Macrolide Resistance Determinants of Invasive and Noninvasive Group B Streptococci in a Turkish Hospital

Macrolide resistance in 156 consecutive group B streptococcal isolates was investigated. Thirty-five isolates (22.4%) had inducible (80%) or constitutive (20%) erythromycin resistance. The genes responsible were erm(B), erm(A) subclass erm(TR), and erm(B) plus erm(TR) in 62.9, 2.9, and 8.6% of isolates, respectively. Nine isolates (25.7%) harbored neither mef nor detectable erm genes

Risk factors for infection with colistin-resistant gram-negative microorganisms: a multicenter study

WOS: 000384907900008PubMed ID: 27236394BACKGROUND: Knowing risk factors for colistin resistance is important since colistin is the only remaining choice for the treatment of infections caused by multi-drug resistant microorganisms. OBJECTIVE: Evaluate risk factors associated with infection by colistin-resistant microorganisms. DESIGN: Retrospective study. SETTINGS: Tertiary healthcare centers. PATIENTS AND METHODS: An e-mail including the title and purpose of the study was sent to 1500 infectious disease specialists via a scientific and social web portal named "Infeksiyon Dunyasi (Infection World)". Demographic and clinical data was requested from respondents. MAIN OUTCOME MEASURE(S): Colistin-resistance. RESULTS: Eighteen infectious disease specialists from twelve tertiary care centers responded to the invitation. Data was collected on 165 patients, 56 cases (39.9%) and 109 (66.0%) age-and sex-matched controls. The colistin-resistant microorganisms isolated from cases were 29 Acinetobacter baumannii (51.8%), 18 Pseudomonas aeruginosa (32.1%) and 9 Klebsiella spp. Colistin, carbapenem, and quinolone use in the last three months were risk factors for colistin resistance in the univariate analysis. Previous quinolone use in the last three months (P=.003; RR: 3.2; 95% CI: 1.5-6,7) and previous colistin use in the last three months (P=.001; RR: 3.6; 95% CI: 1.63-7.99) were significant risk factors in the multivariate analysis. CONCLUSION: Clinicians should limit the use of quinolones and remain aware of the possibility of resistance developing during colistin use. LIMITATIONS: The lack of a heteroresistance analysis on the isolates. No data on use of a loading dose or the use of colistin in combination

A Prospective Multicenter Study On The Evaluation Of Antimicrobial Resistance And Molecular Epidemiology Of Multidrug-Resistant Acinetobacter Baumannii Infections In Intensive Care Units With Clinical And Environmental Features

Background Multidrug-resistant (MDR) Acinetobacter baumannii infections are considered as emerging nosocomial infections particularly in patients hospitalized in intensive care units (ICUs). Therefore, reliable detection of MDR strains is crucial for management of treatment but also for epidemiological data collections. The purpose of this study was to compare antimicrobial resistance and the clonal distribution of MDR clinical and environmental A. baumannii isolates obtained from the ICUs of 10 different hospitals from five geographical regions of Turkey in the context of the demographic and clinical characteristics of the patients. Methods A multicenter-prospective study was conducted in 10 medical centers of Turkey over a 6 month period. A total of 164 clinical and 12 environmental MDR A. baumannii isolates were included in the study. Antimicrobial susceptibility testing was performed for amikacin (AN), ampicillin–sulbactam (SAM), ceftazidime (CAZ), ciprofloxacin (CIP), imipenem (IMP) and colistin (COL) by microdilution method and by antibiotic gradient test for tigecycline (TIG). Pulsed-field gel electrophoresis (PFGE) was performed to determine the clonal relationship between the isolates. The detection of the resistance genes, blaOXA-23, blaOXA-24, blaOXA-51, blaOXA-58, blaIMP, blaNDM, blaKPC, blaOXA-48 and blaPER-1 was carried out using the PCR method. Results The mortality rate of the 164 patients was 58.5%. The risk factors for mortality included diabetes mellitus, liv1er failure, the use of chemotherapy and previous use of quinolones. Antimicrobial resistance rates for AN, SAM, CAZ, CIP, IMP, COL and TIG were 91.8%, 99.4%, 99.4%, 100%, 99.4%, 1.2% and 1.7% respectively. Colistin showed the highest susceptibility rate. Four isolates did not grow on the culture and were excluded from the analyses. Of 172 isolates, 166 (96.5%) carried blaOXA-23, 5 (2.9%) blaOXA-58 and one isolate (0.6%) was positive for both genes. The frequency of blaPER-1 was found to be 2.9%. None of the isolates had blaIMP, blaKPC, blaNDM and blaOXA-48 genes. PFGE analysis showed 88 pulsotypes. Fifteen isolates were clonally unrelated. One hundred fifty-seven (91.2%) of the isolates were involved in 14 different clusters. Conclusions Colistin is still the most effective antibiotic for A. baumannii infections. The gene blaOXA-23 has become the most prevalent carbapenemase in Turkey. The distribution of invasive A. baumannii isolates from different regions of Turkey is not diverse so, infection control measures at medical centers should be revised to decrease the MDR A. baumannii infections across the country. The results of this study are expected to provide an important baseline to assess the future prophylactic and therapeutic options.PubMedWoSScopu

Risk factors for infection with colistin-resistant gram-negative microorganisms: a multicenter study

BACKGROUND: Knowing risk factors for colistin resistance is important since colistin is the only remaining choice for the treatment of infections caused by multi-drug resistant microorganisms. OBJECTIVE: Evaluate risk factors associated with infection by colistin-resistant microorganisms. DESIGN: Retrospective study. SETTINGS: Tertiary healthcare centers. PATIENTS AND METHODS: An e-mail including the title and purpose of the study was sent to 1500 infectious disease specialists via a scientific and social web portal named ``Infeksiyon Dunyasi (Infection World){''}. Demographic and clinical data was requested from respondents. MAIN OUTCOME MEASURE(S): Colistin-resistance. RESULTS: Eighteen infectious disease specialists from twelve tertiary care centers responded to the invitation. Data was collected on 165 patients, 56 cases (39.9\%) and 109 (66.0\%) age-and sex-matched controls. The colistin-resistant microorganisms isolated from cases were 29 Acinetobacter baumannii (51.8\%), 18 Pseudomonas aeruginosa (32.1\%) and 9 Klebsiella spp. Colistin, carbapenem, and quinolone use in the last three months were risk factors for colistin resistance in the univariate analysis. Previous quinolone use in the last three months (P=.003; RR: 3.2; 95\% CI: 1.5-6,7) and previous colistin use in the last three months (P=.001; RR: 3.6; 95\% CI: 1.63-7.99) were significant risk factors in the multivariate analysis. CONCLUSION: Clinicians should limit the use of quinolones and remain aware of the possibility of resistance developing during colistin use. LIMITATIONS: The lack of a heteroresistance analysis on the isolates. No data on use of a loading dose or the use of colistin in combination