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Chlorhexidine and benzalkonium chloride: promising adjuncts in combating multidrug resistant Klebsiella pneumoniae in healthcare settings

BMC Infectious Diseases volume 25, Article number: 670 (2025) Cite this article

Abstract

Background

Hospital-acquired infections caused by multidrug resistant (MDR) Klebsiella pneumoniae pose a significant global health threat. Effective antisepsis and disinfection protocols are mandatory to prevent these infections. This study aimed to isolate Klebsiella pneumoniae, evaluate antimicrobial susceptibility, and assess the efficacy of selected biocides.

Methods

Fifty clinical MDR Klebsiella pneumoniae isolates were collected from various hospital departments. Antimicrobial susceptibility was determined using the disc diffusion method. Minimum inhibitory concentrations (MICs) of chlorhexidine and benzalkonium chloride were measured via agar dilution. Conventional PCR was employed to detect biocide resistance genes (qacE∆1 and cepA).

Results

Klebsiella pneumoniae was identified in 19.16% of cases. All isolates exhibited multidrug resistance, with multiple antimicrobial resistance indices ranging from 0.24 to 0.92, reaching up to 1. Benzalkonium chloride MICs significantly increased with resistance, reaching up to 64 µg/mL, while chlorhexidine MICs were consistent across isolates. The qacE∆1 and cepA genes were detected in 62% and 72% of isolates, respectively, with a significant association between qacE∆1 and cephalosporin resistance. No significant correlation was found between biocide MICs and clinical specimen types or hospital units.

Conclusion

The cepA gene is closely associated with extensive drug resistance in Klebsiella pneumoniae, emphasizing its role in antimicrobial resistance. Optimized biocide formulations, when properly developed and applied, can play a crucial role in combating and preventing infections caused by multidrug-resistant Klebsiella pneumoniae.

Clinical trial number

Not applicable.

Peer Review reports

Introduction

Klebsiella pneumoniae, listed by the World Health Organization as a priority pathogen, is infamous for driving multidrug resistant (MDR) healthcare associated infections. Controlling the spread of K. pneumoniae requires ongoing assessment and advancement of effective antimicrobial strategies, including both antibiotics and biocides [1]. Biocides, including skin antiseptics and surface disinfectants, play a vital role in healthcare settings by reducing microbial bioburden on hospital personnel and within the environment. As prevention is often more effective than treatment, the development and application of biocidal agents with broad-spectrum bactericidal activity remain essential priorities, particularly in combating drug resistant K. pneumoniae [2, 3].

Chlorhexidine (CHX), a widely used biocide, is incorporated into cosmetics and pharmaceutical products such as eye drops, wound dressings, and antiseptic washes. CHX demonstrates activity against Gram-positive and Gram-negative bacteria, facultative anaerobes, aerobes, and yeasts. Its bactericidal action arises from its cationic nature, which enables it to bind to negatively charged bacterial cell walls, causing membrane disruption. At low concentrations, CHX exhibits bacteriostatic effects, while at higher doses, it becomes bactericidal [4]. Similarly, benzalkonium chloride, a member of the quaternary ammonium compounds (QACs), is a cationic surfactant with notable bactericidal and fungicidal properties. QACs are widely used due to their pleasant odor and low toxicity. Their primary mechanism of action involves disrupting the structure and function of cell membranes, with biocidal efficacy varying significantly depending on concentration [5].

Concerns about bacterial resistance to biocides are growing, paralleling the global challenge of antibiotic resistance [6]. The excessive use of antibiotics and biocides has exerted selective pressure on bacterial strains, leading to the widespread distribution of resistance genes. Biocide resistance genes, such as qacA/B, qacE, qacEΔ1, cepA, and arcA, have been identified in multidrug resistant (MDR) bacteria [7].

