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Objective: The causative microorganisms and their antibiotic susceptibility in bacteremia vary according to the centers and years. These changes should be identified in order to guide empirical treatment. In this study, it was aimed to investigate the general distribution and antibiotic susceptibility of microorganisms isolated from blood cultures of patients in intensive care units. Methods: Microorganisms isolated from blood cultures from the intensive care units of Niğde Training and Research Hospital between March 2019 and March 2021 were evaluated retrospectively. Blood samples were studied in the BD BACTEC FX (Becton Dickinson, USA) automated blood culture system and the identification and antibiotic susceptibility tests of the isolated bacterial and fungal strains were performed with the Vitek 2 compact (BioMérieux, France) automated system. Results: A positivity was detected in 995 of a total of 9607 blood culture bottles. Among the isolated microorganisms, Gram positive bacteria were 71.7% (713/995), Gram negative bacteria 27.2% (271/995), yeast 1.1% (11/995). Among all microorganisms, the most common coagulase negative staphylococcus (CNS) 58.9% (586/995), Acinetobacter baumannii 10.0% (100/995), Klebsiella pneumoniae 7.6% (76/995), Enterococcus faecium 4.1% (41/995), Escherichia coli found in 3.8% (38/995). Among the Gram positive bacteria, the most common coagulase negative staphylococci were 82.4% (586/711), and the most common Gram negative bacteria was A. baumannii 36.9% (100/271). Methicillin resistance was found in 89.8% of CNS and 57.1% in S. aureus. Vancomycin resistance in KNS, S. aureus and Enterococcus spp. was determined as 4.4%, 3.6% and 16.0%, respectively. ESBL positivity was 68.4% in E. coli and 87.0% in K. pneumoniae. While the most effective antibiotics against E. coli are meropenem (100%), colistin (100%), amikacin (100%), tigecycline (94.7%), the most effective antibiotics against K. pneumoniae are gentamicin (53.2%), amikacin (51.9%), tigecycline (48.1%) and colistin (46.8%). The most effective antibiotics against Pseudomonas aeruginosa were colistin (100%) and amikacin (69.0%), while the most effective antibiotics against A. baumannii were tigecycline (100%) and colistin (96%). Among the yeast fungi, Candida parapsilosis was found in 63.6% (7/11), Candida albicans 27.3% (3/11). Resistance to fluconazole was not detected in Candida species. Conclusion: Isolation of methicillin resistant staphylococci and enterococci, A. baumannii, P. aeruginosa, E. coli and K. pneumoniae strains showing multiple antibiotic resistance from blood cultures of patients hospitalized in our hospital's intensive care units; showed that infection control programs and rational antibiotic use policies should be made more effective. [ABSTRACT FROM AUTHOR]

Objective: In this study, the aim was to investigate the clonal relationship between carbapenem resistant Acinetobacter baumannii isolates and carbapenem resistance genes isolated from blood samples of patients followed in intensive care units by molecular methods. Methods: Bactec 9240 system (Becton Dickinson, USA) was used for the isolation of bacteria from blood culture flasks. Identification of 112 strains included in the study were performed by conventional tests, API 20NE (bioMèrieux, France) and Phoenix TM 100 system (Becton Dickinson, USA) and confirmed by the presence of blaOXA-51 gene. Antimicrobial susceptibility tests were performed by Kirby-Bauer disk diffusion method and Phoenix TM 100 system. Carbapenem resistance genes; blaOXA-23, blaOXA-48, blaOXA-58, blaIMP, blaVIM and blaNDM-1 were investigated by Multiplex Polymerase Chain Reaction (PCR) method. Pulsed Field Gel Electrophoresis (PFGE) was used to determine the clonal relationship between Acinetobacter baumannii strains. Results: The antibiotic resistance percentages of strains for gentamicin, amikacin, tobramycin, netil micin, ceftazidime, trimethoprim/sulfamethoxazole, siprofloksasin, ampisilin/sulbaktam, piperasilin/tazobaktam ve sefoperazon/sulbaktam için sırasıyla %88; %81; %78; %36; %98,5; %96; %89; %100; %100; %93; %91 olarak bulundu. İmipenem ve meropenem MİK değerleri tüm grupta =8 µg/mL'nin üzerinde saptandı. Çalışmaya alınan izolatların tümünde blaOXA-51 ve blaOXA-23 gen varlığı tespit edildi. PFGE yöntemi ile 62 farklı pulsotip saptandı. Pulsotiplerden 19 tanesi birbiriyle ayırt edilemez profil gösteren (eşittir üzeri) =2 suş içermekteydi. Toplam 108 (%96,4) suşun (benzerlik oranı pulsotipler için %85 ve üzeri kabul edildiği durumda) klonal yönden ilişkili 11 grup içerisinde toplandıkları gözlendi. Sonuç: Bu çalışmada, karbapenem dirençli A. baumannii suşlarının netilmisin dışında çalışılan tüm antibiyotiklere çok yüksek yüzdelerle dirence sahip olduğu ve hastane içinde çapraz bulaş yoluyla yayıldığı gösterildi. Bu suşlar hastane enfeksiyonları açısından risk oluşturmaktadır, bunula birlikte klonal yönden ilişkili suşlar spesifik bir ünite ve zaman periyodu ile sınırlı değildir. [ABSTRACT FROM AUTHOR]