Original Article

Evaluation of microorganisms isolated from blood cultures and their susceptibility to antibiotics in two year period

10.5455/gulhane.24245

  • Soner Yılmaz
  • Ramazan Gümral
  • Mustafa Güney
  • Orhan Bedir
  • Aylin Üsküdar Güçlü
  • Serhat Duyan
  • Ahmet Celal Başustaoğlu

Received Date: 10.08.2012 Accepted Date: 24.11.2012 Gulhane Med J 2013;55(4):247-252

Bloodstream infections (BSIs) are a major cause of healthcare-associated morbidity and mortality. Analyses of the frequency of microorganisms isolated from blood cultures and antibiotic susceptibility can provide clinicians with relevant information for the empirical treatment of patients. The purpose of the study was to investigate to frequency of microorganisms isolated from blood cultures and their sensitivity to antimicrobial agents between January 2009 and December 2010 at the Training Hospital of Gulhane Military Medical Faculty. Blood cultures were processed by automatized BACTEC/9050 (Becton Dickinson, Maryland, USA). The observed growth of microorganisms in culture media was identified by conventional methods and PhoenixTM 100 automatized systems (BD Phoenix System, Beckton Dickinson, USA). Antimicrobial susceptibility tests were performed by Kirby-Bauer disc diffusion method and automatized systems (BD Phoenix System, Beckton Dickinson, USA) in accordance with the recommendations of Clinical and Laboratory Standarts Institute (CLSI). In the study period among the 6823 blood culture samples, 957 (14%) yielded positive results. Results of 600 (8.7%) blood culture samples evaluated as contamination. Of the 957 isolated microorganisms, 61.0% were Gram negative, 31.1% were Gram positive and 7.8% were yeast. E.coli was the most frequently isolated species (15.9%), followed by Klebsiella spp (15.4%) and Coagulase Negative Staphylococcus (CNS) (13.2%). Twenty eight percent% of S. aureus and 89% of CNS isolates were resistant to methicillin. Only one isolate (1.73%) was resistant to glycopeptides among Enterococcus spp. ESBL (Extended-spectrum beta lactamase) was detected in 36.8% of E.coli and 51.3% of Klebsiella spp. isolates.

Keywords: Blood culture, antibiotics susceptibility, blood stream infectious.