Early Detection of A Possible Multidrug-Resistant Acinetobacter Baumannii Outbreak in the Local Hospital Setting By Using Random Amplified Polymorphism Dna-Polymerase Chain Reaction (Rapd-Pcr), Oxacillinase Gene Profiles, and Antibiograms

Background and objectives: detecting the source of a potential outbreak of multidrug resistant (mdr) acinetobacter baumannii is necessary to be investigated. this study aimed to detect the possibility of a. baumannii outbreak in a hospital setting using a combination of random amplified polymorphism dna- polymerase chain reaction (rapd-pcr), antibiograms, and the presence of oxacillinase genes.materials and methods: the antibiogram of 31 clinical isolates and six environmental isolates of a. baumannii were determined by vitek® 2 compact. oxacillinase genes (oxa-23, -24, -51, and -58) were detected by pcr, and rapd-pcr was conducted using daf-4 and eric-2 primers. the similarity index and dendrogram were generated using gelj v2.3 software.results: the antibiograms showed that all mdr a. baumannii isolates has very limited susceptibility to cephalosporins, but mostly susceptible to tigecycline. all isolates were positive for blaoxa-51-like gene, thirty-two of 37 total isolates (86.5%) were positive for blaoxa-23-like gene, and none were positive for blaoxa-24-like and blaoxa-58-like genes. rapd-pcr showed that the daf-4 primer on average had more band visualization and lower similarity index’s variation compared to the eric-2. the discriminatory power of daf-4 was 0.906. there was a significant correlation between the daf-4 dendrogram pattern with the antibiogram (r=0.494, p<0.001) and the presence of blaoxa-23-like gene (r=0.634, p<0.001) from all icu a isolates. six out of fourteen icu a isolates belonged to the same cluster with >95% similarity index, while one clinical isolate having an identical dendrogram and antibiogram pattern with an environmental isolate within this cluster.conclusion: there is a high probability of mdr a. baumannii outbreak within icu a detected by multiple analysis of rapd-pcr, antibiogram and the blaoxa-23-like gene profiles. this combinatorial approach is conceivable to mitigate possible outbreak situations of a. baumannii in the local hospital without sophisticated microbiology laboratory.