Molecular study of antibiotic resistance gene among nitrofurantoin-resistant gram-negative bacteria isolates from pregnant women

Department of Biology, Faculty of Science, University of Kufa, Najaf, Iraq

^* Corresponding author: nabeel.tuwaij@uokufa.edu.iq

Abstract

In pregnancy, urinary tract infection (UTIs) is a significant risk factor for morbidity, and nitrofurantoin is a common UTI therapy. The goal was to identify gram-negative UTI isolates and detect antibiotic resistance genes. The research involved 350 pregnant women hospitalised to Al-Zahraa teaching hospital for children’s health and maternity between September and December 2024. Out of 250 pregnant patients, 200 (57.14%) urine samples were bacterial-free, whereas 150 (42.86%) were positive for gram-negative bacteria. The findings showed that 105 isolates (70%) were Escherichia coli, 33 (22%) were Klebsiella pneumoniae, 8 (5.3%) were Pseudomonas aeruginosa, 3 (2%) were Proteus mirabilis, and 1 (0.7%) were Acinetobacter baumannii. The disc diffusion Kirby-Bauer method determined 150 (100%) gramme negative bacteria’s nitrofurantoin sensitivity. 33 (22%) isolates were antibiotic-resistant, 16 (10.66%) intermediate, and 101 (67.33%) susceptible. PCR analysis showed that all 33 out of 33 (100%) gram negative isolates had Ribe, and AcrAB genes. Additionally, a significant prevalence of nfsA-2 genes was discovered in 32 out of 33 isolates (96.96%) the nfsA-1 gene in 78.78% (26/33) of the isolates. The NfsB gene was detected in 30 out of 33 (90.90%) distinct isolates of nitrofurantoin-resistant gram-negative bacteria. The Nucleic acid and amino acid sequence study of NfsA and Ribe genes in some local isolates of K. pneumoniae reveals variations in sequence when compared to other global strains with the same genes.