The Significance of Age and Causative Bacterial Morphology in the Choice of an Antimicrobial Agent to Treat Acute Uncomplicated Cystitis.

Differentiating patients by age and causative bacterial morphology might aid in making the appropriate choice of antimicrobial agent when treating acute uncomplicated cystitis. In this retrospective analysis, the non-susceptibility rates of the causative bacteria to cefcapene-pivoxil (CFPN-PI) and levofloxacin (LVFX) were determined after dividing patients with acute uncomplicated cystitis by age group (15-54 and 55-74 years old) and by bacterial morphology: gram-positive cocci (GPC) or gram-negative rod (GNR). The overall non-susceptibility rates for CFPN-PI and LVFX were 19.4% and 15.3%, respectively. When the subjects were divided by age, only the non-susceptibility rate for LVFX in the younger group significantly decreased (to 8.7%). When the groups were divided by both age and bacterial morphology, the younger GNR group had non-susceptibility rates of 6.9% to CFPN-PI and 7.8% to LVFX, whereas the younger GPC group showed 10.2% non-susceptibility to LVFX. The older GNR group showed 9.8% non-susceptibility to CFPN-PI, while the older GPC group showed 7.2% non-susceptibility to LVFX. All the non-susceptibility rates were lower than 10.2% in the sub-divided groups. Differentiating patients by age and the morphology of causative bacteria can aid in making the appropriate choice of antimicrobial agent and may improve treatment outcomes in patients with acute uncomplicated cystitis.