(A) The log competitive infection urine titers of C3H/HeN mice infected with equal numbers of CFT073 or CFT073ΔfmlH over 28 days. 20 mice were infected over the course of 2 experiments, 7 developed chronic cystitis. (B) Tissue log competitive indexes of mice chronically infected with CFT073 vs. CFT073ΔfmlH or CFT073 vs. CFT073 as controls 28 dpi. Asterisk denotes p<0.05, Mann-Whitney test. (C) Complementation of fmlH restores virulence during chronic cystitis, 10 mice infected and 4 developed chronic cystitis. B and K represent the bladder and kidney titers 28dpi, respectively. (D) Rates of chronic cystitis development in C3H/HeN mice infected with CFT073 (11/29) or ΔfmlH (4/29) as represented by bladder bacterial burden 28dpi. Asterisk denotes p<0.05, Fisher’s exact test. Bars represent the mean of each data set.