Molecular Detection of Esp and qnrA Genes in Biofilm-Producing Multidrug-Resistant Proteus mirabilis from Catheter-Associated Urinary Tract Infections in Bauchi Metropolis, Nigeria
A. U. Abdullahi *
Department of Microbiology, Abubakar Tafawa Balewa University, ATBU, Bauchi, Nigeria.
A. Umar
Department of Microbiology, Abubakar Tafawa Balewa University, ATBU, Bauchi, Nigeria.
A. Magaji
Department of Microbiology, Federal University of Health Sciences, Azare (FUHSA), Bauchi State, Nigeria.
Z. M. Kabeer
Biology Department, School of Science, Aminu Saleh College of Education, Azare, Bauchi State, Nigeria.
S. Ismai’l
Department of Microbiology, Abubakar Tafawa Balewa University, ATBU, Bauchi, Nigeria.
T. Inusa
Department of Microbiology, Abubakar Tafawa Balewa University, ATBU, Bauchi, Nigeria.
Y. Saheed
Department of Microbiology, Yobe State University, Damaturu, Nigeria.
F.M. Ado
Department of Microbiology, University of Abuja, Abuja, Nigeria.
A. Usman
College of Nursing Science, Maiduguri, Borno State, Nigeria.
A. B. Zamo
Department of Microbiology and Immunology, Federal University of Health Sciences Teaching Hospital, Azare (FUHSTHA), Bauchi State, Nigeria.
I. Mustapha
Department of Medical Laboratory Technicians, Galtima Mai Kyari College of Health Technology, Nguru, Yobe State, Nigeria.
H. S. Musa
National Health Insurance Authority, Bauchi State Office, Bauchi State, Nigeria.
M. Y. Iliyasu
Department of Microbiology, Abubakar Tafawa Balewa University, ATBU, Bauchi, Nigeria.
U. S. Abdullahi
Department of Veterinary Medicine, Abubakar Tafawa Balewa University, ATBU, Bauchi, Nigeria.
A. F. Umar
Department of Microbiology, Abubakar Tafawa Balewa University, ATBU, Bauchi, Nigeria.
*Author to whom correspondence should be addressed.
Abstract
Background and Aims: Catheter-associated urinary tract infections may involve multidrug-resistant (MDR) Proteus mirabilis capable of biofilm formation. Molecular data on such isolates in Bauchi Metropolis, Nigeria, are limited. This study investigated antimicrobial resistance, biofilm formation and PCR detection of esp-targeted and qnrA amplicons in P. mirabilis from catheterised patients.
Methods: In this cross-sectional, laboratory-based study, 227 urine specimens were collected from catheterised inpatients at Abubakar Tafawa Balewa University Teaching Hospital (n = 130) and Specialist Hospital Bauchi (n = 97) between January and July 2025. Isolates were identified using culture characteristics, microscopy and biochemical tests. Disc diffusion was used for antimicrobial susceptibility testing, and the tube method was used to assess biofilm formation. Five MDR, biofilm-producing isolates underwent conventional PCR.
Results: Among 173 microbial isolates, 12 (6.9%) were P. mirabilis (six each from ATBUTH and SHB). A higher proportion of isolates was recovered from female patients (58.3%) and from patients aged ≥60 years (83.3%), with more isolates recovered following longer durations of catheterisation (≥30 days: 33.3%). The isolates showed high resistance to amoxicillin (66.7-100%), cefotaxime (83.3-100%), ceftazidime (66.7-83.3%), cotrimoxazole (66.7-100%), and fluoroquinolones (66.6-100%) based on hospital-specific denominators (ATBUTH n=6, SHB n=6). Among the five biofilm-producing MDR isolates subjected to molecular analysis, Esp was detected in 5/5 (100%) and qnrA in 4/5 (80.0%). These results apply only to the tested subset and cannot be generalised to all 12 P. mirabilis isolates
Conclusion: Multidrug-resistant, biofilm-producing P. mirabilis with Esp-targeted and qnrA amplicons were detected among catheterised patients in Bauchi. These findings underscore the need for strengthened catheter care, antimicrobial stewardship and continued surveillance to control CAUTIs.
Keywords: Proteus mirabilis, biofilm, multidrug resistance, Esp, qnrA, catheter-associated UTI