Prevalence of extended spectrum beta-lactamase (ESBL) Escherichia coli recovered from ICU and non-ICU

. Research conducted at Zainoel Abidin General Hospital in Banda Aceh between January 2022 and July 2023, focused on the prevalence and susceptibility patterns of extended-spectrum beta-lactamases (ESBL)- producing Escherichia coli associated with nosocomial infections. This study employed a retrospective descriptive methodology to analyze clinical specimens from both the intensive care unit (ICU) and non-ICU settings. Of the 520 isolates examined, 365 (70.19%) were identified as ESBL-producing Escherichia coli . The age group of 56-65 had the highest prevalence (28.21%), with female patients contributing 52.50% of the isolates. Both ESBL-producing and non-ESBL-producing E. coli had almost equivalent prevalence among patients treated in the ICU and non-ICU, accounting for 67%. Antibiotic susceptibility testing revealed high levels of resistance to carbapenem. Conversely, polymyxin B showed complete susceptibility (100%) and cefoxitin exhibited an 85% susceptibility rate. These findings underscore the alarm resistance levels of ESBL-producing Escherichia coli isolates.


Introduction
Escherichia coli strains harboring Extended-Spectrum Beta-Lactamases (ESBLs) have garnered considerable recognition due to their substantial role as pathogenic agents, contributing significantly to the incidence of infections across global healthcare settings and the general populace.Notably, the distribution of ESBL-encoding E. coli displays geographical variability, as substantiated by multiple research investigations conducted in various nations.Extensive evidence points to the identification of ESBL-producing E. coli in diverse contexts within the Indonesian settings, encompassing healthcare facilities [1], dairy farming establishments [1][2][3], and the surrounding ecological milieu [1].These discerned occurrences emphasize the potential for interspecies transmission of ESBL-producing E. coli, thereby warranting heightened attention and investigation [1].
Within the healthcare environment, ESBL E. coli has been frequently observed in close association with urinary tract infections (UTIs), as substantiated by antecedent research investigations [4][5][6][7][8][9][10].Moreover, distinct studies have elucidated its connection with bacteriuria [11], while others have discerned its implication in various categories of infectious ailments [12].It is important to note that the occurrence of infections associated with ESBL E. coli is markedly impacted by recent hospital admissions and the prior utilization of antibiotics [13].
The development and dissemination of ESBLs are predominantly reported in the Enterobacteriaceae family, with a specific emphasis on Klebsiella pneumoniae, K. oxytoca, and E. coli [5].The prevalence of ESBL-producing E. coli exhibits notable variation across numerous scientific investigations and ecological settings.Furthermore, introducing and disseminating ESBL-producing E. coli provides substantial obstacles in infection control and therapeutic interventions.These isolates frequently to resist many categories of antibiotics, which restricts the range of available treatment choices [14].Moreover, infections related to ESBL-producing E. coli are linked to longer hospitalization periods, higher healthcare expenditures, and greater fatality rates than infections caused by non-ESBL-producing E. coli [15].Hence, the implementation of efficient surveillance and infection control strategies is of utmost importance in mitigating the widespread of ESBL-producing E. coli in healthcare facilities and broader communities.
The primary objective of this investigation was to assess the prevalence of both ESBLproducing and non-ESBL-producing strains of E. coli within clinical specimens obtained from patients undergoing treatment in the Intensive Care Unit (ICU) and non-ICU wards, at Zainoel Abidin General Hospital.

Material and Methods
The clinical specimens utilized in this research investigation were obtained from patients admitted and discharged from Zainoel Abidin General Hospital in Banda Aceh, Indonesia, between January 2022 and July 2023.The specimens gathered comprised an assortment of sample categories, such as swabs, blood, urine, sputum, and other bodily fluids.To verify the accuracy of the data, each sample was subjected to a thorough review, and all essential details like sample type, collection time, and patient gender were documented.Faculty of Medicine, Universitas Syiah Kuala, granted ethical approval for this study.
The processing of clinical samples involved their inoculation onto blood and MacConkey agar (Merck, Germany) plates.Blood specimens underwent a preliminary culturing step using BacT/ALERT ® 3D following the manufacturer's protocols before inoculation onto agar plates.These agar plates were then subjected to an incubation period at 37°C lasting 24 hours, subsequently undergoing Gram staining and macroscopic as well as microscopic examination under 1000x magnification for morphological characterization.
The identification of bacterial species and their susceptibility to antimicrobial agents was performed using the VITEK ® 2 Compact system (Biomeriux, Lyon, France).Isolates of pure bacterial colonies retrieved from clinical samples were suspended in 0.45% NaCl, adjusted to match the turbidity of a 1.8-2.2McFarland Standard solution, and subsequently introduced into appropriate cassettes tailored for both identification and antimicrobial susceptibility assessment.Antimicrobial susceptibility testing adhered to the guidelines delineated by the Clinical and Laboratory Standards Institute (CLSI) and encompassed an array of antibiotics.
The distribution of E. coli isolates across different species was subjected to descriptive analysis, considering variables such as the clinical sample type, the gender and age of the associated patients, and the wards.Data were organized using Microsoft Excel to generate informative tables and charts for descriptive representation.For statistical analyses, the chi-