The cepA gene, which encodes a chlorhexidine efflux pump, is associated with chlorhexidine resistance in Gram-negative bacteria, particularly in Klebsiella spp [1]. Similarly, quaternary ammonium compound (QAC) resistance genes (qac) produce efflux pumps that actively expel biocides from bacterial cells, reducing their intracellular antimicrobial effectiveness [8]. Alarmingly, MDR strains have demonstrated cross-resistance to biocides, likely due to shared resistance mechanisms, further complicating the fight against hospital-acquired bacterial infections [9].

The objective of this study was to explore the relationship between the presence of biocide resistance genes (qacE∆1 and cepA) and the minimal inhibitory concentrations (MICs) of chlorhexidine and quaternary ammonium compounds in MDR Klebsiella pneumoniae with the goal of advancing strategies to control MDR Klebsiella infections.

Patients and methods

Study design and ethical consideration

This study was performed in Medical Microbiology and Immunology Department, Faculty of medicine, Menoufia University during the period from May 2022 to June 2024.Totally two hundred- eighty four clinical samples were collected from hospitalized patients with evident infections 48 h or more after hospital admission. Patients from Intensive care units (ICUs) and different hospital departments were included. Different age groups were involved. Clinical and demographic data were collected and analyzed, considering patients’ age, gender, hospital stay duration, antibiotic uptake, comorbidities, and exposure to invasive procedures. The study protocol was approved by the local Ethics Committee of the Faculty of Medicine, Menoufia University (IRB: 3/2022MICRO44).

Clinical sample collection and transport

Different clinical samples were collected aseptically based on the infection site: wound and burn swabs, respiratory samples (sputum and endotracheal aspirates), mid-stream urine from non-catheterized patients, catheter port urine from catheterized patients, and blood samples into culture bottles (bioMerieux, France). Each sample was carefully labeled and promptly transported to the microbiology laboratory for rapid processing.

Isolation and identification of Klebsiella spp

All clinical samples were inoculated onto conventional media obtained from Oxoid, UK for the isolation and identification of Klebsiella spp., and CLED media for urine bacterial counting, followed by aerobic incubation at 37 °C for 24–48 h. The phenotypic identification of Klebsiella isolates was based on colony morphology and biochemical reactions [10]. Further confirmation and species identification were performed using the VITEK-2 Compact System- Biomerieux, France, where fifty Klebsiella pneumoniae isolates were verified.

Antimicrobial susceptibility testing (AST) of Klebsiella pneumoniae isolates

Antimicrobial susceptibility testing of Klebsiella pneumoniae isolates was performed using the Kirby-Bauer disk diffusion method on Muller-Hinton agar, with results interpreted according to CLSI 2023 guidelines. Various antibiotic discs (Oxoid, UK) were tested as demonstrated later, including ampicillin, carbapenems, cephalosporins, aminoglycosides, tetracyclines, macrolides, fluoroquinolones, trimethoprim-sulfamethoxazole and nitrofurantoin exclusively for urine samples (CLSI, 2023). On the same line, Colistin(Sigma, Egypt). MIC was specifically tested through the agar dilution method considered as critical last-resort antibiotic option against multidrug resistant Klebsiella [11]. The Multiple Antimicrobial Resistance (MAR) index that quantifies the resistance of bacterial isolates to various antimicrobial agents was calculated by dividing the number of antibiotics to which an isolate is resistant by the total number of antibiotics tested [12].

Determination of the minimum inhibitory concentrations (MICs) of biocides

The MICs for benzalkonium chloride and chlorhexidine were determined using the agar dilution method. Benzalkonium chloride (LOBA chemical, India– 50 gm/100 ml solution) was serially diluted in Muller-Hinton agar to achieve a concentration range of 0.125 to 1024 µg/ml. Chlorhexidine HCL (125 mg/100 ml - Hexitol, Egypt) was similarly diluted. Prepared agar plates were incubated at 37 °C, and the MIC was determined as the lowest concentration of biocide at which no visible colony growth of studied Klebsiella isolate was observed [11].

