Escherichia coli, the type of bacteria responsible for 85 percent of diagnosed urinary tract infections, does show up in urine, according to Mayo Clinic. While E. coli bacteria are common in the intestines, sometimes they travel from the anus to the urethra and enter the urinary tract, causing UTIs.
As of 2015, the incidence of UTIs caused by drug-resistant E. coli has been rising since 2000, as Everyday Health explains. Scientists hypothesize, however, that these strains of E. coli don't originate with the human intestinal tract, but with infected chickens. UTIs typically manifest with symptoms that include burning urination and pelvic pain. If untreated, they pose the risk of permanent kidney damage.