Acute uncomplicated
cystitis is a lower
urinary tract infection occurring in the absence of anatomic or functional abnormalities of the urinary tract or any other complicating factors.The organism responsible is often an enterobacterium, especially Escherichia coli. What is the role of
antibiotic therapy for non-pregnant women with recurrent acute uncomplicated
cystitis? We reviewed the available evidence using the standard Prescrire methodology. A single oral dose of
fosfomycin trometamol is the
antibiotic of choice for treating an episode of acute uncomplicated
cystitis. Alternative
antibiotics are certain
fluoroquinolones or
co-trimoxazole (a fixed-dose combination of
sulfamethoxazole and
trimethoprim). For recurrent acute uncomplicated
cystitis, cranberry juice has modest efficacy in reducing the frequency of episodes. A number of non-
drug measures are typically proposed, although their effects are unproven: drinking sufficient fluids and urinating regularly; urinating after sexual intercourse; and avoiding spermicides. The strategy that results in the lowest
antibiotic exposure is a short course of
antibiotics for each episode of
urinary tract infection, initiated as soon as clinical symptoms appear. Long-term
antibiotic therapy is sometimes offered. According to one systematic review, women taking long-term prophylactic
antibiotic therapy had about 6 times fewer clinical recurrences than with placebo. According to one randomised trial, 3 g of
fosfomycin trometamol taken as a single dose every ten days reduced the frequency of recurrence, resulting in 0.14 episodes of
infection per year on average versus about 3 episodes with placebo (p < 0.001). The amount of
antibiotic used when
fosfomycin trometamol is taken every 10 days for 6 months is equivalent to treatment of 18 acute episodes of
cystitis. When
cystitis appears to be associated with sexual intercourse, two small randomised trials suggest that routine postcoital
antibiotic treatment is more effective than placebo and as effective as long-term
antibiotic therapy. Adverse effects, some of which can be serious, depend on the
antibiotic used. The development of resistance among enterobacteria is one argument for limiting the use of
antibiotics, in order to preserve their efficacy in serious
infections. In practice, the strategy that uses the fewest
antibiotics is to treat each episode as soon as the first clinical symptoms appear. Cases in which the frequency of recurrence warrants regular
antibiotic prophylaxis are rare. The optimal
antibiotic regimen in these cases has not been determined, either in clinical trials or by consensus.