Molecular detection of biocide resistance genes

Conventional polymerase chain reaction (PCR) was employed to detect the presence of biocide resistance genes qacE∆1 and cepA. DNA was extracted using the Thermo Fisher GeneJET purification kit and stored at -20 °C. PCR amplification was performed using T professional Thermocycler (Biometra, Germany) with specific primers for qacE∆1 and cepA resistance genes. The optimized PCR protocol is illustrated in Table 1. The amplified products were analyzed by electrophoresis on a 1.5% agarose gel, run at 100 volts for one hour. Gene presence was confirmed by visualization under a UV trans-illuminator, with bands appearing at 190 bp for qacE∆1and 1051 bp for cepA [13, 14].

Table 1 Primer sequences and thermal cycling conditions of QacE∆1 and CepA resistance genes
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Statistical analysis

Data coding, validation and analysis were conducted by the Statistical Package for the Social Sciences (SPSS), version 20 (SPSS Inc., Chicago, IL, USA). Continuous variables are expressed as mean, median, ranges and SD. Categorical variables are expressed as frequencies and percentages. Chi square, ANOVA and Kruskal wallis tests were used. A significance level of P < 0.05 was used in all tests.

Results

Among 261 growing microbial isolates, fifty Klebsiella pneumoniae strains (19.16%) were identified added to other pathogens such as Pseudomonas spp., Staphylococcus aureus and Acinetobacter spp. (Supplementary Tables 1-S). The study population comprised 144 males (55.2%) and 117 females (44.8%), with a mean age of 40.59 ± 22.66 years. Remarkably, 86.3% of the patients had prior antibiotic exposure, and 79% experienced hospital stays lasting seven days or more. Additionally, 74% underwent invasive procedures, highlighting the intensive nature of medical interventions. Comorbidities were present in 68% of cases, reflecting significant underlying health challenges that likely contributed to extended hospitalizations.

Urine samples were the most common source of Klebsiella pneumoniae (38%), followed by blood samples (18%), sputum specimens (14%), burn swabs and wound specimens (12% and 14%, respectively), while tracheal aspirates contributed only 4% of Klebsiella isolates (Fig. 1-a). Intensive care units recorded the highest number of isolates by 42%, followed by surgery department (12%) and burn unit (10%). Each of internal medicine department, chest department and NICU accounted for 8% of isolates, while both of urology department and pediatrics department contributed for 6% each (Fig. 1-b).

Resistance patterns among Klebsiella isolates revealed significant variability. High resistance rates were observed for ampicillin (84%) and tested cephalosporins (≥ 82%). Resistance was similarly high for macrolides (azithromycin, 90%) and quinolones (ciprofloxacin, 78%; levofloxacin, 76%). Surprisingly, newer combinations like ceftazidime-avibactam and piperacillin-tazobactam also showed resistance rates of 70% and 68%, respectively. Conversely, carbapenems demonstrated notable effectiveness, with meropenem showing 80% susceptibility, followed by imipenem (70%) and ertapenem (62%). For urinary isolates, nitrofurantoin exhibited a moderate resistance rate (47.3%). Regarding colistin, most isolates (88%) were intermediate-sensitive (MIC ≤ 2 µg/mL), with only 12% classified as resistant (MIC ≥ 4 µg/mL) following CLSI 2023 guidelines [11] (Supplementary Tables 2-S).

Twenty four Klebsiella isolates (48%) exhibited multidrug resistance (MDR) with MAR indices ranging from 0.24 to 0.71. Extensively drug resistance (XDR) was observed in 40% of isolates (MAR indices: 0.75–0.92), while pan-drug resistance (PDR) with one whole MAR index was noted in 12% of Klebsiella isolates with observed resistance to all tested antibiotics, including colistin (Supplementary Tables 3-S & 4-S).

