ANTIBIOTIC RESISTANCE PATTERNS OF ESCHERICHIA COLI ISOLATED FROM THE URINARY TRACT OF PATIENTS ATTENDING ENUGU STATE UNIVERSITY TEACHING HOSPITAL PARKLANE ENUGU, NIGERIA

Chidimma Maureen Chukwueze1image, Chiemerie A. Ani2image, Kosisochukwu T. Okwunweze3image, Eberechukwu Grace Okoh1image, Chibueze. C. Nwobodo4image, Dennis Chinaza Egbo5image, 

Emmanuel Ifeanyi Obeagu*6,7image

1Department of Medical Laboratory Science, Faculty of Allied Health Sciences, Enugu State University of Science and Technology, Enugu, Nigeria. 2Department of Clinical Laboratory, Jennifer Etuh Medical Centre, Cross River state, Nigeria. 3Life Support Medical Center, 7 Bello Crescent Ilupeju Lagos, Nigeria. 4Goldlife Medical diagnostic Services, Enugu, Nigeria. 5Department of Biomedical Science, University of Salford, Manchester, England.

6Division of Haematology, Department of Biomedical and Laboratory Science, Africa University, Zimbabwe.

7Department of Molecular Medicine and Haematology, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.

 

Abstract

Background and objectives: Antimicrobial resistance among uropathogenic Escherichia coli represents a growing therapeutic challenge worldwide. This study investigated the antibiotic susceptibility pattern of E. coli isolated from patients presenting with urinary tract infections (UTIs) at Enugu State University Teaching Hospital (ESUT-TH), Enugu, Nigeria, and examined socio-demographic factors influencing antibiotic use. 

Subjects and methods: A total of 200 patients participated in this study, comprising 59 (29.5%) males and 141 (70.5%) females, predominantly aged 18 – 25 years (46.5%). E. coli isolated from the 200 urine samples were 45, representing a prevalence of 22.5%. Antibiotic susceptibility testing was performed using Kirby–Bauer disc diffusion method and high resistance rates were observed against ceftriaxone (84.4%), amoxicillin (84.44%), streptomycin (77.78%), chloramp-henicol (75.56%), ofloxacin (71.11%), meropenem (66.67%).

Results: Moderate resistance was recorded for ciprofloxacin (55.56%) and nitrofurantoin (57.78%) while gentamicin demonstrated the highest susceptibility (77.78%). Chi-square bivariate analysis revealed that though all respondents had used antibiotics, significant associations existed between gender and knowledge of antibiotics (p=0.028), previous UTI (p=0.010), and prior antibiotic treatment (p=0.012). 

Conclusions: The findings highlight substantial resistance to routine antibiotics and emphasize the need for periodic antimicrobial susceptibility testing, strengthened antibiotic stewardship and enhanced public health education to improve UTI management.

Keywords: Antibiotics, antimicrobial resistance, Escherichia coli, urinary tract infection.

 

INTRODUCTION

 

Urinary tract infections (UTIs) rank among the most prevalent bacterial infections found in both outpatient and inpatient environments globally. UTIs are infections found in the urethra, bladder, or kidneys and rank among the most prevalent infectious diseases globally, causing considerable morbidity1. Uro-pathogenic Escherichia coli (UPEC) continues to be the primary causative organism, responsible for most uncomplicated and a notable share of complicated UTIs2. The rising incidence of antimicrobial resistance in E. coli strains has turned into a significant worldwide public health issue, especially in low- and middle-income nations where empirical antibiotic usage is prevalent and laboratory-directed treatment is scarce. Antibiotics are essential in treating infectious diseases, thus enhancing patients’ quality of life and lifespan. Nevertheless, their inappropriate use and excessive reliance have led to the development of antimicrobial resistance (AMR), which arises when microorganisms become resistant to the impacts of antimicrobials2,3.

