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Objectives Candida spp. are clinically important pathogens that cause difficulties for treatment by biofilm formation. Considering antifungal resistance rates and the limitations in the discovery of new antifungals, the antifungal and antibiofilm effects of various drugs used for different therapeutic purposes are becoming more important. The goal of our study was to determine the antifungal and antibiofilm effects of the selective serotonin reuptake inhibitors (SSRIs), namely sertraline (SRT), paroxetine (PRX), and fluoxetine (FLX) alone and in combination with fluconazole (FLC) against Candida spp. Materials and methods Twenty Candida spp. strains isolated from clinical samples from Ege University Hospital were identified by the Dalmau method and matrix-assisted laser desorption ionization time of flight mass spectrometry. The minimum inhibitory concentrations (MICs) of the SSRIs and FLC were detected by broth microdilution method. Synergistic interactions between the SSRIs and FLC were investigated by checkerboard assay. The antibiofilm effects of the SSRIs were determined by spectrophotometric microplate method. Results Among the isolates, five different Candida spp. (C. albicans, C. glabrata, C. krusei, C. tropicalis, and C.parapsilosis) were identified. The MICs of the SSRIs ranged between 16-512 μg/mL. While SRT showed the highest antifungal effect, the antibiofilm efficacy of FLX was higher than that of the other agents. Moreover, FLX and PRX showed a synergistic effect with FLC in 13 and 19 isolates, respectively. Four isolates were strong biofilm producers while nine isolates were moderate biofilm producers. C. parapsilosis strains showed higher biofilm production than the other species. At MIC/2 concentration, FLX and SRT alone inhibited mature biofilms in six and five isolates, respectively, while PRX caused increases biofilm formation in seven isolates. Conclusion This study revealed that MIC/2 concentrations of SSRIs could have antifungal and antibiofilm effects. SRT and FLX alone or in combination with antifungals may possibly have therapeutic potential for combating fungal infections.

Pseudomonas aeruginosa is one of the most important causes of hospital infections. Although different antibiotic groups are used for the treatment of P.aeruginosa infections, quinolone groups are distinguished by the advantages of oral administration. However, in recent years, resistance against members of this group has made treatment more difficult. The aim of this study was to investigate the epidemiological relationship and possible mechanisms of resistance in ciprofloxacin resistant P. aeruginosa isolates from Ege University Hospital. The identification of P.aeruginosa bacteria isolated from clinical samples in Ege University Medical Faculty Medical Microbiology Laboratory was determined by VITEK MS automated systems by VITEK compact, antimicrobial susceptibility. The epidemiological relationships of the ciprofloxacin resistant isolates were determined by Enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR). The presence of qnrA, qnrB, qnrS, qepA genes, the quinolone resistance genes and nfxB, mexR, the regulatory genes of the efflux pump, was determined by PCR. The phenylalanine-arginine β-naphthylamide (PAβN) assay was used to determine the activation of the efflux pump. Twenty-two isolates (26.5 %) were found resistant to ciprofloxacin. According to the ERIC-PCR results, 11 unrelated clones were detected. Ciprofloxacin minimum inhibitory concentration (MIC) values were decreased 2-64 times in 10 isolates in the presence of PAIN. No ciprofloxacin MIC change was detected in one isolate. The presence of pump regulatory genes was determined in 10 of the 11 representative isolates, while only qnrB of the genes associated with quinolone resistance was detected in seven representative isolates. qnrA, qnrS, qepA genes were not detected in any isolate. Ciprofloxacin resistant P.aeruginosa isolates are isolated from our hospital. It is noteworthy that the isolates belonging to different genetic groups are in circulation in clinics. Basic resistance mechanisms are thought to be efflux pumps and qnrB genes.

