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Objective: Our objective was to investigate the antimicrobial susceptibilities of Escherichia coli isolated from urinary cultures in Central Laboratory of Hacettepe University Faculty of Medicine Hospital and to examine the differences between antimicrobial susceptibilities of E. coli isolated from different patient groups. Methods: E. coli isolated from urinary cultures between January 1, 2017 and April 30, 2018 were included in our study. Automated systems, i.e. VITEK® 2 Compact (bioMérieux, Marcy l'Etoile, France) and BD Phoenix (Becton Dickinson, Sparks, MD, USA) and disk diffusion test were used for the determination of antimicrobial susceptibilities. The patients from whom the bacteria were isolated were divided into groups according to age (<18 years, 18-64 years, and >64 years), gender and patient care (outpatients/inpatients). Results: The highest susceptibility rates were observed for carbapenems (>99%), fosfomycin (98.5%), nitrofurantoin (98.3%) and amikacin (94.2%), whereas the highest resistance rates were observed for ampicillin (61.3%) and amoxicillin--clavulanate (37.5-45.7%). Antimicrobial resistance rates of isolates from patients aged 65 years and over were higher than those of patients in other age groups, with the exception of piperacillintazobactam, amikacin and ertapenem. The resistance rates of isolates belonging to male patients were higher than those belonging to female patients for all antimicrobials. Also, the resistance rates of isolates belonging to inpatients were higher than those belonging to outpatients for all antimicrobials. When the rates of extended-spectrum-lactamase (ESBL)-producing E. coli from different age groups were compared, the highest rate (34.2%) was observed among the isolates from patients aged 65 years and over. The rates of ESBL-producing E. coli from males (33.9%) and inpatients (36.3%) were higher than those from females (23.8%) and outpatients (23.3%), respectively. Conclusions: Antimicrobial susceptibilities of E. coli isolates may vary among different patient groups. Demographic features of patients may guide for selecting the antimicrobials for empiric treatment of urinary tract infections. [ABSTRACT FROM AUTHOR]

Objective: Production of extended-spectrum β-lactamases (ESBLs) is the most important antimicrobial resistance mechanism among Gram-negative pathogens. In this study, ESBL frequency and antimicrobial resistance of Escherichia coli and Klebsiella spp. isolated from community-acquired urinary tract infections (UTIs) are investigated. Methods: In this retrospective cross-sectional study, ESBL rates and the results of antimicrobial susceptibility tests were determined for E. coli and Klebsiella spp. grown in the urine cultures of 520 patients with community-acquired UTI, and the changes in the antimicrobial resistance rates of the isolates were compared in terms of ESBL production. Results: E. coli had grown in 220 samples and Klebsiella spp. in 38 samples. ESBL production frequencies of the isolates were found as 40% and 47.4%, respectively, and the rate of carbapenem resistance was found as 3.1%. Among the isolates, the highest resistance was found for amoxicillin-clavulanate (46%), ciprofloxacin (44.9%), and ceftriaxone (42.2%), while the lowest resistance was found for colistin (0.3%), fosfomycin (1.5%), amikacin (3.1%), and nitrofurantoin (4.2%). In ESBL-producers, significantly higher resistance was found for all antibiotics studied, except colistin, nitrofurantoin and fosfomycin. Conclusions: In this study, it was shown that almost half of the community-acquired isolates were ESBL-producers, and these isolates had acquired resistance against many antimicrobials including the last resorts such as carbapenems and colistin. To reduce the progress of resistance rates in E. coli and Klebsiella spp. which are the most common pathogens in community-acquired UTIs, their therapies should be planned according to the results of susceptibility tests as much as possible. [ABSTRACT FROM AUTHOR]

