Title:  Randomized Controlled Trial of Single Dose Aminoglycosides for Acute Uncomplicated Cystitis in Emergency Medicine

Author(s): Jacob Sieger, DO; Joe Dombroski, DO; Vincent Peyko, PharmD

Email: Jsieger@mercy.com

Introduction: UTI infections are commonly treated with beta-lactams, requiring a week-long prescription as an outpatient. Alternative agents, such as sulfamethoxazole-trimethoprim and fluoroquinolones, can also be used; all of these options have seen growing rates of antibiotic resistance. While aminoglycosides have been an appropriate choice to treat most UTIs, use has decreased by 41% between 2002-2009, mainly due to renal toxicity associated with multi-day regimes as well as the advent of newer antibiotics. In a systematic review Goodlet et al reported single dose aminoglycosides for UTI exhibited a pooled microbiological cure rate of 94.5+4.3%, suggesting likely beneficial use in emergency medicine.  The purpose of our study was to compare standard of care with single-dose aminoglycoside treatment for ED presentations of cystitis.

Methods: Randomized enrolled patients had to be at least 18 years of age, woman, premenopausal, and non-pregnant, with clinical signs of UTI and nitrite positive urine in the ED. Patients were contacted by telephone at 7 and 30 days and asked about clinical resolution of their urinary tract infection: pain with urination, frequency, or urgency. Adverse effects, missed doses, or return to a healthcare provider for any reason by day 30 following treatment were also obtained.

Results: Age and weight of the N=34 patients enrolled in both the single dose aminoglycoside and standard of care groups were similar, 33+10 years and 78+21kg. Drugs in the standard of care group were typically nitrofurantoin or cefdinir.  Average dose of aminoglycoside was 331+61 mg. Lost to follow-up were n=7 in the standard of care group and n=4 in the single dose aminoglycoside group.  Among those with 7-day telephonic follow-up, self-reported symptom resolution was 83.3% (25/30) among aminoglycoside treated patients and 48.1% (13/27) in the standard of care group (X² = 7.917, p = 0.005).  No return to hospital were noted among the aminoglycoside patients; in the standard of care group, return rate was 17.6% (n=6/34, Fisher’s Exact test = 0.025).  Eight patients in the standard of care group, 29.6% (n=8/27), missed doses; average number of missed doses was 7+4.  A nonsignificant higher rate of adverse events was noted in the aminoglycoside group, attributed largely to IM injection site soreness which resolved.

Discussion/Conclusion: Single dose aminoglycosides for acute uncomplicated cystitis in premenopausal, nitrite positive women is an appropriate UTI treatment.  Although transient injection site soreness was reported, symptom resolution, treatment failure and drug compliance all favored aminoglycoside over standard of care.