For biocides, benzalkonium chloride MIC values ranged from 8 to 256 µg/mL, with MIC50 at 16 µg/mL and MIC90 at 64 µg/mL. Chlorhexidine MIC values ranged from 4 to 128 µg/mL, with MIC50 and MIC90 at 64 µg/mL and 128 µg/mL, respectively (Fig. 2-a & 2-b). MDR and XDR strains displayed consistent median MIC values (16 µg/mL) for benzalkonium chloride, whereas PDR strains required significantly higher concentrations (64 µg/mL). This difference was statistically significant (p = 0.005). In contrast, chlorhexidine MIC values did not vary significantly across different resistance phenotypes (p = 0.670) (Table 2).

The qacE∆1 gene was detected in 62% of isolates, compared to 72% for cepA. Co-expression of both genes occurred in 46% of isolates, while 12% Klebsiella strains lacked both genes (Fig. 3). Focusing on the relation between various minimal inhibitory concentrations of Benzalkonium chloride and Chlorhexidine with the presence of qacE∆1 and cepA genes, no significant correlations were seen as demonstrated in Table 3.

Data in Table 4 show in-details the antimicrobial resistance patterns of studied 50 Klebsiella strains in relation to the presence of the cepA and qacE∆1 genes revealing that Cefotaxime and Cefoperazone exhibited significant differences (p < 0.05) in resistance between qacEΔ1-positive and qacEΔ1-negative isolates. However, cepA presence did not show statistically significant resistance differences across tested antibiotics.

Among qacE∆1-positive isolates, 45.1% were multidrug resistant (MDR), 41.9% were extensively drug-resistant (XDR), and 13% were pan-drug resistant (PDR). In comparison, qacE∆1-negative isolates demonstrated 52.6% MDR, 36.9% XDR, and 10.5% PDR, with no significant difference in resistance profiles (p = 0.874). For cepA-positive isolates, 36.1% were MDR, 50% were XDR, and 13.9% were PDR. Conversely, cepA-negative isolates exhibited a higher MDR rate (78.6%) but lower rates of XDR (14.3%) and PDR (7.1%) with observed statistical significance (p = 0.0249).

Among isolates co-expressing both qacE∆1 and cepA genes, 39.1% were MDR, 47.8% were XDR, and 13.0% were PDR. In comparison, isolates lacking both genes exhibited 33.3% for MDR, 50.0% for XDR, and 16.7% for PDR. Chi-square analysis showed no statistically significant association between gene co-expression or absence and resistance phenotypes, with p values of 0.486 and 0.860, respectively. Although qacE∆1 and cepA individually influenced specific resistance patterns, their co-expression or absence did not have a significant impact on the overall resistance profiles of Klebsiella pneumoniae isolates as illustrated in Table 5.

Fig. 1
figure 1

Distribution of Klebsiella pneumoniae Isolates Across Specimens and Departments. (A): Specimen-wise Distribution of klebsiella pneumoniae isolates. (B): Department-wise Distribution of klebsiella pneumoniae isolates

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Fig. 2
figure 2

Benzalkonium Chloride & Chlorhexidine Minimal Inhibitory Concentrations (MIC) Distribution Among Klebsiella pneumoniae Isolates. (A): Benzalkonium Chloride MIC Distribution among isolates. (B): Chlorhexidine MIC Distribution among isolates

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Table 2 Correlation of minimal inhibitory concentrations (MIC) values of Benzalkonium chloride and chlorhexidine with resistance profiles (MDR, XDR, PDR) in Klebsiella pneumoniae isolates (N = 50)
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Fig. 3
figure 3

Agarose Gel Electrophoresis of PCR products for qacE∆1 and cepA Genes. Agarose Gel Electrophoresis Showing PCR Bands for qacE∆1 and cepA Genes. Lane M: DNA Molecular Size Marker (100 − 10,000 bp). (A): Agarose Gel Electrophoresis for qacE∆1 gene. Lanes 2, 4–10, and 12–15: Positive for qacE∆1 with a band size of 190 bp. Lanes 1, 3, and 11: Negative for qacE∆1. (B): Agarose Gel Electrophoresis for cepA gene. Lanes 1–6 and 9–14: Positive for cepA with a band size of 1050 bp. Lanes 7, 8, and 15: Negative for cepA

