Аntibiotic and serum resistance of Enterobacteriaceae strains isolated from outpatients with infections of urogenital tract

Abstract

The present study is focused on the antibiotic and serum resistance of Enterobacteriaceae strains associated with community infections of the urogenital tract. During a one-year period from April 2016 to March 2017 total of 318 Enterobacteriaceae strains were collected from urine samples, vaginal and urethral secrets and ejaculates of outpatients with urinary and genital tract infections at IMDL “Chronolab” - Plovdiv, Bulgaria. The most common etiological agent was Escherichia coli (64.8%), followed by Klebsiella spp. (17%) and Proteus mirabilis (10.37%). The antibiotic susceptibility tests showed high resistance against ampicillin (49%), mecillinam (71%), doxycycline (41%) and high susceptibility to cephalosporins (cefuroxime 84.6%; cefoxitin 83.7%; cefotaxime 91.5%; cefepime 87.7%) and fluoroquinolones (ciprofloxacin 85%, norfloxacin 79%, levofloxacin 83%;). Significant resistance was established to nitrofurantoin (24%). Amongst the tested strains, 8.5% produced extended spectrum beta-lactamases (ESBLs). We tested serum susceptibility of strains and found that 84% of trains were resistant to the bactericidal activity of the normal human serum. Our data suggest that most likely the resistance to complement is one of the mandatory virulence factors for the majority of the Enterobacteriaceae strains associated with urogenital infections. The susceptibility profile of the tested Enterobacteriaceae strains confirms the need for constant data update on the antibiotic resistance and patterns of virulence of etiological agents of the urogenital infections.