An experimental study was conducted on 3 consecutive 12-hour days to determine if selected physical properties of feeding tubes (material and diameter) affect tube clogging. Effectiveness of three irrigant fluids (cranberry juice, Coca-Cola, and water) in preventing tube clogging was studied. One hundred eight tubes were connected to gravity flow feeding bags containing isotonic enteral formula; 54 polyurethane and 54 silicone tubes were equally divided as to external diameters of 8 French (Fr), 10 Fr, and 12 Fr. At 4-hour intervals, flow regulators on the feeding bags were adjusted to a rate of 50 ml/hour. Fluid volumes delivered per minute were measured for each tube at 2-hour intervals. One set of tubes at each station was irrigated periodically with cranberry juice, Coca-Cola, or water. On each of the 3 days, analyses revealed significant, p less than .05, effects for tube material, cranberry juice contrasted with Coca-Cola and water as irrigants, and time. Polyurethane was consistently superior to silicone as a tube material, and cranberry juice was consistently inferior to both Coca-Cola and water as an irrigant. Tube diameter had no significant effect on the incidence of tube clogging.

Cranberry juice has been widely used for the treatment and prevention of urinary tract infections and is reputed to give symptomatic relief from these infections. Attempts to account for the potential benefit derived from the juice have focused on urine acidification and bacteriostasis. In this investigation it is demonstrated that cranberry juice is a potent inhibitor of bacterial adherence. A total of 77 clinical isolates of Escherichia coli were tested. Cranberry juice inhibited adherence by 75 per cent or more in over 60 per cent of the clinical isolates. Cranberry cocktail was also given to mice in the place of their normal water supply for a period of 14 days. Urine collected from these mice inhibited adherence of E. coli to uroepithelial cells by approximately 80 per cent. Antiadherence activity could also be detected in human urine. Fifteen of 22 subjects showed significant antiadherence activity in the urine 1 to 3 hours after drinking 15 ounces of cranberry cocktail. It is concluded that the reported benefits derived from the use of cranberry juice may be related to its ability to inhibit bacterial adherence.

Strains of uropathogenic E. coli are responsible for approximately 90% of community-acquired, uncomplicated cystitis, and fimbriae represent the adhesive factors enabling E. coli to be anchored to uroepithelial cells in the first step of the infectious process. Recently, a few studies have shown that a correlation between the consumption of cranberry (Vaccinium macrocarpon) and prevention of UTI is related to the ability of proanthocyanidins to reduce the bacterial adhesion to uroepithelial cells. In this study we evaluate the inhibitory activity of urine of healthy women treated with tablets containing cranberry extract on the adhesiveness of E. coli to uroepithelial human cells. Two groups of 12 female volunteers each, aged between 18 and 65 years, were enrolled, one group with negative history and one group with positive history of recurrent cystitis. Subjects were treated with the active product or placebo in a random, cross-over, double-blinded sequence for one week in each of the two treatment sequences. Urine samples were collected at the beginning and the end of each study period. Tests of bacterial adhesiveness were performed with two strains of E. coli (ATCC 25922 and ATCC 35218) on HT1376 human bladder carcinoma cells. Significant reductions of bacterial adhesiveness were observed in women who received cranberry extract (-50.9%; p less than 0.0001), regardless of their medical history and the treatment period in the cross-over sequence. No changes were observed with placebo (-0.29%; n.s.). This ex-vivo study showed that the assumption of cranberry extract in suitable amounts can have an anti-adhesive activity on uropathogenic E. coli.

OBJECTIVE: To determine the effect of regular intake of cranberry juice beverage on bacteriuria and pyuria in elderly women.

DESIGN: Randomized, double-blind, placebo-controlled trial.

SUBJECTS: Volunteer sample of 153 elderly women (mean age, 78.5 years).

INTERVENTION: Subjects were randomly assigned to consume 300 mL per day of a commercially available standard cranberry beverage or a specially prepared synthetic placebo drink that was indistinguishable in taste, appearance, and vitamin C content but lacked cranberry content.

OUTCOME MEASURES: A baseline urine sample and six clean-voided study urine samples were collected at approximately 1-month intervals and tested quantitatively for bacteriuria and the presence of white blood cells.

RESULTS: Subjects randomized to the cranberry beverage had odds of bacteriuria (defined as organisms numbering > or = 10(5)/mL) with pyuria that were only 42% of the odds in the control group (P = .004). Their odds of remaining bacteriuric-pyuric, given that they were bacteriuric-pyuric in the previous month, were only 27% of the odds in the control group (P = .006).

CONCLUSIONS: These findings suggest that use of a cranberry beverage reduces the frequency of bacteriuria with pyuria in older women. Prevalent beliefs about the effects of cranberry juice on the urinary tract may have microbiologic justification.

Abstract: Urinary ionized calcium was determined by a calcium activity electrode in 32 normal persons and in 54 patients with calcium-containing renal stones and without urinary tract infection. It was found to be 38 per cent higher in patients with calcium-containing renal stone in comparison to normal persons. However, this was not statistically significant. No consistant change in total or ionized calcium excretion was produced in normal volunteers by the administration of as much as 5 pints of cranberry juice. In patients with renal stones, the urinary ionized calcium was reduced during the cranberry juice ingestion by 50 per cent, which was statistically highly significant.