Klebsiella pneumoniae insan normal mikrobiyotasında yer alan, fırsatçı patojen olarak özellikle hastane enfeksiyonu yapan Enterobacteriaceae familyası üyesidir. Özellikle karbapenem grubu antibiyotiklere dirençli K.pneumoniae izolatlarının ortaya çıkması nedeniyle hastanede yatış süreleri, mortalite ve morbidite artışları gözlenmektedir. Ülkeler, bölgeler hatta sağlık kuruluşları arasında bile farklı direnç oranları gözlenmekle birlikte, son 10 yıllık dönemde karbapenem dirençli suşların oranlarında hızlı bir artış görülmektedir. Karbapenem dirençli suşların hızlı ve doğru tespiti, etken oldukları enfeksiyonların tedavisinde, uygun antibiyotik ve kombinasyonların belirlenebilmesi, başarı oranının artırılması açısından oldukça önem taşımaktadır. Bu çalışmanın amacı, karbapenem dirençli K.pneumoniae izolatlarındaki karbapenemaz varlığı ve tiplerini araştırarak, bu amaçla kullanılabilecek ticari bir ürün olan "MASTDISCS(TM) ID carbapenemase detection disc set'' ve görece yeni bir yöntem olan "Carbapenem Inactivation Method (CIM)" yöntemlerinden elde edilecek sonuçların polimeraz zincir reaksiyonu (PCR) yöntemiyle karşılaştırmasının yapılmasıdır. Bu amaçla, ertapenem, meropenem ve imipenem antibiyotiklerinden herhangi birine dirençli olduğu saptanan 2015-2016 yılları arasında izole edilen 54 K.pneumoniae izolatı çalışmaya dahil edilmiştir. İzolatların tür düzeyinde tanımlanması VITEK MS ile yapılırken, antibiyotik duyarlılık testleri ise VITEK 2 Compact® otomatize sistemi kullanılarak gerçekleştirilmiştir. Otomatize sistemde karbapenem dirençli olduğu saptanan izolatlarda gradiyent test yöntemiyle "The European Committee on Antimicrobial Susceptibility Testing (EUCAST)" önerileri doğrultusunda minimum inhibitör konsantrasyonu (MİK) değerleri belirlenmiştir. Bu izolatlarda blabla "MASTDISCS(TM) ID carbapenemase detection disc set" ve "Carbapenem Inactivation Method (CIM)" yöntemleriyle araştırılmış ve izolatların klonal ilişkisini saptamak için REP-PCR uygulanmıştır. Elli dört K.pneumoniae izolatı karbapenem dirençli olarak belirlenirken, imipenem, meropenem ve ertapenem MİK ve MİK değerleri 32 µg/ml olarak belirlenmiştir. İzolatların 33'ünde yalnız blayalnız blabla klon gözlenmiştir. "MASTDISCS(TM) ID carbapenemase detection disc set" karbapenemaz üreten izolatların tamamını saptayabilirken, metallo beta-laktamaz (MBL) ve OXA-48 enzim birlikteliği olan izolatlarda OXA-48 ayrımını yapmada yetersiz kaldığı gözlenmiştir. CIM yöntemi OXA-48 içeren izolatlarda oldukça düşük oranda (%46.15) pozitif sonuç verirken, blabaşarılı olarak bulunmuştur. Çalışmamız kapsamında, Mastdiscs-ID yönteminin, ülkemizde prevalansı yüksek olan bla, bla , bla , bla genleri PCR ile araştırılmıştır. Karbapenem dirençli izolatlarda fenotipik olarak enzim tiplendirilmesi belirlenirken, 19 izolatta her iki genin birlikte bulunduğu saptanmıştır. İzolatların hiçbirinde, , bla , bla , ikisinde genlerine rastlanmamıştır. İzolatlar REP-PCR yöntemiyle değerlendirildiğinde, altı ana içeren izolatlarda saptama oranı (%85.71) daha varlığını saptamada başarıyla kullanılabileceği sonucuna varılmıştır, Being a member of the Enterobacteriaceae family, Klebsiella pneumoniae is an opportunistic pathogen that inhabits normal human microbiota and causes predominantly hospital-acquired infections. The emergence of K.pneumoniae isolates which are resistant particularly to the carbapenem group of antibiotics has led to an increase in hospitalization period, mortality and morbidity. Although different rates of resistance are observed between countries, regions and even healthcare facilities, there has been a rapid increase in the prevalence of carbapenem-resistant strains in the last 10 years. Fast and correct identification of carbapenem-resistant strains is important for the successful treatment of infections caused by these resistant bacteria. The objective of this study was to investigate the presence and the types of carbapenemases in carbapenem-resistant K.pneumoniae strains using “MASTDISCS™ ID carbapenemase detection disc set”, a commercial product that can be used for this purpose, and “Carbapenem Inactivation Method (CIM)”, a relatively new method, and compare the results of these methods by polymerase chain reaction (PCR). For this purpose, we used 54 K.pneumoniae strains isolated in 2015-2016, that were resistant to any of the ertapenem, meropenem or imipenem antibiotics. The identification of the strains was performed using VITEK MS and their antibiotic susceptibility tests were carried out using the VITEK 2 Compact® automated system. For the strains that were found resistant to carbapenems in the automated system, the minimum inhibitor concentration (MIC) values were determined by the gradient testing method according to the recommendations of “The European Committee on Antimicrobial Susceptibility Testing (EUCAST)”. The blaOXA-48, blaIMP, blaNDM, blaVIM, and blaSIM genes were investigated with PCR among these isolates. Phenotypic enzyme typing was performed in the carbapenem-resistant strains using the “MASTDISCS™ ID carbapenemase detection disc set” and “Carbapenem Inactivation Method (CIM)”. REP-PCR was used to reveal clonal relationship of the isolates. The 54 K.pneumoniae isolates were found as resistant to carbapenem and the MIC50 and MIC90 values of imipenem, meropenem and ertapenem were 32 µg/ml. Only 33 of the strains had blaOXA-48 and two of them had only blaNDM, the remaining 19 strains had both of these two genes. The blaIMP, blaVIM and blaSIM genes were not encountered in any of the isolates. When the isolates were assessed by the REPPCR method, six main clones were detected. The “MASTDISCS™ ID carbapenemase detection disc set” was able to detect all the carbapenemase producing strains and it remained incapable of distinguishing OXA-48 in the strains which had both OXA-48 and metallo beta lactamase (MBL) enzymes. The CIM method showed a low rate of positivity (46.15%) in the strains containing blaOXA-48, but was found much more successful in the strains containing blaNDM with a detection rate of 85.71%. In this study, it was concluded that the Mastdiscs-ID method could be successfully used to detect the presence of blaOXA-48 which has a high prevalence in our country.