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Table 3 Association between the minimal inhibitory concentrations (MIC) of Benzalkonium chloride and chlorhexidine with the presence of biocide resistance genes QacE∆1 and CepA in Klebsiella pneumoniae isolates
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Table 4 Correlation of antibiotic resistance patterns in Klebsiella pneumoniae isolates with QacE∆1 and CepA genes
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Table 5 Distribution of QacE∆1 and CepA genes among Klebsiella pneumoniae isolates and their association with different resistance phenotypes
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Discussion

Klebsiella pneumoniae is a common opportunistic pathogen resistant to most antibiotics. The rise of disinfectant resistance further threatens health by reducing biocide effectiveness. Disinfection practices and antibiotic use vary by region, leading to different resistance mechanisms. Local epidemiological studies are decisive for effective infection control, yet such studies are limited in our area [7].

In this study, Klebsiella pneumoniae accounted for 19.6% of detected pathogens, emerging as the most frequently isolated microbe. Notably, higher isolation rates (24.5%) were reported by Mohamed et al. [15]. Also the study of El-Sherbiny, 2024 [16] detected Klebsiella pneumonia by 30.85%. Globally, Antonelli et al. [17] identified Gram-negative bacilli as the predominant group in Italy, with Klebsiella pneumoniae comprising 10.4% of isolates. Similarly, Mobarak-Qamsari and colleagues reported Klebsiella pneumoniae as the leading Gram-negative pathogen among ICU patients in Tehran, accounting for 41.5% of cases [18].

The findings of the current study revealed high resistance rates of Klebsiella pneumoniae to older antibiotics, including ampicillin, cephalosporins, macrolides, quinolones, aminoglycosides, and monobactams, with resistance exceeding 80%. While piperacillin-tazobactam and ceftazidime-avibactam showed about 70% resistance. However, carbapenems remained effective, with susceptibility rates exceeding 70%. These results were consistent with multiple global and regional studies [7, 16, 19, 20]. Conversely, Itani et al. [21] and Worku et al. [22] reported significantly lower resistance rates for these antibiotics, suggesting a lower resistance justified by variability of resistance patterns across regions reflecting the importance of local surveillance data.

This work revealed relatively low resistance to colistin among Klebsiella pneumoniae isolates, with only 6 isolates (12%) classified as resistant, while the majority (44 isolates, 88%) were intermediate-sensitive. These findings were aligned with the low resistance rates reported by Itani et al. [21] in Lebanon (7.7%) and Ibrahim [23] in Saudi Arabia (16.3%). Similarly, Rabie & Abdallah [24] from Egypt reported a resistance rate of 17.2%. In contrast, higher resistance rates were observed in other studies, including Jalal et al. [25] with 21.5% and Abozahra et al. [26] with 39%, highlighting regional and environmental variations in resistance trends.

In the current study, nearly half (48%) of the isolates were classified as MDR, while 40% exhibited XDR, and 12% showed PDR. Similarly, Ahmed et al. [27] in Egypt and Ogefere & Idoko [28] in Nigeria reported MDR prevalence of about 50%. In Iran, Esfahanian et al. [29] observed a lower MDR prevalence of 35% and an XDR rate of 22%, though PDR was not reported. Meanwhile, Itani et al. [21] reported that 61% of Klebsiella pneumoniae isolates were MDR, 7.3% were XDR, while 0.5% were PDR.