Objective: Recommended combination for the treatment of serious Stenotrophomonas maltophilia infections is ticarcillinclavulanate and co-trimoxazole (SXT). However, first agent is not available in our country, and the second component may be a matter of antimicrobial resistance or intolerance. Therefore, we aimed to evaluate antimicrobial susceptibility testing results of S. maltophilia and in vitro activity of ceftazidime and moxifloxacin as a potential therapeutic alternative. Methods: S. maltophilia strains isolated from clinical samples in Infectious Diseases and Clinical Microbiology Laboratory between 1 October 2007-23 November 2017 were included in the study. Disk diffusion antimicrobial susceptibility test results of the strains were evaluated retrospectively. The in vitro activity of combination of ceftazidime and moxifloxacin against 24 of these strains was investigated by Etest®. Results: During the study period, 649 S. maltophilia strains were isolated from 649 different patients, and 94%, 93%, 92%, 81%, 60%, 55%, 45%, 41%, 38% of the strains were susceptible to tigecycline, moxifloxacin, SXT, ciprofloxacin, cefoperazonesulbactam, ceftazidime, netilmicin, gentamicin and amikacin, respectively. For the 24 strains included in the combination study, the moxifloxacin minimal inhibitory concentration (MIC)50/MIC90 values were defined as 0.064/0.125 µg/mL (MIC range 0.023-4 µg/mL) and ceftazidime MIC50/MIC90 values were defined as 32/256 µg/mL (MIC range 1.5-256 µg/mL). According to the results of fractional inhibitor concentration (FIC) index; ceftazidime and moxifloxacin combination displayed synergism, additivity and indifference for 1 (4%), 18 (75%) and 5 (21%) strains, respectively and there was no antagonism. The FIC50/ FIC90 value is calculated as 0.75/1.01 (FIC range 0.5-1.01). Conclusions: SXT resistance in S. maltophilia strains is below 10%, but it should be closely monitored because of the limited treatment options. Tigecycline and moxifloxacin can be among the treatment alternatives because of their high sensitivity rates similar to SXT. The combination of moxifloxacin plus ceftazidime demonstrated in vitro synergism or additivity against majority of the strains. So, this combination may be used as an alternative for the treatment of patients with S. maltophilia infections if there is resistance or side effects to the antibiotics used as the first option. [ABSTRACT FROM AUTHOR]

Chronic suppurative otitis media was diagnosed in a 30-year old female with left ear pain and ear discharge lasting since 5 years intermittently. Lactose-negative, oxidase-negative, Gram-negative small bacilli grown as flat and gray colonies with smooth margins were identified as Kerstersia gyiorum by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and 16S rRNA analysis. Minimum inhibitory concentration values were determined by broth microdilution method (ciprofloxacin >2 µg/mL, ertapenem <0.25 µg/mL, imipenem 0.5 µg/mL, ceftazidime 2 µg/mL, amikacin ≤4 µg/mL, ceftriaxone ≤0.5 µg/mL, gentamicin 2 µg/mL and tigecycline 1 µg/mL). It was learned that her clinical findings resolved by oral amoxycillin-clavulanic acid and topical ciprofloxacin given empirically. [ABSTRACT FROM AUTHOR]

Objective: Urinary Tract Infections (UTI) are most common causes of bacterial infections in humans. Escherichia coli (E.coli) is the most frequently isolated microorganism in cases of uncomplicated UTI. In this study, we aimed to determine antimicrobial resistance patterns of E.coli strains isolated from patients with UTI. Materials and Methods: E.coli strains isolated from urine cultures of patients admitted to the Hospital of the Medical Faculty of Bezmialem Vakif University were retrospectively evaluated between the dates of January 2013 and December 2013. The bacterial identification and rates of antibiotic resistance were determined using VITEK-2 automatized system. Results: E.coli isolates were found to have low resistance rates to fosfomycin (0.6%), nitrofurantoin (5.3%) and amikacin (8%). Among the other antibiotics, the lowest susceptibility rates were detected to ampicillin (64%), trimetoprim/sulfomethoxazole (43.2%), amoxicillin/clavulonic acid (32.8%). Conclusion: Fosfomisin, nitrofurantoin and amikacin are thought to be suitable antimicrobial agens in the empiric treatment treatment of uncomplicated UTI. [ABSTRACT FROM AUTHOR]