Objectives The aim of this study was to determine the antibiotic resistance profile, clonal relation and efficacy of antibiotic combinations in nosocomial multidrug resistant (MDR) Acinetobacter baumannii. Materials and methods Antibiotic susceptibilities of 84 MDR A. baumannii against tigecycline (TGC), colistin (CL), amikacin (AK), ciprofloxacin (CIP), meropenem (MR), moxifloxacin (MXF), rifampicin (RF) were determined by microdilution method. Clonal relationship was investigated by genotyping using AP-PCR and antibiotyping. Interactions of antibiotic combinations were tested against clonally unrelated strains by the checkerboard (CB) method. The efficacy of the best combinations was also assesed on a selected isolate by the time-kill (TK) method. Results CIP, RF, MXF, MR, AK resistance was found as 90.47%; 47.62%; 22.62%; 58.33%; 50% respectively; however; CL and TGC were not ascertained. The isolates were distinguished as 25 different antibiotypes and 15 varied molecular patterns. The best synergistic effect was detected in combinations of CL with RF (100%) and MR (100%), in combinations of TGC with RF (53%) against clonally unrelated 15 MDR A. baumannii isolates by the CB method. While CL-RF and CL-MR showed synergy by TK method like CB, on the other hand TGC-RF indicated additive interactions by TK. Conclusion In this study, both synergy tests showed that CL in combination with RF would be a good option in MDR A. baumannii.

WOS: 000435396300005, PubMed ID: 30020039, Introduction: Increased tuberculosis prevalence, and isolation of multidrug resistant (MDR) Mycobacterium tuberculosis strains frequently as causative organisms from tuberculosis infections are resulted in increasing need of new anti-tuberculosis drugs. Nowadays, fluoroquinolones known to have fewer side effects than the other drugs used in treatment of tuberculosis are sometimes assessed even as first-line anti-tuberculosis drugs due to their in vitro and in vivo strong activity. It was aimed in this study to investigate phenotypically the fluoroquinolone susceptibility in MDR and non-MDR M. tuberculosis isolates. Materials and Methods: A total of 126 MDR and non-MDR M. tuberculosis isolates from mycobacteriology laboratory of two hospitals in the Aegean Region of Turkey were included in the study. Ciprofloxacin (CIP), levofloxacin (LEV) and moxifloxacin (MXF) susceptibilities were assessed by agar proportion method according to the Clinical and Laboratory Standards Institute (CLSI) recommendations. Results: Twelve (15.2%), 5 (6.3%) and 4 (5.1%) of the MDR M. tuberculosis strains were resistant to CIP, LEV, MXF, respectively [resistance breakpoints (mu g/mL); CIP (> 2), LEV (> 1), MXF (> 0.5)] while non-MDR strains were susceptible to CIP, LEV, MXF. Conclusion: Consequently, although high fluoroquinolone susceptibilities were evaluated as a pleasing data in this study, to preserve their efficiency for many years steadily, quinolone usage and resistance increment in MDR M. tuberculosis isolates should be monitored elaborately., Ege University Scientific Research Projects Foundation (EGE-BAP) Committee [06-ECZ-007], Authors would like to thank to Ege University Scientific Research Projects Foundation (EGE-BAP) Committee for their financial supports (Project Number: 06-ECZ-007).

