## 3 Results
### Multidrug Resistance and esp/asa1 Gene Prevalence among Enterococcus spp. Isolates  
Among 110 clinical isolates tested, we found 63 (57%) _Enterococcus_ spp. strains (_E. faecalis_, 53% and _E. faccium_, 100%) resistant to at least two groups of antibiotics using the disk diffusion method. The highest number of _Enterococcus_ spp. isolates were in the high-level aminoglycos-resistance group (_HLAR_) and, at the same time, exhibited resistance to penicillas (ampicillin) and quinolones (ciprofloxacin), which correlates with molecular-genetic analysis. Multidrug resistance was detected in 43 (39%) of the isolates (_E. faecalis_, 32% and _E. faccium_, 100%) (Table 6). Various resistance patterns were observed, of which _A-CP-G (HLAR)_ (ampicillin-ciprofloxacin-high-level gentamicin) was more common (79%). The largest number of isolates that possessed this particular antimicrobial resistance pattern harbored the quorum-sensing regulation _asa1_ (_n_ = 21, 81%) and _esp_ (_n_ = 5, 19%) genes. Four (33%) of the _E. faccium_ (a single isolate from urine and three isolates from haemocultures) exhibited vancomycin resistance. Statistical difference was not established between MDR _E. faecalis_ and _E. faccium_ isolates and the same species resistant to one or two antibiotic groups (_p_ = 0.606) (Table 7). However, a statistically significant difference was found between enterococcal isolates positive for the _asa1_ or _esp_ gene or both the _asa1_ and _esp_ genes and those that possessed the antimicrobial \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Antimicrobial Resistance Genes** & _E. faecalis_ & _E. faccium_ & **Total** \\  & **(_n_)** & **(_n_)** & **_n_ (\%)** \\ \hline _VanB_ & 0 & 0 & 0 (0\%) \\ \hline _VanA_ & 1 & 0 & 1 (1\%) \\ \hline _emeA_ & 1 & 0 & 1 (1\%) \\ \hline _anc(\(\theta^{\prime}\))/aph(2\(\arcsec\)) + emeA_ & 80 & 6 & 86 (78\%) \\ \hline _aac(\(\theta^{\prime}\))/aph(2\(\arcsec\)) + emeA_ + VanA_ & 11 & 3 & 14 (13\%) \\ \hline _aac(\(\theta^{\prime}\))/aph(2\(\arcsec\)) + emeA_ + TEM_ & 2 & 1 & 3 (3\%) \\ \hline _aac(\(\theta^{\prime}\))/aph(2\(\arcsec\)) + emeA_ + VanA_ + TEM_ & 2 & 1 & 3 (3\%) \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Prevalence and distribution of antimicrobial resistance genes among MDR _Enterococcus_ spp. clinical isolates. \begin{table}
\begin{tabular}{c c c c} \hline \hline \multirow{2}{*}{_Enterococcus spp._} & \multicolumn{3}{c}{**Quorum-Sensing Regulation Genes**} \\ \cline{2-4}  & _asa1_ & _esp_ & _asa1 + esp_ \\ \hline _E. faecalis_ & & & \\ _(_n_) & 86 & 8 & 4 \\ _E. faccium_ & & & \\ _(_n_) & 8 & 3 & 0 \\ \hline Total & 94 (85\%) & 11 (10\%) & 4 (4\%) \\ \hline Chi-square Observed value/Critical value & 3367/3841 & 1930/3841 & \\ \hline _p_-value 1 & 0.067 & 0.165 & \\ \hline \hline \end{tabular} \({}^{\dagger}\)_E. faecalis_ vs _E. faccium_, _p_-value < 0.05 was considered statistically significant.  
\end{table} 
Table 5: Distribution of _asa1_ and _esp_ genes among _Enterococcus_ spp. clinical isolates. = 34, _E.ecium_, \(n\) = 2 respectively). Previous reports from Iran and Saudi Arabia have also indicated the prevalence of urinary tract infections, followed by wound infections [24, 25, 26]. These data support the statement that isolation rate variation depends on the geographical area and the type of clinical samples in the particular study. The present study revealed a higher incidence of the quorum-sensing regulation genes (_asa1_ and _esp_) encoding the virulence factors involved in biofilm formation. The _esp_ gene was more frequently found in _E. facecium_ (27\(\%\)) than in _E. faecalis_ isolates (12\(\%\)), which confirms the findings of authors from Italy and Iran (72\(\%\)/60\(\%\) and 66\(\%\)/47\(\%\), respectively) [27, 28]. However, in some studies, the _esp_ gene was more prevalent among _E. faecalis_[29, 30] or was not found in _E. facecium_ at all [31, 32].