Antimicrobial Sensitivity Pattern of Bacterial Species Isolated From Pregnant Women With Urinary Tract Infection

Background: Urinary tract infections (UTIs) are among the most common bacterial infections in pregnant women and can lead to adverse maternal and fetal outcomes if untreated. Physiological changes in pregnancy increase susceptibility, and the emergence of antimicrobial resistance complicates management. Continuous monitoring of causative agents and their susceptibility profiles is critical for guiding effective therapy and preventing resistance escalation. Objective: To identify bacterial species causing UTIs in pregnant women and evaluate their antimicrobial sensitivity patterns to guide targeted therapeutic strategies. Methods: A cross-sectional study was conducted on 150 midstream urine samples collected from pregnant women attending Allied Hospital, Faisalabad. Samples were transported to the Microbiology Laboratory, Riphah International University, Faisalabad, and cultured on cysteine-lactose-electrolyte deficient agar (CLED). Bacterial identification was performed using standard biochemical tests. Antimicrobial susceptibility testing was carried out using the modified Kirby-Bauer disc diffusion method, following Clinical and Laboratory Standards Institute (CLSI) guidelines. Results: Out of 150 urine samples, 38.7% showed bacterial growth, while 61.3% yielded no growth. Escherichia coli was the most prevalent pathogen (39.7%), followed by Staphylococcus saprophyticus (20.7%), Enterococcus faecalis (13.8%), Klebsiella pneumoniae (10.3%), Proteus mirabilis (8.6%), and Pseudomonas aeruginosa (6.9%). Nitrofurantoin and fosfomycin demonstrated 100% susceptibility against E. coli but no activity against P. aeruginosa (0%). Piperacillin-tazobactam showed high effectiveness against K. pneumoniae (84%), P. mirabilis (80%), and P. aeruginosa (100%). For Gram-positive isolates, nitrofurantoin was effective against S. saprophyticus (92%) and E. faecalis (75%), while fosfomycin showed similar high activity. E. faecalis exhibited complete resistance to ampicillin and amoxicillin (0%). Conclusion: The study highlights E. coli as the predominant uropathogen in pregnancy-associated UTIs and emphasizes nitrofurantoin, fosfomycin, and piperacillin-tazobactam as the most effective treatment options. Routine susceptibility testing is essential to optimize maternal care and curb antimicrobial resistance.