The emergence of phenotypic resistance to ciprofloxacin and levofloxacin in methicillin-sensitive and methicillin-resistant Staphylococcus aureus (MRSA) strains was studied. Twenty MRSA and 77 methicillin-sensitive S.aureus (MSSA) strains susceptible to both quinolones were investigated for resistance after single step or serial passages. No growth of 20 MRSA strains was observed at 4×MIC of levofloxacin after 48 h incubation, but 4 of 77 (5%) MSSA strains grew at the same concentration. At 4×MIC concentration of ciprofloxacin, 10 MSSA (13%) and five MRSA (25%) strains were grown. In the serial passages of MRSA strains, resistance to ciprofloxacin was 75 and 5% for levofloxacin by the third passage. In the seventh passage this resistance was 100 and 15%, respectively. In MSSA strains, resistance to ciprofloxacin was 75 and 19% to levofloxacin at the third passage and at the seventh passage, 100 and 61%, respectively. Emergence of ciprofloxacin resistance was more common and developed more rapidly than resistance to levofloxacin in both MRSA and MSSA strains. © 2003 Elsevier Science B.V. and the International Society of Chemotherapy. All rights reserved.

WOS: 000365565100012, PubMed ID: 25303196, Objective: Stenotrophomonas maltophilia is an opportunistic pathogen found predominantly in the enviroment and hospital setting. Invasive procedures and treatment methods, instruments used for diagnosis and irrational antibiotic use play major roles in the spread of this pathogen. The study aimed to evaluate consecutive S maltophilia isolation from bronchoalveolar lavage samples during bronchoscopy procedure during a week. Methods: Four patients consecutively had S maltophilia isolated during bronchoscopy between September 8 and 15, 2012. The identification of the isolates and their antibiotic susceptibility were studied by automated Vitek version 2.0 (Biomerieux, France) system. The clonal relationship between the isolates was studied by enterobacterial repetitive intergenic consensus (ERIC) polymerase chain reaction (PCR). Results: Four consecutive S maltophilia isolates had identical band patterns and showed clonal relatedness. Conclusion: Bronchoscopy is a common invasive procedure that is utilized in chest diseases departments and intensive care units (ICUs). Contamination may take place due to inappropiate use and cause spread of infectious pathogens. In the current study, we detected consecutive S maltophilia strains with identical band patterns isolated within a week. After appropiate disinfection and cleaning procedures, no further isolation was detected.

Acinetobacter baumannii, ventilatörle ilişkili pnömoni, bakteriyemi, menenjit, üriner sistem ve yara enfeksiyonları gibi insan sağlığını tehdit eden önemli nozokomiyal enfeksiyonlara neden olan fırsatçı bir patojendir. Çok ilaca dirençli (ÇİD) A.baumannii suşlarının neden olduğu enfeksiyonlarda tedavi seçenekleri oldukça kısıtlıdır. Günümüze kadar A.baumannii izolatlarıyla yapılan çalışmaların çoğu antibiyotik direnci, tedavi protokolleri ve epidemiyolojik veriler üzerine odaklanmasına karşın, bu bakterinin virülans faktörleriyle ilgili çalışmaların sayısı azdır. Biyofilm oluşturma, serum direnci, hareket, efluks pompası ve demir kazanımı gibi özellikler, bakterinin olumsuz ortam koşullarında hayatta kalmasını ve enfeksiyon oluşturmasını kolaylaştırmaktadır. Bu çalışmada, klinik önemi gittikçe artan ÇİD A.baumannii izolatlarının virülansıyla ilişkili temel özelliklerin araştırılması hedeflenmiştir. Çalışmaya, Ege Üniversitesi Tıp Fakültesi, Tıbbi Mikrobiyoloji Anabilim Dalında Aralık 2011-Mart 2012 tarihleri arasında çeşitli klinik örneklerden izole edilen, siprofloksasin-imipenem-trimetoprim/sülfametoksazole dirençli 65 A.baumannii suşu alınmıştır. İzolatların klonal yakınlıkları, “Enterobacterial repetitive intergenic consensus (ERIC)” dizilerine özgü ERIC-2 primeri kullanılarak PCR ile incelenmiştir. Her klondan bir temsilci seçilerek, bu suşlarda biyofilm oluşturma, siderofor üretimi, serum direnci, “twitching (seğirme)” ve “swarming (yayılma)” hareketleri ile efluks pompası varlığı araştırılmıştır. Çalışmaya alınan ÇİD A.baumannii suşlarının yedi ana grup altın- da toplandığı, bu klonlardan en büyüğünün incelenen izolatların %86’sını kapsadığı belirlenmiştir. Alt gruplar da dahil olacak şekilde tüm klonlardan temsili birer suş alınarak, toplam 16 bakteride virülansla ilişkili özellikler araştırılmıştır. Biyofilm oluşturma kapasitesi incelenen bu suşlardan 12’sinin güçlü, üçünün orta, birinin ise zayıf biyofilm üreticisi olduğu belirlenirken, hiçbir