Effect of Cranberry Pills on Bacteruria and Pyruria in Persons with Neurogenic Bladder Secondary to SCI [Archive]

Wise Young

10-22-2001, 10:55 AM

Effect of Cranberry Pills on Bacteriuria and Pyuria in Persons with Neurogenic Bladder Secondary to SCI

Rationale
Although renal failure is no longer the leading cause of death following spinal cord injury (SCI), urinary tract infections (UTI) are extremely common lifelong secondary complications in this population, still posing a threat to survival and quality of life

Concern about overuse of systemic antimicrobial agents in persons with SCI, both for treatment of asymptomatic bacteriuria and for prophylaxis, has prompted study of consumer-directed alternative approaches and recommendations for reducing antimicrobial use (1). A potential approach for preventing UTI in persons with SCI is to modify the local environment in the bladder biochemically through inhibition of bacterial attachment or acidification of the urine.

The use of cranberry juice has been touted for many years as a potential therapeutic and/or prophylactic alternative in various populations prone to develop UTI. The 1992 National Institute for Disability and Rehabilitation Research (NIDRR) Consensus Conference Report (1) stated that while prophylaxis with cranberry juice or ascorbic acid is commonly used, there are no published studies showing beneficial effects in the SCI population. Recent studies demonstating efficacy of cranberry juice in reduction of bacteriuria and pyuria in elderly women (2), and availability of cranberry juice in tablet form makes this a potentially exciting subject for study in the SCI population.

Specific Objectives
The overall goal of this study will be to determine whether antibacterial effects of cranberries can be used to reduce bacteriuria, pyuria, and ultimately symptomatic UTI in outpatients with SCI. Specific objectives are to:

1. Determine whether daily dietary supplement of cranberry extract capsules reduce or eliminate bacteriuria and pyuria in community-residing outpatients with neurogenic bladder secondary to SCI who have positive baseline urine cultures; and 2. Determine whether daily dietary supplement of cranberry extract capsules prevents or delays emergence of bacteriuria and pyuria among community-residing persons with neurogenic bladder secondary to SCI who have negative baseline urine cultures.

Project Design/Methodology
A randomized double-blind placebo-controlled trial in which community-residing persons with SCI will ingest 2000 mg of cranberry concentrate in capsule form or placebo daily for 6 months will be conducted. Randomization will be stratified based on initial culture result (positive or negative). Urine will be examined monthly for presence of bacteriuria and pyuria. The study sample will be drawn from the entire UAB SCI Outpatient Clinic population of over 1100 persons.

This is an especially attractive proposal in that it is a community-based, consumer-directed program, utilizing an agent with no known toxicity or side effects, that does not alter normal bacterial flora, does not require use of antimicrobials or medical supervision, and importantly, has low cost. It allows shared decision-making between the consumer and the physician for management of UTI.

Anticipated Research Results
Bacteriuria and UTI in the setting of neurogenic bladder secondary to SCI makes it difficult to predict how well subjects in our proposed studies will respond in the microbiological sense to daily dietary supplements of cranberry juice in tablet form. A single controlled study in asymptomatic elderly women with bacteriuria showed that ingestion of 300 ml of cranberry juice cocktail daily for 6 months not only reduced the likelihood of non-bacteriuric women from becoming bacteriuric, but also demonstrated an apparent effect of reducing the occurrence of bacteriuria among women previously shown to be bacteriuric.

Bacterial colonization of the lower genitourinary tract in persons with SCI may be more deep-seated and resistant to the effects of substances in cranberries that apparently act to prevent bacterial attachment to uroepithelial cells. Nonetheless, we are sufficiently encouraged by the findings of Avorn et al (2) to anticipate a reduction in the rate of bacteriuria and pyuria among persons with SCI, possibly 20-30% or more. Given 75% of asymptomatic persons free of indwelling catheters have positive urine cultures at the time of their annual urologic examinations (3), such a reduction could be of great significance in reducing the need for antimicrobials and other medical expenses for treatment of symptomatic UTIs that occur approximately twice yearly in this population (4).

References

1. National Institute for Disability and Rehabilitation Research. 1992. The prevention and management of urinary tract infections in persons with spinal cord injuries - NIDRR Consensus Statement. J Am Paraplegic Soc 15:194-207. 2. Avorn, J. 1996. The effect of cranberry juice on the presence of bacteria and white blood cells in the urine of elderly women. What is the role of bacterial adhesion? Adv Exp Med Biol 408:185-186. 3. Stover, S.L., L.K. Lloyd, K.B. Waites, et al. 1989. Urinary tract infection in spinal cord injury. Arch Phys Med Rehabil 70:47-53. 4. Waites, K.B., K.C. Canupp, M.J. DeVivo. 1998 Development and application of an electronic spinal cord injury infection and antimicrobial resistance database. Abstracts of American Spinal Cord Injury Association, J Spinal Cord Med, in press.

Ken B. Waites, MD
Primary Investigator

<http://main.uab.edu/images/dot_clear.gif> [ ]
<http://main.uab.edu/images/dot_clear.gif> Grant: Rehabilitation Research and Training Center on Secondary Conditions of Spinal Cord Injury Principal Investigator: Amie B Jackson, MD Funding Source: National Institute on Disability and Rehabilitation Research Term of Grant: Oct 1, 1998 - Sept 30, 2003