Oxacillinase Gene Distribution, Antibiotic Resistance, and Their Correlation with Biofilm Formation in Bloodstream Isolates.

The limitations of treatment options in bloodstream infections caused by multidrug-resistant (MDRAB) have been related to high morbidity and mortality. The aim of our present study was to determine antimicrobial susceptibility profiles, molecular resistance patterns, and biofilm properties of isolated from bloodstream infections. In the present study, a total of 44 bloodstream isolates were included. Antimicrobial susceptibility profiles and biofilm formation ability were assessed. The distribution of class D carbapenemases, IS, IS/OXA-23, NDM-1, , and was investigated by polymerase chain reaction (PCR). Arbitrarily primed-PCR (AP-PCR) was performed to evaluate clonal relationships. A total of 32 isolates were MDRAB, whereas 6 isolates were also resistant to colistin without positivity. All isolates were harboring OXA-51 gene, whereas OXA-23 positivity was 63.6%. Fifty percent of the isolates had IS IS upstream of OXA-23 was determined in 18 isolates. None of the isolates were positive for NDM-1 gene. Majority of the strains were strong biofilm producers (86.8%). A total of 56.8% of the isolates were positive for gene with no direct association with strong biofilm formation. However, OXA-51 + 23 genotype and trimethoprim-sulfamethoxazole resistance showed a significant relationship with biofilm formation. AP-PCR analysis revealed six distinct clusters of . Herein, majority of the blood isolates were characterized as OXA-51+OXA-23 carbapenemase genotype and were strong biofilm formers. None of the isolates were positive for NDM-1, which was promising. Resistant isolates were tended to form strong biofilms. Our results highlight the emergence of oxacillinase-producing MDRAB isolated from bloodstream with high biofilm formation ability.