Investigation of Carbapenem-Resistant Acinetobacter Baumannii Resistance Rate in Clinical Specimens of Newborns at Imam Khomeini Hospital in Tehran

Background: Carbapenem-resistant Acinetobacter baumannii (CRAB), as one of the important causes of hospital acquired infections, poses a serious problem for the newborns at neonatal intensive care units (NICU). The present study was conducted to evaluate the prevalence of infections with CRAB at NICU at Imam Khomeini hospital in Tehran. Materials and Methods: The blaOXA-51-like gene was targeted among the isolates using PCR to identify the isolates organism at the species level. Then, susceptibility of isolates to different antibiotics was assessed using disc diffusion method and broth micro dilutions to determine the minimum inhibitory concentrations (MICs). Pulsed field gel electrophoresis (PFGE) was used for typing of isolates. Results: Totally, 10 CRAB infections were isolated during the 6 months study period, and all of them were positive for blaOXA-51-like gene in PCR assay. They were resistant to all tested antibiotics, except colistin, polymyxin B, and tigecycline. CRAB isolates had a high MIC values for imipenem, cefotaxime, and amikacin at NICU. Based on the results of PFGE, 3 pulsotypes including clone A (7%), clone B (2%), and clone D (1%) were seen in the 10 CRAB isolates. Clone A was a dominant clone and spread in different wards of the hospital, especially in other ICUs and the emergency ward. Conclusion: Based on the results of this study, CRAB infection, with a high resistance rate, has the ability to enter into important wards such as NICU, and thus it is highly important to control the presence of these isolates in different parts of the hospital. Moreover, the similarity between the pulsotypes showed the ability of transferring CRAB infection from different wards of the hospital to the NICU.