Should you give antibiotic prophylaxis for an urodynamic study? Should you prescribe estrogen to treat urinary incontinence and voiding dysfunction? The two articles that we review below will try to shed some light on these two common but difficult questions.
Antibiotic Treatment to Prevent Urinary Tract Infections after Urodynamic Evaluation
Peschers UM, Kempf V, Jundt K, et al.
Int Urogynecol J. 2001;12:254–257.
Should you give antibiotic prophylaxis for an urodynamic study? Urinary tract symptoms, including frequency, urgency, urge incontinence and stress incontinence are common in women. The diagnosis of genuine stress incontinence and detrusor instability requires urodynamic evaluation. Prophylactic administration of antibiotics after urodynamics is used in many institutions to reduce the incidence of de novo urinary tract infection (UTI) after urodynamic testing. The few studies available on the subject could not demonstrate an advantage of routine antibiotic treatment.
This study was initiated to determine the efficacy of antibiotic (cotrimoxazole) administration after urodynamic testing to prevent UTI. In a single, blind, prospective, randomized study, 94 women who underwent an urodynamic evaluation were included. All the patients were prescreened to rule out UTI. After multichannel urodynamic testing, including two catheterizations, the women received a single dose of cotrimoxazole or placebo.
One week after the urodynamics, a clean-catch urine specimen was tested for UTI. Seventy women returned a urine specimen after 1 week: 2 of 37 (5.4%) in the treatment group and 2 of 33 (6.1%) in the placebo group had acquired a new UTI after urodynamics. One major and one minor adverse reaction to the antibiotic were reported. The most disappointing section of this study was that the power of the sample size was too small to draw conclusions as to the efficacy of prophylaxis.
The study design is good but the early interruption, with suboptimal sample size, constitutes a major limitation. The study did give some idea of the occurrence of infection after urodynamic studies, on the occurrence of asymptomatic bacteriuria with a negative dipstick, and on the low incidence of complications after testing, even in patients with untreated bacteriuria. The study also brings attention to the risks of repeat prophylactic antibiotic usage with no proven benefit. Serious anaphylactic reactions and the development of antibiotic resistance should always be considered before the indiscriminate use of antibiotics.
At the University of Pittsburgh Urodynamic Laboratory, we generally prophylax with a single pill of antibiotic after the urodynamic evaluation in patients without cardiac risk factors.
The Role of Estrogen Supplementation in Lower Urinary Tract Dysfunction.
Hextall A, Cardozo L.
Int Urogynecol J. 2001;12:258–261.
Should you prescribe estrogen to treat urinary incontinence and voiding dysfunction? The rationale for its use is that estrogen has an important physiological effect on the female lower urinary tract and its deficiency is often an etiological factor in lower urinary tract dysfunction. Urinary symptoms may therefore develop during the menstrual cycle, in pregnancy, and following menopause.
A survey of 937 women registered with a rural general practice found the prevalence of incontinence to be most common in the 45–55-year age group, a period which in most cases includes the climacteric. Of 2200 women with mean age of 61 years, 49% had some lower urinary tract symptoms, and 70% of these patients related the onset of their urinary leakage to their final menstrual period.
Estrogen deficiency, particularly when prolonged, is associated with a wide range of urogenital complaints, including frequency, nocturia, incontinence, UTI, and the “urge syndrome.” Estrogen supplementation subjectively improves urinary stress incontinence, but there is no objective benefit when given alone; however, estrogen given in combination with phenylpropanolamine may be clinically more useful. This has been reported in the literature but is no longer clinically relevant, as phenylpropanolamine has been shown to be associated with increased risks of cerebral vascular accidents. Therefore phenylpropanolamine is relatively contraindicated for clinical use.
Of 166 articles published in English since 1969 on the use of estrogen to treat incontinence, only 6 were reports on controlled trials, and 17 reported on uncontrolled series. The results of a meta-analysis showed that there were significant subjective improvements for all patients and for those with genuine stress incontinence. However, assessment of the objective parameters revealed that there was no change in the volume of urine lost.
There is valid clinical evidence accumulated over the past 30 years that hormone replacement therapy does appear to treat postmenopausal irritative urinary symptoms such as frequency and urgency, possibly by reversing urogenital atrophy, and there is also evidence to suggest that estrogens can provide prophylaxis against recurrent UTI. Further studies are required to determine the optimal type of estrogen, route of administration, and duration of therapy.
In our practice at the University of Pittsburgh, we generally do not prescribe oral estrogen therapy but would work in conjunction with the patient’s primary physician or the obstetrics/gynecology department when considering hormonal replacement. We do prescribe short courses of topical estrogen therapy preoperatively for stress incontinence and pelvic prolapse surgeries.