Antibiotic prophylaxis in prevention of urinary tract infections caused by removal of a bladder catheter in children

Urinary tract infections are frequently seen in childhood, presenting by a
range of symptoms. It is a well know believe that urinary tract infections can
be caused by the removal of a bladder catheter. There are several hypotheses
about this mechanism: during removal of a catheter micro-lesions in the bladder
and urethra epithelium can be caused, which may act as a porte d'entree for
micro-organisms, or possibly, there's shortly a less efficient bladder
function.
Often antibiotics are prescribed as prophylaxis during the removal of a bladder
catheter in children, although there is no scientific evidence.

The goal of this study is to determine whether a short course of
amoxicillin/clavulanic acid reduces the number of urinary tract infections in
children that have been catheterized during a short period.

Randomized, double-blind placebo-controlled multicenter clinical trial.
The study will be started in the Onze Lieve Vrouwe Gasthuis and VU Medical
Center, followed by the Sint Lucas Andreas Hospital, Zaans Medical Center and
Kennemer Gasthuis. During a maximum of two years children will be recruited
between 0 and 18 years, that need a bladder catheter more than two hours, less
than 7 days. Informed consent will be needed. Exclusion criteria: pre-existent
use of antibiotics, renal function failure, allergy to amoxicillin or
symptomatic bacteriuria.
Demographics will be listed and parents will be asked to fill in a
questionnaire. There will be block randomisation by means of envelopes.
Two hours before the removal of the catheter the short course
amoxicillin/clavulanic suspension, or placebo, will be started; the course will
be curing 48 hour, 50/12,5 mg/kg in 3 times, with a maximum of 3dd500/125mg.
Parents and their children will be asked to fill in other questionnaires after
1 and 3 weeks, and to collect urine, which will be analyzed and be cultured.
For statistal analysis a Fisher's exact test will be used. The study is
designed to detect a possible difference of 20% in the occurence of urinary
tract infections between the antibiotica and placebo-group, with a 95%
confidence interval and a power of 80%, assuming an a priori change of 5% of
the occurence of an urinary tract infeciton in children, caused by the removal
of a bladder catheter. Following calculation with the Fisher's exact test, 47
patients a group, meaning a total of 94 patients have to be included.

amoxicillin/clavulanic acid (50/62,5mg/kg, max. 3 times a day 500/125mg) versus
placebo

The burden will be having to take the antibiotics; usually this is not a
problem, because of the sweet taste of amocillin/clavulanic acid. Possibly
there is the risk of developing diarrea as a side-effect.