Background: Uncomplicated Urinary Tract Infections (UTIs) account for more than 100,000 inpatient admissions yearly. IDSA guidelines recommend Nitrofurantoin as first line therapy and recent FDA guidelines recommend against Fluoroquinolone (FQ) use due their side effects and growing resistance; however, Sulfamethoxazole/Trimethoprim (Bactrim) and Ciprofloxacin are still commonly used to treat uncomplicated UTIs. Therefore we hypothesized that patients at our institution may not be receiving appropriate empiric antibiotics for uncomplicated UTIs.
Methods: We reviewed the charts of patients 18 and over that were admitted to our institution with a primary or secondary diagnosis of uncomplicated UTI using ICD10 codes from 1/1/16-12/31/16. Males, diabetics, patients on dialysis, patients with anatomic or functional urologic abnormalities, patients with chronic indwelling Foley catheters or nephrostomy tubes, and concomitant infections were excluded. Variables collected for each visit were: age, symptoms (dysuria, burning on micturition, fever, nausea, altered mental status), all urinalysis results, urine culture growth and sensitivities, all antibiotics administered, allergies, and creatinine clearance as a marker of kidney function (calculated by us). We then analyzed the data to see which pathogens were most common, which antibiotics were administered initially and after sensitivities came back, and compared the sensitivities of these pathogens between Sulfamethoxazole/Trimethoprim, Ciprofloxacin, and Nitrofurantoin.
Results: During this time period, 46 patients were admitted to our institution with an uncomplicated UTI meeting the inclusion criteria but not the exclusion criteria. The initial antibiotic of choice in these patients was as follows: Ceftriaxone 27 (59%), Sulfamethoxazole/Trimethoprim 4 (9%), Ciprofloxacin 9 (20%), and Nitrofurantoin 1 (2%). Of these 46 patients, 29 (63%) had urine cultures grow pathogens with susceptibilities. The remaining cultures either had no growth, insignificant growth or were contaminated. Of the patients that had susceptible cultures (29), the pathogens were most sensitive to: Nitrofurantoin 23 (80%), followed by Sulfamethoxazole/Trimethoprim 20 (68%), and lastly Ciprofloxacin 17 (59%). 9 (20%) and 5 (11%) of these patients were transitioned to Sulfamethoxazole/Trimethoprim and Ciprofloxacin, respectively. None (0%) were transitioned to Nitrofurantoin after the cultures resulted.
Conclusions: At our institution, most hospitalized patients are not receiving Nitrofurantoin as empiric treatment for uncomplicated UTIs. The etiology of this is likely multifactorial. Our residents may not be aware of the 2016 FDA guidelines and may also not be aware of how to utilize anti-biograms to guide antibiotic management. Residents may not be aware of the change in AGS Beers Criteria such that Nitrofurantoin is now permissible for patients with GFR >30. One limitation of this study is that we were unable to determine if these patients were able to tolerate PO antibiotics. We believe there are multiple ways to improve empiric antibiotic selection. We have posted the most up to date anti-biograms in each housestaff workstation. We have also teamed with the Department of Infectious Disease and Antimicrobial Stewardship Pharmacist to implement these changes. We plan to create a system to identify patients admitted with uncomplicated UTIs to the hospital in real time in order to promote appropriate initial management.