Detection of the most prevalent antibiotic resistance genes in Acinetobacter baumannii strains isolated from hospital infections and determination of their antibiotic resistance pattern

Acinetobacter baumannii is a gram-negative coccobacill that has a great distribution in the nature and is considered as one of the important causes of hospital infections. Due to the antibiotic resistances in this bacterium several problems in the successful treatment of patients and subsequently their mortality have been occurred. The present study was carried out in order to detect the most prevalent antibiotic resistance genes in Acinetobacter baumannii strains isolated from the hospital infections. This descriptive study was carried out on 121 strains of Acinetobacter baumannii isolated from clinical samples of two hospitals of Tehran city. After identifying isolates using the biochemical tests, the antibiotic resistance pattern of them was done using the disk diffusion and molecular (in order to identify the antibiotic resistance genes) methods. Of 121 strains of Acinetobacter baumannii isolated from infectious samples, the most commonly detected antibiotic resistance was against tetracycline and the most sensitivity was achieved against chloramphenicol, nitrofurantoin and meropenem by distribution of 1.65 %. The distribution of dfrA1, tet(A), aac(3)-IV, sul1, tet(B), aadA1, qnr, CITM, blaSHV, sim, vim, oxa-58-like. Oxa-24-like, imp, oxa-51-like, oxa-23-like, cat1 and cmlA were 79 (65.27 %), 71 (58.67 %), 68 (56.19 %), 67 (55.37 %), 44 (36.36 %), 41 (33.88 %), 29 (23.96 %), 28 (23.14%), 24 (19.83 %), 17 (14.04 %), 16 (13.22 %), 14 (11.57 %), 12 (9.91 %), 10 (8.26 %), 9 (7.43 %), 8 (6.61 %), 5 (4.13 %) and 3 (2.47 %), respectively.Discussion and Multiple antibiotic resistance in studied isolates the use of molecular techniques in the antibiogram test to select the most effective antibiotic treatment of infections and the importance of continued antibiotic surveillance that will provide succession in the efforts of infection control programs for the future.