suşta siderofor üretimi saptanamamış- tır. On altı suştan ikisinin, serumun bakterisidal etkisine dirençli, birinin orta duyarlı, 13’ünün ise duyarlı olduğu bulunmuştur. Çalışmamızda, sadece bir suşta “twitching”, yedi suşta ise “swarming” hareketi gözlenmiştir. “Twitching” görülen izolatta aynı zamanda “swarming” de saptanmıştır. Siprofloksasin ile efluks pompası varlığı araştırılan 16 suştan hiçbirinde bu yönde bir bulguya rastlanmazken, doksisikline dirençli beş suştan ikisinde efluks pompası tespit edilmiştir. İncelenen suşlarda, biyofilm oluşturmanın en yaygın gözlenen özellik olduğu, bunun yanı sıra serum direnci, “swarming” hareketi ve spektrumunda tetrasiklinleri içeren bir efluks pompasının da virülansla ilişkili özellikler arasında yer aldığı belirlenmiştir. Biyofilm oluşumuna tüm klonlarda, serum direncine ise sadece en baskın klonun temsilcilerinde rastlanmıştır. Hareket ve efluks pompası varlığı ise belirli bir klona özgü değildir. Hastanemizde olduğu gibi tüm dünyada nozokomiyal enfeksiyonların en önemli etkenlerinden olan ÇİD A.baumannii izolatlarının patojenitesinde rol oynayan özelliklerin ortaya konması, gerekli enfeksiyon kontrol önlemlerinin alınması ve yeni tedavi seçeneklerinin araştırılmasında yol gösterici olacaktır., Acinetobacter baumannii is an opportunistic human pathogen which causes life-threatening nosocomial infections such as ventilator-associated pneumonia, bacteremia, meningitis, urinary tract and wound infections. Treatment options are very limited for infections caused by multi-drug resistant (MDR) A.baumannii strains. Until recently, the majority of studies related to A.baumannii have focused on antibiotic resistance, treatment protocols and epidemiological data, however, there have been few studies addressing the virulence factors of this organism. The features such as biofilm formation, serum resistance, motility, efflux pumps and iron acquisition mechanisms help the bacterium to survive in adverse environmental conditions and facilitate the development of an infection. The aim of the present study was to investigate the basic characteristics that contribute to the virulence of clinically important MDR A.baumannii isolates. Sixty-five ciprofloxacin-imipenem-trimethoprim/sulfamethoxazole-resistant A.baumannii strains isolated from various clinical specimens between December 2011 and March 2012 at Ege University Faculty of Medicine, Department of Medical Microbiology were included in the study. The clonal relationship of the isolates was analyzed by PCR using Enterobacterial repetitive intergenic consensus (ERIC)-2 primer. Biofilm formation, serum resistance, twitching and swarming motility, efflux pump and siderophore production were sought in representatives of each clone. Investigated MDR A.baumannii isolates were classified into seven main clusters, and the largest cluster included 86% of the strains. The virulence-associated features were investigated in 16 representative strains, including sub-groups. Twelve, three and one of the examined strains were determined to be strong, intermediate and weak biofilm producers, respectively. Siderophore production was not encountered in any of the isolates. Of the sixteen strains, two, one and thirteen isolates were found to be resistant, moderately susceptible and susceptible to bactericidal effect of serum, respectively. In our study, swarming motility was observed in seven strains while twitching motility was observed in only one strain. Swarming was simultaneously detected with twitching in one isolate. The presence of an efflux pump was investigated with ciprofloxacin in 16 representative strains but none of them were positive. However, eflux pump was determined in two of the five doxycycline resistant strains. Biofilm production was the most commonly observed characteristic among the examined strains. In addition, serum resistance, swarming and an efflux pump which has a spectrum including tetracyclines, were also determined among features associ- ated with virulence. While the biofilm production was encountered at the members of all clones, serum resistance was found only in the representatives of the most dominant clone. Motility and the presence of an efflux pump were not associated with a particular clone. MDR A.baumannii strains are among the most important agents of nosocomial infections in our hospital and all over the world. Revealing the characteristics that play a role in the pathogenesis of these isolates, will contribute to infection control measures and to the investigation of new treatment options.