The gene profile of Enterobacteriaceae virulence factors in relation to bacteriuria levels between the acute episodes of recurrent uncomplicated lower urinary tract infection.

OBJECTIVES: The pathogenic potential of uropathogens isolated between acute episodes of recurrent lower urinary tract infection (rLUTI) is studied insufficiently. The objectives were to determine the spectrum of virulence genes of Enterobacteriaceae cultured between acute episodes of rLUTI at various levels of bacteriuria. METHODS: Bacteriological examinations of 169 premenopausal women's midstream urine with rLUTI were performed between acute episodes of UTI. Sixty-two strains of Enterobacteriaceae at concentrations 102-108 CFU/ml were analyzed for the presence of papA, papE/F, papGII, afa, bmaE, iutA, feoB, fyuA, kpsMTII, and usp virulence factors genes' (VFGs) fragments. RESULTS: In all strains VFGs were found with numbers from 1 to 10. Four VFGs were found at all levels of bacteriuria (from 102 to 107-8) in most strains (>50%): papGII, feoB, fyuA, usp. In total, 28 significant Pearson contingency coefficient (PCC) were determined. Each of the genes, papA, papE/F, usp, was found more often in uropathogens from patients with a higher level of leukocyturia. CONCLUSIONS: The inter-episode period in rLUTI is associated with varying levels of bacteriuria of enterobacteria. Since enterobacteria virulent potential could be determined at all levels of bacteriuria, there is at all levels of bacteriuria a potential risk for recurrence of LUTI.

Does Escherichia coli have pathogenic potential at a low level of bacteriuria in recurrent, uncomplicated urinary tract infection?

BACKGROUND: In recurrent uncomplicated lower urinary tract infection (uLUTI), bacteriuria below 103 colony-forming units (CFU)/mL is not usually investigated. OBJECTIVE: To determine the molecular-genetic characteristics of the pathogenic potential of Enterobacteriaceae isolated between episodes of recurrent uLUTI at bacteriuria of 102 CFU/mL. MATERIALS AND METHODS: Midstream urine samples taken from 169 women between episodes of recurrent uLUTI were examined on six media. Fifteen Enterobacteriaceae strains at a low level of bacteriuria (102 CFU/mL) were analysed by polymerase chain reaction for the presence of the following virulence factor genes (VFGs): papA, papE/F, papGII, afa, bmaE, iutA, feoB, fyuA, kpsMTII and usp. RESULTS: All 169 patients had leukocyturia and asymptomatic bacteriuria, and 62 of these cases were due to enterobacteria: 102 CFU/mL, 15 strains (24.2%); 103 CFU/mL, 10 strains (16.1%); and >103 CFU/mL, 37 strains (59.7%). VFGs were verified in all 15 strains at a low level of bacteriuria (102 CFU/mL): one VFG (papGII) was found in two strains of Klebsiella spp., three VFGs were found in one strain of Enterobacter spp.xst, and between four and nine VFGs were found in the remaining 12 strains. Among the VFGs, papGII (93.3%), usp (86.7%), feoB (80.0%), fyuA (80.0%) and kpsMTII (73.3%) predominated. A significant correlation was found between the presence of papE (P=0.02) and usp (P=0.025) and a relapse rate of more than four recurrences in 1 year. An association was found between leukocyturia and the presence of papE (P=0.031) and papGII (P=0.031). CONCLUSION: Enterobacteria isolated from the urine of female patients with recurrent uLUTI at a low level of bacteriuria (102 CFU/mL) have a wide spectrum of VFGs, which may play a role in maintaining chronic inflammation of the lower urinary tract.