Both Allergy and Resistant Antibiotic Sensitivity #503 Impact of antibiotic allergy and resistance on oral first-line antibiotic treatment choice for recurrent urinary tract infections in older women Yuefeng (Rose) Wu and Philippe E. Zimmern, M.D. Department of Urology, The University of Texas Southwestern Medical Center Introduction Baseline demographics Urinary tract infection lifetime risk for women >50%1 Recommended effective oral antimicrobial agents with minimal adverse effects include trimethoprim-sulfamethoxazole, nitrofurantoin, and fluoroquinolones.2 Obstacles in the management of RUTIs include: antibiotic allergies, upward trend of antimicrobial resistance, and drug-induced adverse events. Nitrofurantoin is not recommended for women with creatinine clearance <30mL/min or for long-term bacterial suppression. 3 N=86 Mean ± SD Age 77.9 ± 7.8 BMI 24.4 ± 6.1 Race Caucasian 94% (81/86) Other 6% (5/86) Controlled adult-onset Diabetes Mellitus 10% (9/86) BUN 17.3 ± 8.3 Creatinine 0.84 ± 0.29 eGFR >60mL/min 65% >30mL/min 94% No. known allergies to medications 3.5 ±3.9 No. allergies to antibiotics 1.6 ± 1.8 No. antibiotic resistances 4.3 ±3.5 Objective Results N=86 Percent women either allergic and/or had resistance to: TMP-SMX 77% (66/86) Fluoroquinolones 56% (48/86) Nitrofurantoin 35% (30/86) 29% of women who were allergic and/or resistant to TMP-SMX and fluoroquinolones were neither allergic nor resistant to nitrofurantoin. Women allergic/resistant to TMP-SMX or fluoroquinolones had significantly more antibiotic resistances than those sensitive. No significant difference in number of antibiotic resistances for women sensitive vs. allergic/resistant to Nitrofurantoin. To review the rate of antibiotic allergy and resistance in older women with recurrent urinary tract infections (RUTIs) as determinants for a suitable oral antibiotic treatment choice. Materials and Methods IRB-approved study Retrospective chart review of prospectively maintained database of women with uncomplicated RUTIs who were refractory to multiple courses of antibiotic therapy. RUTI defined as ≥3 uncomplicated UTI in 12 months; midstream urine bacterial count of >105 CFU/mL Exclusion: children, women <65 years old, women with no antibiotic susceptibility profiles available for review Data collected: demographics, known drug allergies, BUN, creatinine, eGFR, antibiotic susceptibility; from electronic medical record (EPIC), most recent available test results. Antibiotics analyzed: trimethoprim-sulfamethoxazole (TMP-SMX) + other sulfonamides Fluoroquinolones (ciprofloxacin, levofloxacin, moxifloxacin) Nitrofurantoin Summary of antibiotic allergy and/or resistance findings, N=86 Allergy Only Resistant Only Both Allergy and Resistant Antibiotic Sensitivity TMP-SMX* 28 25 13 20 Fluoroquinolone** 12 29 7 38 Nitrofurantoin 14 4 56 *Trimethoprim-sulfamethoxazole **Includes ciprofloxacin, levofloxacin, and moxifloxacin Conclusion This study reaffirms that due to allergy and/or antibiotic resistance several first-line antibiotics are not available for many Caucasian women with RUTIs. Women are equally likely to be sensitive to Nitrofurantoin regardless of number of other antibiotic allergies/resistances. In a significant number of women, nitrofurantoin is the only viable alternative in the management of these more complex patients. References Aydin, A. et al. Recurrent urinary tract infections in women. Int Urogynecol J, 26: 795, 2015. Albert, X. et al. Antibiotics for preventing recurrent urinary tract infection in non-pregnant women. In: Cochrane Database of Systematic Reviews. Edited by T. C. Collaboration. Chichester, UK: John Wiley & Sons, 2004 By the American Geriatrics Society Beers Criteria Update Expert, P.: American Geriatrics Society 2015 Updated Beers Criteria for Potentially Inappropriate Medication Use in Older Adults. J Am Geriatr Soc, 2015