Bacteriological etiology and antibiotic resistance patterns ofbloodstream infections in a tertiary care hospital in the southwest of Iran

Background and Aim : Since bloodstream infections have various etiologic factors and theimportance of using proper antibiotics for these infections, identifying the causative agents andantibiotic resistance patterns of isolated bacteria is critical. The present study aimed to assess theprevalence and antibiotic resistance patterns of bacteria collected from the different wards of ImamKhomeini Hospital in Ahvaz, in the southwest of IranMethods : This cross-sectional study was conducted in different wards of Imam KhomeiniHospital from April ۲۰۱۶ to March ۲۰۱۷ on hospitalized patients with suspected bloodstreaminfections. Bacteriological identification and antimicrobial susceptibility testing were performedaccording to standard methods.Results : During the study period, ۵۰۲۳ blood samples from clinically suspected cases of BSI wereobtained. Of these, ۲۶۴ bacterial isolates including ۸۷ (۳۳%) gram-positive and ۱۷۷ (۶۷ %) gramnegativeisolates were recovered. The most common gram-positive bacteria isolates wereStaphylococcus aureus ۳۳ (۱۲.۵%) followed by Enterococcus spp ۲۰ (۷.۵%), Streptococcus sppwith an isolation rate of ۱۳ (۴.۹%), and among gram-negative bacterial isolates, the mostpredominant isolates were Acinetobacter baumanii ۴۶ (۱۷.۴%) followed by E. coli ۴۰ (۱۵.۱%),Klebsiella pneumoniae ۲۸ (۱۰.۶%), Pseudomonas aeruginosa ۲۷ (۱۰.۲%), and Stenotrophomonasmaltophilia ۲۷ (۱۰.۲%).About ۵۱.۵% of Staphylococcus aureus isolates were methicillin–resistant.About ۵۰% of Enterococcus spp isolates were resistant to vancomycin. All the isolates ofStaphylococcus aureus, CoNS, Micrococcus spp, and Streptococcus spp were susceptible tovancomycin. The maximum non-fermenting gram-negative bacilli (GNFB) resistant rates wereobserved for Cefepime, Cefazolin, and Ceftriaxone. In the case of E. coli, the highest resistancerates were ۱۰۰% and ۸۵% for Ceftazidime and Cefazolin, respectively. ۱۰۰% of Klebsiellapneumoniae and Enterobacter aerogenes were resistant to Tazobactam-piperacillin andCeftazidime.Conclusion : Our results highlight the value of identifying the etiologic factors responsible forbloodstream infections and their antimicrobial resistant patterns that may provide necessaryinformation for effective antimicrobial stewardship programs in hospitals.

کلیدواژه ها:

Bloodstream Infections ، Etiology ، Iran ، Antibiotic Resistance