In Nigeria, inappropriate antibiotic use, self-medication, economic and geographical barriers to formal healthcare and limited antimicrobial surveillance have contributed to the rising burden of resistant uropathogens4. Local data on antimicrobial susceptibility patterns are therefore essential to guide effective treatment and reduce therapeutic failure. This study assessed the antibiotic susceptibility pattern of E. coli isolated from patients presenting with UTIs at Enugu State University Teaching Hospital (ESUTH), Enugu, Nigeria, and evaluated associated demographic and behavioral factors.

 

METHODS

 

Study area and design

This cross-sectional study conducted in a hospital setting took place at Enugu State University Teaching Hospital (ESUTH), located in Parklane, Enugu State, Nigeria. The study included patients aged 15 to 65 years who visited the General Out-patient Department (GOPD) with symptoms indicative of UTI and provided informed consent.

Sample size, sampling technique, collection and processing

Two hundred urine samples were gathered through random sampling methods. Sterile universal containers were used to collect midstream urine samples, which were processed within two hours after collection. Specimens were grown on Blood agar and CLED agar and incubated in aerobically at 37°C for 24 hours,

Identification of E. coli

Isolates were recognized through colony morphology, Gram staining, and conventional biochemical assays such as indole, catalase, and triple sugar iron (TSI) agar tests.

Antimicrobial susceptibility testing

Antibiotic susceptibility testing was conducted on Mueller–Hinton agar utilizing the Kirby–Bauer disk diffusion technique following Clinical Laboratory Standards Institute (CLSI) guidelines5. The antibiotics evaluated comprised ciprofloxacin, ofloxacin, peflox-acin, gentamicin, nitrofurantoin, streptomycin, ceftria-xone, amoxicillin, chloramphenicol, and meropenem.

Data analysis

Data were analyzed using SPSS version 27. Descriptive statistics were used to summarize demographic variables and susceptibility patterns. Chi-square test was applied to assess associations, with p< 0.05 considered statistically significant.

Ethical consideration

Ethical approval was obtained from the ESUT-TH Institutional Ethics Committee. Written informed consent was obtained from all participants. 

 

RESULTS

 

Among the 200 patients assessed, 45 tested positive for E. coli, indicating a prevalence rate of 22.5%, whereas 155 patients (77.5%) had UTIs resulting from different pathogens. This result shows that E. coli is a crucial causative factor of UTI within the study group, high-lighting its recognized position as a primary uro-pathogen. 

The E. coli isolates displayed significant resistance to several antibiotics, especially ceftriaxone and amoxi-cillin (84.44% each), followed by Strepto-mycin (77.78%) and chloramphenicol (75.56%). moderate resistance was noted with ciprofloxacin (55.56%) and nitrofurantoin (57.78%). Gentamicin showed the greatest sensitivity (77.78%) and the least resistance (22.22%), proving to be the most potent antibiotic of those evaluated. Two hundred (200) patients participated in this study, of which 141 (70.5%) were females and 59 (29.5%) were males. The majority of participants were aged 18–25 years (46.5%) and most respondents had secondary education (64%).

Chi-square bivariate analysis of the surveys revealed a statistically significant correlation between socio-demographic factors and knowledge and practices related to antibiotics. Gender showed a significant relation-ship with awareness of UTI treatment, past UTI infections, and earlier antibiotic usage (p<0.05). Age demonstrated notable associations with the length of antibiotic treatment and awareness of the antibiotics used (p=0.000). Educational credentials showed notable correlations with understanding of UTI, methods of transmission, antibiotic impacts, prescri-bing habits, length of treatment, perceived efficacy, and awareness of taken antibiotics (p≤0.037). In general, educational attainment was identified as the most significant predictor of proper antibiotic awareness and usage.

