Prior to the current update it appeared there was some evidence that cranberry juice may decrease the number of symptomatic UTIs over a 12 month period, particularly for women with recurrent UTIs. The addition of 14 further studies suggests that cranberry juice is less effective than previously indicated. Although some of small studies demonstrated a small benefit for women with recurrent UTIs, there were no statistically significant differences when the results of a much larger study were included. Cranberry products were not significantly different to antibiotics for preventing UTIs in three small studies. Given the large number of dropouts/withdrawals from studies (mainly attributed to the acceptability of consuming cranberry products particularly juice, over long periods), and the evidence that the benefit for preventing UTI is small, cranberry juice cannot currently be recommended for the prevention of UTIs. Other preparations (such as powders) need to be quantified using standardised methods to ensure the potency, and contain enough of the 'active' ingredient, before being evaluated in clinical studies or recommended for use.
[A study of non-antibiotic versus antibiotic prophylaxis for recurrent urinary-tract infections in women (the NAPRUTI study)].
Patient enrolment in the 'Non-antibiotic versus antibiotic prophylaxis for recurrent urinary-tract infections' (NAPRUTI) study was started in September 2005. In this study of women with recurrent urinary-tract infections we aim to investigate the effect of 12 months of non-antibiotic prophylaxis in comparison with antibiotic prophylaxis on the rate of recurrence of urinary-tract infections and the development of antibiotic resistance. The study consists of two interlinked, randomised, clinical non-inferiority trials. In one trial, 280 premenopausal women will receive either cranberry capsules (twice daily 500 mg) or standardised antibiotic therapy (once daily 480 mg trimethoprim-sulfamethoxazole). In the other trial, 280 postmenopausal women will receive either oral lactobacilli (twice daily a capsule with > 10(9) colony-forming units of Lactobacillus rhamnosus GR-1 and Lactobacillus reuteri RC-14) or standardised antibiotic therapy. Non-inferiority of non-antibiotic prophylaxis would be attractive given its potential to reduce the prevalence of microbial resistance to antibiotics significantly.