisms from intraabdominal infections and evolution of isolates with extended spectrum β-lactamases in the SMART study in Spain (2002-2010).

Introduction: The SMART (Study for Monitoring Antimicrobial Resistance Trends) surveillance study records the antimicrobial susceptibility of Gram-negative bacilli obtain from intraabdominal infections with special focus in isolates with extended spectrum β-lactamases (ESBLs).

Material And Methods: The antimicrobial susceptibility of 8,869 isolates was analyzed by microdilution during the SMART study performed in Spain from 2002 to 2010. Isolates were recovered in 16 centres.

Prevalence and characterization of extended-spectrum beta-lactamases-producing Salmonella enterica isolates in Saragossa, Spain (2001-2008).

We analyzed the prevalence of resistance to extended-spectrum cephalosporins (ESCs) among clinical strains of Salmonella enterica collected by the Laboratory of Clinical Microbiology in the University Clinical Hospital Lozano Blesa in the region of Aragón (Spain), for which very few epidemiological information exists. A total of 2,092 strains of S. enterica were identified in stool samples from patients with gastroenteritis.

In vitro activity of cefditoren and other antimicrobial agents against 288 Streptococcus pneumoniae and 220 Haemophilus influenzae clinical strains isolated in Zaragoza, Spain.

In vitro cefditoren antimicrobial activity was tested against 288 Streptococcus pneumoniae and 220 Haemophilus influenzae clinical strains isolated in our hospital from January 2005 to May 2006 by agar dilution and broth microdilution method, respectively. MICs were also determined for 13 and 10 comparison drugs, respectively. The pneumococci tested comprised 113 (39.

[Susceptibility to betalactam antibiotics, glycopeptides and aminoglycosides in commensal strains of erythromycin-resistant alpha-hemolytic streptococci and Gemella spp].

Objective: Susceptibility to seven betalactam antibiotics, glycopeptides and aminoglycosides was investigated in 190 erythromycin-resistant alpha-hemolytic streptococci and 30 Gemella spp, mainly from normal flora.

Material And Methods: Antimicrobial susceptibility testing was performed by a standard agar diffusion test and a standard agar dilution method according to NCCLS/CLSI criteria.

Results: 62.

Molecular epidemiology of macrolide and tetracycline resistances in commensal Gemella sp. isolates.

The epidemiologic relatedness of 29 erythromycin-resistant Gemella sp. strains from normal flora, characterized previously, were evaluated by pulsed-field gel electrophoresis (PFGE). Three isolates carried the tet(O) gene and the tet(M) gene.

Molecular basis of resistance to macrolides and other antibiotics in commensal viridans group streptococci and Gemella spp. and transfer of resistance genes to Streptococcus pneumoniae.

We assessed the mechanisms of resistance to macrolide-lincosamide-streptogramin B (MLS(B)) antibiotics and related antibiotics in erythromycin-resistant viridans group streptococci (n = 164) and Gemella spp. (n = 28). The macrolide resistance phenotype was predominant (59.