 

DISCUSSION

 

Resistance to antimicrobial agents is a worldwide issue that is progressively hindering efforts to manage infectious diseases3. This has been linked to the use of antimicrobials in human and agricultural practices. This study examined the antibiotic resistance trends of E. coli obtained from patients with urinary tract infections visiting ESUT-TH and evaluated socio-demographic factors related to antibiotic usage and awareness. Out of the 200 patients randomly chosen based on clinical presentation, females made up a larger share (70.5%) than males (29.5%). This distribution corresponds with known epidemiological trends of UTIs, since females are anatomically more susceptible to UTIs because of a shorter urethra and the closer location of the urethral opening to the perianal area, which aids bacterial colonization and movement into the urinary tract6. Most participants were between the ages of 18 and 25 (46.5%). This demographic is frequently linked to heightened sexual activity, acknowledged as a risk factor for UTIs, and also shows greater healthcare utilization, potentially clarifying their larger presence in this study7,8.Antibiotic susceptibility testing of the E. coli isolates revealed significant resistance to frequently prescribed antibiotics such as ceftriaxone, amoxicillin, strepto-mycin, and chloramphenicol. These results indicate potential indiscriminate use of antibiotics via self-medication and over-the-counter availability, leading to selective pressure for resistant bacteria. Despite gentamicin demonstrating the highest sensitivity (77.78%), this is not clinically reassuring, as it is a parenteral aminoglycoside that carries risks of nephro-toxicity and ototoxicity, rendering it less appropriate for the everyday outpatient treatment of uncomplicated UTIs9. The observed moderate sensitivity to frequently prescribed oral antibiotics like ciprofloxacin and nitro-furantoin indicates a reduction in the effectiveness of preferred empirical treatments, potentially leading to greater dependence on injectable or broader-spectrum antibiotics, raising treatment costs, toxicity risks, and further elevating the likelihood of antimicrobial resistance.

The significant resistance to meropenem (66.67%) raises alarms, considering carbapenems are crucial as last-resort treatments for multidrug-resistant infections10-13. Every participant indicated previous antibiotic usage, highlighting extensive exposure to antimicrobials. Notable correlations between socio-demographic factors like gender, age, educational attainment, and various antibiotic-related knowledge and practice indicators emphasize the impact of these factors on treatment behaviors and the possible development of the resistance14-16. Educational achiev-ement, specifically, showed extensive links to under-standing and proper antibiotic usage, high-lighting the significance of health literacy in managing anti-microbial resources effectively. 

 

CONCLUSIONS

 

This study highlights the complex dynamics of antibiotic resistance in E. coli strains responsible for UTIs. The differing resistance levels found for various antibiotics highlight the necessity for a careful strategy in choosing antibiotics and administering treatment. The elevated resistance levels to widely utilized antibiotics such as ceftriaxone and amoxicillin indicate the critical need for careful antibiotic stewardship practices to maintain the efficacy of these medications. In contrast, the comparatively reduced resistance levels to ciprofloxacin, nitrofurantoin, and gentamicin indicate that these antibiotics may remain useful treatment alternatives for UTIs in specific situations. In summary, the results highlight the growing issue of antimicrobial resistance in uropathogenic E. coli and emphasize the importance of regular susceptibility testing, enhanced antibiotic stewardship initiatives, and focused public health education to improve UTI treatment.

 

ACKNOWLEDGEMENTS

 

The authors would like to thank the University of the Witwatersrand, Johannesburg, South Africa to provide necessary facilities and support during this work.

 

AUTHOR’S CONTRIBUTIONS

 

Chukwueze CM: formal analysis, conceptualization, writing original draft. Ani CA:  formal analysis, critical review. Okwunweze KT: conceptualisation. Okoh EG: critical review. Nwobodo CC:  literature survey. Egbo DC: data organization. Obeagu EI: conceptualisation. Final manuscript was checked and approved by all authors.   

 

DATA AVAILABILITY

 

The associated author can provide the empirical data used to support the study's conclusions upon request.

 

CONFLICT OF INTEREST

 

There are no conflicts of interest in regard to this project.

 

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