Our findings revealed that Klebsiella isolates exhibited multiple antibiotic resistance (MAR) index values ranging from 0.24 to 1.0, reflecting a broad spectrum of resistance levels as described by Ahmed et al. [27]. These patterns were aligned with several global observations. Ayandele et al. [30] reported MAR indices ranging from 0.29 to 1.0 among Klebsiella pneumoniae isolates from clinical settings in Nigeria, while Ghenea et al. [31] found MAR indices frequently exceeding 0.8 in isolates from intensive care and surgical units, reflecting the selective pressure of intensive antibiotic use. Ogefere & Idoko (2024) documented MAR indices from 0.42 to 1.00 in Klebsiella pneumoniae isolates from a tertiary hospital with higher resistance levels among inpatients compared to outpatients, emphasizing the resistance risks associated with clinical settings.

This current study revealed a significant direct correlation between antibiotic resistance levels and Benzalkonium chloride MIC values. In contrast, a p-value of 0.67 indicated no significant difference in Chlorhexidine MICs across different resistance profiles. In Iraq, Hassan et al. [32] attributed this variability to the presence of various virulence factors, such as biofilm formation and the acquisition of biocide resistance genes. Zhao et al. [33] reported statistically significant differences in Benzalkonium MIC values between extensively drug-resistant (XDR) and non-XDR Klebsiella pneumoniae strains, reinforcing the connection between antibiotic resistance and reduced susceptibility to disinfectants. These findings highlighted the need for tailored biocide application strategies to mitigate resistance development.

In this work, qacEΔ1 was detected in 62% of the isolates, while cepA was seen in 72% of them. Both genes were co-expressed in 46% of isolates. A similar study by Liu et al. [7] in China found qacEΔ1 in 64.9% and cepA in 93.2% of Klebsiella pneumoniae isolates, with 62.2% of isolates co-expressing both genes. Mikhaylovskaya et al. [34] reported qacEΔ1 and cepA prevalence in MDR Klebsiella pneumoniae isolates at 54% and 72%, respectively. In contrast, Chen et al. [35] found qacEΔ1 in 41.7% of isolates, with cepA detected in over 80%, highlighting regional variations in the prevalence of these resistance genes, which may be influenced by differing biocide usage protocols.

The distribution of qacEΔ1 showed no statistically significant association with resistance patterns (p-value = 0.874). However, cepA was significantly linked to an increased occurrence of XDR pattern (p-value = 0.0249), suggesting its role in contributing to extensive drug resistance. Afshar-Yavari et al. [36] did not find a significant relationship between cepA and resistance patterns in Klebsiella pneumoniae. Furthermore, there is a lack of sufficient studies exploring the relationship between qacEΔ1 and resistance patterns in Klebsiella pneumoniae isolates.

This study also examined the association between the presence of qacEΔ1 and cepA genes and antibiotic resistance. Our findings showed significant differences in resistance to Cefotaxime and Cefoperazone in qacEΔ1-positive isolates (p < 0.05), suggesting a contribution of this gene to increased resistance to mentioned antibiotics. In contrast, no statistically significant differences were observed between cepA-positive and cepA-negative isolates across tested antibiotics. These results align partially with Mihailovskaya et al. [33], who found no significant correlation between cepA and resistance to specific antibiotic classes but noted a strong association between qacEΔ1 and resistance to cephalosporins, carbapenems, and fluoroquinolones. Liu et al. [7] similarly found that qacEΔ1 and cepA-positive isolates exhibited significant resistance to a broad range of antibiotics.

We also could not find significant association between the biocide resistance genes qacEΔ1 or cepA and the MIC levels of benzalkonium chloride (BAC) and chlorhexidine (CHX). These findings are consistent with those of Vijayakumar et al. [13] in Saudi Arabia, who reported no significant correlation with multidrug-resistant strains of Klebsiella pneumoniae. However, contrasting evidence exists in other studies. Mihailovskaya et al. [34] observed that efflux pump genes, including qacEΔ1 and cepA, were associated with elevated MICs for BAC and CHX and these genes were frequently present in clinical isolates of MDR K. pneumoniae. Similarly, Afshar-Yavari et al. [36] found a significant relationship between the presence of cepA and high MICs for CHX in K. pneumoniae. These differing results highlight the complexity of biocide resistance mechanisms and the potential influence of environmental and clinical factors on the activity of efflux pumps.

