Introduction: Blood stream infections (BSIs)are the most frequent causes of mortality and the morbidity in immunosupressive patients as solid organ transplant recipients. Particularly antimicrobial resistant pathogens are one of the major challenges in these patient group. Timing of appropriate emprical antimicrobial treatment is lifesaving and knowing the change of  local microbial distribution and antimicrobial resistance patterns in years  is crucial for updating  emprical treatment decision.
Materials and Methods: The data was collected retrospectively from  143 solid organ transplantation recipients  BSI episodes occured in 2009 and in 2019.  We analysed the distribution and resistance patterns of isolates between the 2009 and 2019 years. The aim of our study was to evaluate the emerging of antimicrobial resistanceduring this time period   in this patient group
Results: In our study there were 57 BSI isolates in 2009 and 86 BSI  isolates in 2019. Gram negative pathogens were the most common isolates for both periods; however,  the ratio of gram negatives had decreased from 60% to 49%. While the ratio decreased, the  resistance in gram negatives had increased. Klebsiella isolates became the most common gram negative pathogens and  extended spectrum beta lactamase (ESBL) pruduction and carbapenem resistance in Klebsiella spp. increased from 52% to 72%, and 25% to 36% respectively. The carbepenem resistance in Acinetobacter spp. had risen from 60% to 100% between 2009 to 2019. While there were no methicillin resistance in S.aureus isolates in 2009, 7 of 9 isolates are found resistant to methicillin in 2019. We found only one vancomycin resistant Enterococcus spp. in 2019.
Conclusion: Antimicrobial  resistance rates are rising year after year all around the world. Resistance to broad spectrum animicrobials like carbapenems, limits the treatment choices of critical infections in immunocompromised patients . The knowledge of distribution and resistance patterns of isolates provides infectious diseases specialists and transplantation teams effective administration of emprical antimicrobial treatment. Therefore, all centers have to fallow their local data.