Organisms Isolated from Blood Cultures, Their Antimicrobial Susceptibilities and Patient Characteristics in Patients with Febrile Neutropenia

Objective: Appropriate and prompt treatment of infections in patients with neutropenia influences the morbidity and mortality. For this purpose, information about etiological agents is of great importance. The objective of this study is to detect the organisms isolated from blood cultures, their antimicrobial susceptibilities, and patient characteristics in patients with haematological malignancy during their febrile neutropenic episodes. Methods: Febrile neutropenic patients with hematologic malignancies were evaluated retrospectively. The automated BacT/ALERT (R) 3D (bioMerieux, France) system was used for blood cultures. Antimicrobial susceptibility testing was performed as recommended by the Clinical Laboratory Standards Institute using disk diffusion method. Infections causing bacteremia were defined as primary bloodstream infections, urinary tract infections, soft tissue infections, nosocomial pneumonia, and catheter-related bloodstream infections. Results: 45 bacteremic episodes in 37 cancer patients with febrile neutropenia were evaluated in this study. Overall, 73% of the episodes were caused by Gram-negative bacili, and 27% by Gram-positive coci. The isolates were Escherichia coli (34%) Klebsiella pneumoniae (30%), coagulase-negative staphylococci (16%), Staphylococcus aureus (11%), Enterobacter spp. (4%), Serratia spp. (2%), and other Gram-negative enteric bacilli (2%) in order of frequency. Causative agents showed the highest rate of antimicrobial resistance to ciprofloxacin and piperacillin-tazobactam. The lowest rate of antimicrobial resistance were observed to amikacin and carbapenems. Conclusions: The most frequent isolates were E. coli and K. pneumoniae, and the most frequent infection was urinary tract infection in patients with febrile neutropenia. Therefore, a particular consideration has to be given to the uropathogens and their antimicrobial susceptibilities in empirical treatment.