Rational administration of biocides has been shown to increase the minimum inhibitory concentration of the tested agents. Applying disinfectants at concentrations lower than the inhibitory concentration may contribute to the spread of bacteria resistant to disinfectants, thereby increasing the risk of infection transmission to patients and the environment [37].

Conclusions

This study highlighted the extensive antibiotic resistance in Klebsiella pneumoniae, characterized by significant resistance to older antibiotics with a notable prevalence of multidrug resistant (MDR) and extensively drug resistant (XDR) strains. While the qacEΔ1 and cepA genes were frequently detected, no strong correlation was established between presence of these genes and biocide resistance. The variability in resistance patterns underscored the importance of understanding regional epidemiological data. These findings emphasized the critical need for effective infection control measures, including the rational use of biocides at concentrations ≥ 64 µg/mL and the mandatory identification of resistant strains to mitigate the risk of bacterial spread.

Recommendations

Further research is needed to fully understand the role of qacEΔ1 and cepA in resistance to BAC and CHX. Hospitals should enhance surveillance, investigate efflux pump genes, optimize biocide use, enforce strict antibiotic stewardship, and improve disinfection protocols to strengthen the prevention and treatment of multidrug-resistant Klebsiella pneumoniae. Additionally, tailored biocide strategies and focused research on bacterial resistance mechanisms to antibiotics and biocides are essential for developing effective prevention and treatment rules.

Data availability

Available on request from authors.

Abbreviations

CLSI:

Clinical and Laboratory Standards Institute

MIC:

Minimum inhibitory concentration

MDR:

multidrug resistant

XDR:

extensively drug resistant

PDR:

pan-drug resistant

MAR:

multiple antimicrobial resistance index

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Acknowledgements

None declared.

Funding

Open access funding provided by The Science, Technology & Innovation Funding Authority (STDF) in cooperation with The Egyptian Knowledge Bank (EKB).

This work didn`t receive any funding which was the main limitation in this study. More funding can help us to increase microbial sample size and test more disinfectants and antiseptics resistance mechanisms.

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Authors and Affiliations

  1. Department of Medical Microbiology & Immunology, Faculty of Medicine, Menoufia University, Shibīn al Kom, Egypt

    Amal F. Makled, Azza Z. Labeeb, Heba M. Moaz & Asmaa S. Sleem

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  1. Amal F. Makled
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  2. Azza Z. Labeeb
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  3. Heba M. Moaz
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  4. Asmaa S. Sleem
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Contributions

Amal F. Makled (AFM): conceptualization (lead); formal analysis (equal); supervision (lead); visualization (equal); writing of the original draft (equal). Azza Z. Labeeb (AZL): Conceptualization (equal); formal analysis (equal) supervision (equal); writing—review and editing (equal). Heba.M.Moaz (HMM):: practical methodology (equal); investigation (equal) Asmaa.S. Sleem (ASS): methodology (equal); supervision (equal); writing—review and editing (equal).

Corresponding author

Correspondence to Heba M. Moaz.

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Ethics approval and consent to participate

An informed written consent was obtained from each patient or from their guardians before enrollment in this study and the study protocol was approved by the Local Ethical Committee of Faculty of Medicine, Menoufia University (IRB 3/2022MICRO44).The study was conducted following the good clinical practice and the Declaration of Helsinki.

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Not applicable.

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The authors declare no competing interests.

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Makled, A.F., Labeeb, A.Z., Moaz, H.M. et al. Chlorhexidine and benzalkonium chloride: promising adjuncts in combating multidrug resistant Klebsiella pneumoniae in healthcare settings. BMC Infect Dis 25, 670 (2025). https://doiorg.publicaciones.saludcastillayleon.es/10.1186/s12879-025-10980-w

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Keywords

BMC Infectious Diseases

ISSN: 1471-2334

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