Çok İlaca Dirençli İnvaziv Acinetobacter Baumannii İzolatlarında Biyofilm Yapımının Değerlendirilmesi

Abstract

Multidrug resistant Acinetobacter baumannii isolates lead to epidemics and loss of patients in the hospital setting. In addition to diverse resistance mechanisms, some A. baumannii strains have biofilm producing capacity, therefore further decreasing antibiotic effectiveness. The aim of this study was to determine the relationship between multidrug resistance and existence of biofilm and virulence genes among 156 invasive multi-drug resistant Acinetobacter baumannii isolates from 10 medical centers in different geographical regions of Turkey. Isolates with known antibiotic susceptibilities and pulsed-field gel electrophoresis (PFGE) patterns were included in the study. Quantitative microplate biofilm method was used to detect biofilm production. The presence of virulence genes csgA, csuE, fimH, ompA and blaper-1 was investigated by polymerase chain reaction (PCR). Among all isolates, 60.25% (94/156) showed biofilm formation ability. Of the 94 isolates, 17 were weakly, 33 were moderately and 44 were strongly positive. The frequency of genes csgA, csuE, ompA and fimH among the isolated strains (n:156) were 70.51%, 32.05%, 21.79%, 7.05%, respectively. The frequency of virulence genes among biofilm producing isolates were csgA, csuE, ompA and fimH were 41.48%, 20.2%, 24.46% and 5.31%. As a conclusion, this study showed that there is a strong relationship between multidrug resistance and biofilm formation in MDR invasive A. baumannii isolates. As a sign of relationship between biofilm formation and different virulence genes, biofilm producing MDR invasive A. baumannii isolates were found positive for virulence genes but these genes do not seem to be necessary for biofilm formation in MDR invasive isolates of A. baumannii. More detailed studies were needed to verify the exact association of virulence genes with biofilm formation.