Escherichia coli isolated from human polymicrobial bacteriuria are able to suppress in vitro interleukin production

Urinary tract infections are frequently polymicrobial and mainly due to Escherichia coli. Cystitis and pyelonephritis are usually associated with an inflammatory response. Uropathogenic E. coli posses the capabily to evade host defenses, modulating the innate immune response. The aim of this study was to determine if particular E. coli strains correlate with mixed bacteriuria and if the escape from the early host defense and a microbial synergy could be cause of the microbial association. We found significant correlations among polymicrobial urine, absence of pyuria and quinolone/fluoroquinolone susceptible E. coli isolates, and their major capability to suppress the interleukin-8 urothelial production with respect to the resistant strains.