Results and Discussion
During the investigation, 520 E. coli isolates were recovered from clinical specimens.Among them, 70.18% (n=365) were identified as producers of ESBLs with the patients's profiles are tabulated in Table 1.The high prevalence of ESBL E.coli in the present research aligns with a prior study, which reported a prevalence of ESBL E. coli accounting for 51.6% of the total clinical E. coli isolates (n=455) obtained from healthcare facilities in northeast Iran [16].In this current research, the predominant source of ESBL-E.coli isolates was urine, comprising 145 isolates (71.42%) out of 203 from infected urine cultures, followed by pus and blood, accounting for 118 (32.32%) and 56 isolates (15.34%), respectively (Figure 1).This underscores the significance of ESBL E. coli as the primary causative agent in urinary tract infections (UTIs).Multiple studies have established the association of ESBL E. coli with both community-and hospital-acquired UTIs [17][18][19].In community settings, ESBL-producing E. coli has emerged as a notable etiological factor for UTIs [19].A study conducted in China revealed a high prevalence of ESBL-producing E. coli among adults afflicted with community-acquired UTIs [17].In hospital environments, ESBL E. coli has been linked to hospital-acquired infections [18].Notably, a study conducted in Saudi Arabia also reported a substantial prevalence of ESBL-producing E. coli in both communities-and hospital-acquired UTIs [4].Regarding patient age groups, as depicted in Figure 2, the highest occurrence of ESBL E. coli was observed among senior patients, specifically in the 56-65 age group, comprising 103 isolates (28.21%), and the 46-55 age group, consisting of 100 isolates (27.39%).Notably, this distribution pattern revealed that the highest prevalence of ESBL-producing E. coli was observed within patients aged 46-56 years [20].In line with our findings, this study documented a prevalence of 33.3% for ESBL-producing E. coli among clinical uropathogenic isolates in Riyadh, Saudi Arabia.Furthermore, other research endeavors have identified age as an independent risk factor associated with mortality in patients afflicted with ESBL E. coli bacteremia [21].These observations imply that age may influence the distribution and the clinical outcomes of infections caused by ESBL E. coli.
In the present study, both ESBL and non-ESBL E. coli displayed nearly equivalent prevalence rates among patients receiving treatment in both the Intensive Care Unit (ICU) and non-ICU settings, constituting 67% of the total cases, as indicated in Figure 3.Although the prevalence of extended-spectrum beta-lactamase (ESBL)-producing E. coli is notably higher within Intensive Care Units (ICUs), it is important to acknowledge that non-ICU patients are also exposed to significant risks of colonization or infection, especially individuals residing in long-term care facilities (LTCFs) or those with a history of recurrent hospitalizations [8,22,23].These non-ICU patients may exhibit similar risk factors as their ICU counterparts, including prolonged hospital stays and extensive antibiotic exposure [8,22,23].In LTCFs, the proximity of patients and frequent utilization of antibiotics can contribute to the dissemination and selection of ESBL-producing strains [23,24].Additionally, recurrent hospitalization can heighten the susceptibility to ESBL-producing E. coli colonization or infection [25].Concerning the gender distribution of patients, the prevalence of infections attributed to both ESBL and non-ESBL E. coli was notably more pronounced among females, constituting 188 isolates (52.50%), compared to 177 isolates (48.49%) in males, as illustrated in Figure 4.This observation aligns with prior research findings that consistently highlight a heightened incidence of ESBL E. coli infections in females compared to their male counterparts.For instance, a study conducted in Saudi Arabia revealed that females exhibited an elevated susceptibility to urinary tract infections caused by E. coli strains displaying resistance to various antibiotics, including ESBLs, compared to males [4].Similarly, a research study conducted in Iran reported a substantially higher incidence rate of ESBL E. coli isolates in females, reaching 81.8%, in contrast to a mere 18.2% in males [5].This gender-based trend was further corroborated by a subsequent investigation in India [26].However, it is worth noting that there have been instances where studies have indicated a more pronounced prevalence of ESBL E. coli infections in males than females [11].The results of antibiotic susceptibility testing revealed that ESBL E. coli displayed resistance to amikacin, ceftadine, colistin, and cefoperazone/sulbactam, as outlined in Table 2.These findings are align with prior research, which has consistently reported resistance of amikacin, ceftazidime, colistin, and cefoperazone/sulbactam against ESBL E. coli isolates, as determined through antibiotic susceptibility testing [27].The emergence of resistance to amikacin in ESBL E. coli is a matter of concern, given the widespread utilization of this antibiotic in managing infections stemming from multidrug-resistant Gram-negative bacteria [28].It is worth noting the challenges posed by the development of resistance to ceftazidime and cefoperazone/sulbactam, as these antibiotics are frequently employed as empirical treatment choices for infections caused by ESBL bacteria [29].Resistance to colistin is particularly alarming, as this antibiotic is regarded as a last-resort therapy for multidrugresistant Gram-negative infections [27].
This study showed that ESBL and non-ESBL E. coli strains exhibited substantial resistance to ceftriaxone, cefotaxime, doxycycline, and levofloxacin.This observation is consistent with the prevalent occurrence of antibiotic resistance previously documented in E. coli isolates [30][31][32][33].The observed heightened resistance levels to ceftriaxone and cefotaxime can be attributed to the widespread distribution of ESBL E. coli strains across various settings, including hospitals, communities, and the environment [30,31,34].The increasing prevalence of resistance to doxycycline and levofloxacin is concerning, given their frequent use in managing urinary tract infections and other community-acquired diseases [32,35].
In contrast, the isolates in the current study showed notable susceptibility to doripenem, imipenem, meropenem, and polymyxin B. Previous studies have demonstrated favorable susceptibility outcomes of these antibiotics against E. coli [27].This is encouraging because of the efficacy of these antibiotics against gram-negative bacteria that are resistant to many drugs, including ESBL Escherichia coli [27].Meticulous monitoring of carbapenems and polymyxins is necessary to mitigate the potential resistance [31].

