“Cran”tibiotics

A glass of cranberry juice a day keeps the doctor away? This may be the case, according to a recent study of women with urinary tract infections (UTIs) conducted by researchers at the University of Oulu, Finland.

As many as 60% of women will suffer the frequency, urgency, dysuria, fevers, pain, and general annoyance of a UTI in their lifetime. And at least one-third of those women will be afflicted with recurrences within a year. The culprit—coliform bacteria, most commonly E. coli, a regular inhabitant of human stool—can be displaced during sexual intercourse and prey upon the cells lining the urinary tract (uroepithelia). The bacteria can then colonize and cause an infection. Antimicrobial therapy is the current treatment and prophylactic; but alternate therapies are being explored. Intravaginal administration of lactobacillus, a probiotic bacterium, has been shown to be effective in the prevention of UTIs. A more easily accessible and inexpensive option is cranberry juice. Cranberries contain proanthocyanidins, which inhibit the cellular expression of adhesive components in bacterial cells. The inability to adhere to uroepithelia prevents bacterial colonization and subsequent infection in women.

Researchers conducted an open, randomized, controlled study involving 150 female students and staff at the health center at Oulu University testing the effectiveness of cranberry juice and oral lactobacillus juice in the prevention of UTIs. The women, who all had a history of UTIs, were diagnosed and treated with antibiotics, and then were either given 50 mL of cranberry– lingonberry juice concentrate every day for 6 months, 100 mL of oral lactobacillus 5 times a week for 12 months, or were in the control group. The cranberry trial was cut short because the manufacturer of the cranberry juice had stopped production. After six months, the recurrence of UTIs in the cranberry group was 16%, compared with 39% in the lactobacillus group and 36% in the control group. At 12 months, the results were similar, with 24%, 42%, and 38% recurrence, respectively.

The study showed that cranberry juice is effective in the prevention of recurrent UTIs, whereas oral lactobacillus, at the given dosage, is not. Although participants drank cranberry juice for only 6 months, they still had almost half the level of recurrence at 12 months.

More than 11 million women in the United States are treated with antibiotics for UTIs in a year, at a cost of $1.6 billion. With the expense and the increasing resistance of the bacteria to antimicrobial therapy, the results of this study are promising for women who must repeatedly deal with the unpleasant infections. Now, they may find relief by simply adding a glass of cranberry juice to their daily routine.