Bugs causing UTIs Bugs causing UTIs Bug (Bacteria only) Comments E. coli #1 leading cause of UTI S. saprophyticus #2 leading cause of UTI, common in young, sexually active women K. pneumoniae Proteus P. aeruginosa Common cause in patients with indwelling catheters Serratia Enterobacter cloacae E. faecalis Urinary tract infections cystitis ("bladder infection") dysuria polyuria suprapubic pain WBCs in urine no casts systemic symptoms (e.g. fever) uncommon pyelonephritis (infection reaches upper urinary tract or kidney) fever chills flank pain / costovertebral angle (CVA) tenderness WBC casts in urine hematuria Diagnosis positive leukocyte esterase test = bacterial UTI positive Nitrite test = Gram-Negative bacterial UTI Predisposing factors urinary catheterization diabetes pregnancy kidney surgery congenital defects vesicoureteral reflux (urine flows from bladder back to ureters) BPH Epidemiology women affected 10x more frequently than men shorter urethra proximity of urethra to anus colonization of vagina by fecal flora leading cause of UTIs is urinary catheters