Prevalence of resistance to colistin, tigecycline and minocycline in Acinetobacter baumannii isolated from clinical samples in 2014

Background: Colonization rate of Acinetobacter baumannii is increasing in hospitalized patients especially in long term hospitalized one and / or who were treat with extended spectrum antibiotics or anticancer. Antibiotic resistance in A. baumannii is considerable because more prevalence of them cause nosocomial infections and can impose high cost to health systems and patients. The aim of this study was determination of tigecycline, minocycline and colistin resistance A. baumannii in selected center in Tehran, Iran. Materials and Methods: This study was descriptive and functional foundation. In this study A. baumannii were collected from Milad, Mofid, Taleghani, Motahari and Loghman hospital, Tehran and transferred to laboratory of pediatric infections research center. Collected bacteria were identified by conventional microbiology tests. Antibiotic susceptibility testing was determined according to CLSI guide line. Tigecycline, minocycline and colistin resistance strains were isolated.  Results: In this study, 105 A. baumannii were collected from five selected hospitals: 48 (46%) from Milad, 33 (31%) from Motahari, 17 (16%) from Loghman, 4 (4%) from Mofid and 3 (3%) from Taleghani hospital. The highest resistance was observed against cefepime and high frequency of carbapenem and minocycline was observed. On the other hand, observed resistance to aminoglycosides was 93% at least. Tigecycline is the most effective antibiotic after colistin. Colistin resistant confirmed just in one isolate by E. test. Conclusion: The results of this study indicated that high rate of antibiotic resistance in A. baumannii even resistant to third and fourth generation of cephalosporin and carbapenem antibiotics. The treatment of MDR strains of A. baumannii become more complicated if the spread of them were not been controlled