We read with interest the recent study by Cox et al in the September 2017 issue of CUAJ.1 Authors describe a series of 20 neurogenic bladder patients on intermittent self-catheterization treated with intravesical instillations of gentamicin in order to reduce recurrent urinary tract infection (UTI). The authors state that use of intravesical gentamicin reduced the frequency of UTI from four episodes in six months to one in six months. Additionally, less telephone encounters and fewer hospital visits were recorded and other antibiotic usage decreased, with minimal adverse events noted. A secondary aim was to assess microbiological resistance patterns: the rate of overall resistance to gentamicin did not increase.
Of the 20 patients involved, 59.1% were male, and spinal cord injury (SCI) accounted for 63.6% of those included, with 13.6% of patients having multiple sclerosis (MS). The mean age of participants was 37.5 years.
The authors emphasize the reduction in hospitalizations, emergency room visits, and telephone encounters as a result of this novel treatment. Specific to the SCI and MS patients, this is a very important point, as bladder function frequently affects quality of life.2 It should be acknowledged by the authors that no validated questionnaire specific to the neurogenic bladder patient was included to assess the quality of life improvement with respect to bladder health after intravesical gentamicin treatment. In our neuro-urology unit, we routinely use the SF Qualiveen questionnaire3 at baseline assessment of all SCI and MS patients in order to determine the impact of bladder symptoms on quality of life pre and post any bladder-specific treatment. One of the domains tested is “frequency of limitations” and enquires about life being regulated by bladder problems: if intravesical gentamicin reduces hospital visits and UTI, then overall quality of life due to bladder health is presumably better in the neurogenic patient and should be measured objectively.
Additionally, although data pertaining to intravesical gentamicin use is limited in cases of recurrent UTI, case reports exist in the U.K. literature. Naderi et al have reported successful treatment of recalcitrant E. coli UTI in an 81-year-old diabetic female with multiple allergies following a five-day course of daily intravesical gentamicin.4
Finally, although no significant adverse effects were reported, the authors do not address the hypothetical risk of systemic absorption. Whatley et al have reported on the proposed risk of systemic absorption in ENT patients undergoing nasal irrigations with gentamicin.5
References
- 1.Cox L, He C, Bevins J, et al. Gentamicin bladder instillations decrease symptomatic urinary tract infections in neurogenic bladder patients on intermittent catheterization. Can Urol Assoc J. 2017;11:E350–4. doi: 10.5489/cuaj.4434. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 2.Costa P, Perrouin-Verbe B, Colvez A, et al. Quality of life in spinal cord injury patients with urinary difficulties. Development and validation of qualiveen. Eur Urol. 2001;39:107–13. doi: 10.1159/000052421. [DOI] [PubMed] [Google Scholar]
- 3.Bonniaud V, Bryant D, Parratte B, et al. Development and validation of the short form of a urinary quality of life questionnaire: SF-Qualiveen. J Urol. 2008;180:2592–8. doi: 10.1016/j.juro.2008.08.016. [DOI] [PubMed] [Google Scholar]
- 4.Naderi K, Urwin G, Casey RG. Intravesical gentamicin treatment of recurrent Escherichia coli urinary tract infections in a patient with multiple antibiotic allergies. J Clin Urol. 2014;7:364–6. doi: 10.1177/2051415813508545. [DOI] [Google Scholar]
- 5.Whatley WS, Chandra RK, MacDonald CB. Systemic absorption of gentamicin nasal irrigations. Am J Rhinol. 2006;20:251–4. doi: 10.2500/ajr.2006.20.2855. [DOI] [PubMed] [Google Scholar]