Fig. 1 .
Fig. 1.The distribution and prevalence percentages (%) of ESBL E. coli (n=365) and non-ESB E. coli (n=155) isolates in relation to clinical specimens during the period spanning from January 2022 to July 2023.The numerical values within each column denote the total count of isolates.Analysis employing the Chi-square test for independence revealed no significant association between the types of clinical specimens and the presence of ESBL in E. coli (P = 0.522; χ² = 3.218).

Fig. 2 .
Fig. 2. The distribution and prevalence percentages (%) of ESBL E. coli (n=365) and non-ESBL E. coli (n=155) isolates categorized by patients' age groups during the timeframe spanning from January 2022 to July 2023.The numerical values provided in each column signify the total count of isolates.Employing the Chi-square test for independence, it was determined that a statistically significant association exists between the types of clinical specimens and the presence of ESBL in E. coli (P = 0.044; χ² = 15.868).

Fig. 3 .
Fig. 3.The distribution and prevalence percentages (%) of ESBL E. coli (n=365) and non-ESBL E. coli (n=155) isolates in relation to patients' wards during the period spanning from January 2022 to July 2023.The numerical values within each column denote the total count of isolates.Analysis employing the Chi-square test for independence revealed that no significant association between the types of patients' wards and the presence of ESBL in E. coli (P = 0.273; χ 2 =1.203).

,Fig. 4 .
Fig. 4. The distribution and prevalence percentages (%) of ESBL E. coli (n=365) and non-ESBL E. coli (n=155) isolates in relation to patient's gender during the period spanning from January 2022 to July 2023.The numerical values within each column denote the total count of isolates.Analysis employing the Chi-square test for independence revealed no significant association between the patient's gender and the presence of ESBL in E. coli (P = 0.875; χ 2 =0.025).

Table 1 .
The patients' profiles (ages and genders) of ESBL and non-ESBL E. coli obtained from clinical specimens during the period of January 2022 to July 2023

Table 2 .
The antibiotic susceptibility profiles of ESBL E. coli (n=365) and non-ESBL E. coli (n=155) isolates obtained from clinical specimens during the period of January 2022 to July 2023 E. coli were predominantly observed in urine and pus specimens, particularly among senior patients aged 46-56 years.Furthermore, these isolates exhibited a higher prevalence among female patients receiving treatment in both ICU and non-ICU settings.The antibiotic susceptibility profile of ESBL E. coli isolates underscores the critical need for judicious antibiotic usage and the enforcement of stringent infection control to mitigate the emergence of multidrug-resistant bacterial strains.Subsequent research endeavors should aim to elucidate the mechanisms underpinning resistance and develop innovative therapeutic strategies for addressing ESBL-producing E. coli infections a Chi-square calculated for comparison of susceptibility in ESBL-producing E. coli and non-ESBLproducing E. coli.bPvalues generated from the chi-square4 ConclusionESBL