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Assessment of Biofilm Forming Capability and Antibiotic Resistance in Proteus mirabilis Colonizing Indwelling
Abstract:
<b>Background and Objective:</b> Urinary tract infections from the use of an indwelling urinary catheter are one of the most common infections caused by <i>Proteus mirabilis</i>. Due to their biofilm-producing capacity and the increasing antimicrobial resistance in this microorganism, this study aimed to determine the prevalence, biofilm-producing capacity, antimicrobial resistance patterns, multidrug resistance and plasmid mediated resistance of the recovered isolates. <b>Materials and Methods:</b> A total of 50 urinary samples were collected from May to August, 2018 from patients on indwelling urinary catheters. Using routine microbiological and biochemical methods, 37 <i>P. mirabilis</i> were isolated. Biofilm forming capability was determined among the isolates using the tube method while antimicrobial susceptibility and plasmid curing were also performed. <b>Results:</b> All isolates were biofilm producers with 17(46%) being moderate producers while 20(54%) were strong biofilm formers. The study isolates exhibited a high resistance rate to empiric antibiotics, including ceftazidime (75.8%), cefuroxime (54.5%), ampicillin (69.7%) and amoxicillin-clavulanic acid (51.5%). Low resistance was seen in the fluoroquinolones, gentamicin and nitrofurantoin. Plasmid curing experiment revealed that most isolates lost their resistance indicating that resistance was borne on plasmids. Plasmid carriage is likely the reason for the high MDR rate of 56.8% observed. <b>Conclusion:</b> These findings necessitate the provision of infection control programs which will guide and implement policies.
Insights
Proteus mirabilis from catheter-associated urinary tract infections frequently forms biofilms and shows high antimicrobial resistance, often plasmid-mediated. Enhanced infection control programs are essential to manage these resistant bacteria.
Area of Science:
- Microbiology
- Infectious Diseases
- Antimicrobial Resistance
Background:
- Urinary tract infections (UTIs) are common in patients with indwelling urinary catheters.
- Proteus mirabilis is a frequent cause of catheter-associated UTIs.
- This bacterium exhibits significant biofilm-producing capacity and increasing antimicrobial resistance.
Purpose of the Study:
- To determine the prevalence of Proteus mirabilis in catheter-associated UTIs.
- To assess the biofilm-producing capacity of P. mirabilis isolates.
- To investigate antimicrobial resistance patterns, multidrug resistance (MDR), and plasmid-mediated resistance.
Main Methods:
- Collected 50 urinary samples from patients with indwelling urinary catheters.
- Isolated and identified 37 P. mirabilis strains using microbiological and biochemical methods.
- Assessed biofilm formation via the tube method, antimicrobial susceptibility, and plasmid curing.
Main Results:
- All 37 P. mirabilis isolates were biofilm producers (46% moderate, 54% strong).
- High resistance rates observed for ceftazidime (75.8%), ampicillin (69.7%), and cefuroxime (54.5%).
- Plasmid curing indicated that resistance was plasmid-borne, contributing to a 56.8% multidrug resistance rate.
Conclusions:
- Proteus mirabilis isolates from catheter-associated UTIs demonstrate significant biofilm formation and antimicrobial resistance.
- Plasmid-mediated resistance is a key factor in the high prevalence of multidrug resistance.
- Findings underscore the need for robust infection control programs to manage these resistant pathogens.
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