This study evaluated the antibacterial efficacy of the consumption of cranberry capsules vs. placebo in the urine of healthy volunteers. A first double-blind, randomised, crossover trial involved eight volunteers who had followed three regimens, with or without cranberry, with a wash-out period of at least 6 days between each regimen. Twelve hours after consumption of cranberry or placebo hard capsules, the first urine of the morning was collected. Different Escherichia coli strains were cultured in the urine samples. Urinary antibacterial adhesion activity was measured in vitro using the human T24 epithelial cell-line, and in vivo using the Caenorhabditis elegans killing model. With the in-vitro model, 108 mg of cranberry induced a significant reduction in bacterial adherence to T24 cells as compared with placebo (p 0.001). A significant dose-dependent decrease in bacterial adherence in vitro was noted after the consumption of 108 and 36 mg of cranberry (p 0.001). The in-vivo model confirmed that E. coli strains had a reduced ability to kill C. elegans after growth in the urine of patients who consumed cranberry capsules. Overall, these in-vivo and in-vitro studies suggested that consumption of cranberry juice represents an interesting new strategy to prevent recurrent urinary tract infection.

OBJECTIVE: To determine whether Methenamine Hippurate (MH) or cranberry tablets prevent urinary tract infections (UTI) in people with neuropathic bladder following spinal cord injury (SCI).

STUDY DESIGN: Double-blind factorial-design randomized controlled trial (RCT) with 2 year recruitment period from November 2000 and 6 month follow-up.

SETTING: In total, 543 eligible predominantly community dwelling patients were invited to participate in the study, of whom 305 (56%) agreed.

METHODS: Eligible participants were people with SCI with neurogenic bladder and stable bladder management. All regimens were indistinguishable in appearance and taste. The dose of MH used was 1 g twice-daily. The dose of cranberry used was 800 mg twice-daily. The main outcome measure was the time to occurrence of a symptomatic UTI.

RESULTS: Multivariate analysis revealed that patients randomized to MH did not have a significantly longer UTI-free period compared to placebo (HR 0.96, 95% CI: 0.68-1.35, P=0.75). Patients randomized to cranberry likewise did not have significantly longer UTI-free period compared to placebo (HR 0.93, 95% CI: 0.67-1.31, P=0.70).

CONCLUSION: There is no benefit in the prevention of UTI from the addition of MH or cranberry tablets to the usual regimen of patients with neuropathic bladder following SCI.

PURPOSE: To determine, from a societal perspective, the effectiveness and cost effectiveness of concentrated cranberry tablets, versus cranberry juice, versus placebo used as prophylaxis against lower urinary tract infection (UTI) in adult women.MATERIALS AND METHODS: One hundred fifty sexually active women aged 21 through 72 years were randomized for one year to one of three groups of prophylaxis: placebo juice + placebo tablets versus placebo juice + cranberry tablets, versus cranberry juice + placebo tablets. Tablets were taken twice daily, juice 250 ml three times daily. Outcome measures were: (1) a >50% decrease in symptomatic UTI's per year (symptoms + >or= 100 000 single organisms/ml) and (2) a >50% decrease in annual antibiotic consumption. Cost effectiveness was calculated as dollar cost per urinary tract infection prevented. Stochastic tree decision analytic modeling was used to identify specific clinical scenarios for cost savings.RESULTS: Both cranberry juice and cranberry tablets statistically significantly decreased the number of patients experiencing at least 1 symptomatic UTI/year (to 20% and 18% respectively) compared with placebo (to 32%) (p0.05). The mean annual cost of prophylaxis was $624 and $1400 for cranberry tablets and juice respectively. Cost savings were greatest when patients experienced >2 symptomatic UTI's per year (assuming 3 days antibiotic coverage) and had >2 days of missed work or required protective undergarments for urgency incontinence. Total antibiotic consumption was less annually in both treatment groups compared with placebo. Cost effectiveness ratios demonstrated cranberry tablets were twice as cost effective as organic juice for prevention.CONCLUSIONS: Cranberry tablets provided the most cost-effective prevention for UTI.

No abstract - Purpose: The aim of our correspondence is to submit the results of a small study (the first in a Greek population to our knowledge) about administering cranberries in the form of capsules to healthy postmenopausal women with recurrent UTIs.

OBJECTIVE: To determine the effectiveness of cranberry supplement at preventing urinary tract infections (UTIs) in persons with spinal cord injury (SCI).

DESIGN: A prospective, double-blinded, placebo-controlled, crossover study.

PARTICIPANTS: 21 individuals with neurogenic bladders secondary to SCI.

MAIN OUTCOME MEASURES: Favorable or unfavorable response of cranberry supplement vs placebo on urinary bacterial counts and white blood cell (WBC) counts and the combination of bacterial and WBC counts.

METHODS: Individuals with neurogenic bladders due to SCI were recruited and randomly assigned to standardized 400-mg cranberry tablets or placebo 3 times a day for 4 weeks. After 4 weeks and an additional 1-week ""washout period,"" participants were crossed over to the other group. Participants were seen weekly, during which a urine analysis was obtained. UTI was defined as significant bacterial or yeast colony counts in the urine and elevated WBC counts (WBC count > or = 10 per high power field) in centrifuged urine. Participants with symptomatic infections were treated with appropriate antibiotics for 7 days and restarted on the cranberry tablet/ placebo after a 7-day washout period. Urinary pH between the cranberry and placebo groups was compared weekly. Data were analyzed using the Ezzet and Whitehead's random effect approach.

RESULTS: There was no statistically significant treatment (favorable) effect for cranberry supplement beyond placebo when evaluating the 2 treatment groups for bacterial count, WBC count, or WBC and bacterial counts in combination. Urinary pH did not differ between the placebo and cranberry groups.

CONCLUSION: Cranberry tablets were not found to be effective at changing urinary pH or reducing bacterial counts, urinary WBC counts, or UTIs in individuals with neurogenic bladders. Further long-term studies evaluating specific types of bladder management and UTIs will help to determine whether there is any role for the use of cranberries in individuals with neurogenic bladders.