Probiotics for the prevention of cystitis

On Monday I briefly mentioned the usefulness of probiotics (‘friendly bacteria’) in restoring the bacteria of the digestive system for women who have taken repeated courses of antibiotics for their cystitis or other urinary tract infections (UTI’s).  However, probiotics may do more than just help positively rebalance gut bacteria after antibiotic use.  Studies indicate that oral probiotic supplements and vaginal probiotic creams and suppositories may actually help prevent and treat the occurrence of UTIs.

You may be wondering how probiotics (taken orally or used vaginally) could be helpful in treating or preventing infections in the urinary system?  As I mentioned on Monday, in women the bacteria responsible for urinary tract infections almost always come from the vagina or the rectum/anus and travel up through the urinary tract into the bladder where they can cause problems.  In a healthy vagina the predominant bacteria present are ‘friendly’ non-harmful strains such as Lactobacilli (1), a healthy digestive system will also be dominated by a variety of different non-pathogenic bacteria.  If the vagina and digestive system are mainly colonised with good bacteria these provide a barrier to the entry of pathogenic/harmful bacteria into the urinary tract and bladder (1).  Studies now show that probiotic supplements or foods may be helpful in order to boost the number of good bacteria in the vagina and digestive system and therefore help to prevent urinary tract infections.  Evidence also suggests that probiotics may also actively prevent the pathogenic bacteria from clinging or adhering to the urinary tract and multiplying (2).

One study (3) analysed the diet of over a hundred women, with an average age of 30, who suffered from recurrent UTI’s compared to over a hundred women who had not suffered from a UTI in over 5 years.  Frequent consumption, more than three times a week, of milk products containing probiotics was associated with a significantly reduced risk of recurrent UTI’s.  Studies (4,5) also indicate that vaginal suppositories of probiotic bacteria may be useful for the prevention of recurrent urinary tract infections.

Urine normally flows in one direction, down from the kidneys, through tubes called ureters, to the bladder.  However there is a condition known as vesicoureteral reflux (VUR) where there is an abnormal flow of urine from the bladder back into the ureters.  It is a condition most commonly diagnosed in childhood after a urinary tract infection has occurred. About one-third of children with a UTI are found to have VUR. VUR can lead to infection because urine that remains in the urinary tract provides a place for bacteria to grow.  A study(6) in children with VUR compared the preventative effect of oral probiotics with antibiotics.  The probiotic was shown to be as effective as the antibiotic in the prevention of recurrent UTIs.

The evidence for the use of probiotic supplements and vaginal suppositories in the treatment and prevention of UTI in women is still preliminary but ever growing.  There is a lot of logic behind the rationale and in practice many women, especially those who have undergone repeat antibiotic treatment, find probiotics to be really helpful in preventing and treating cystitis and other urinary tract infections.  Vaginal probiotic creams, suppositories and tablets are readily available, they usually contain lactobacillus acidophilus.  Oral probiotics (and prebiotics) may be useful in order to help keep an overall balance of good bacteria in the vagina and digestive and system.

(1) Reid G & Bruce AW.  2006.  Probiotics to prevent urinary tract infections: the rationale and evidence.  World J Urol.  24:28-32
(2) Reid G.  2000.  Probiotic Therapy and Functional Foods for Prevention of Urinary Tract Infections: State of the Art and Science.  Curr Infect Dis Rep.  2:518-522
(3)Kontiokari T et al.  2003.  Dietary factors protecting women from urinary tract infection.  Am J Clin Nutr.  77:600-604
(4) Uehara S et al.  2006.  A pilot study evaluating the safety and effectiveness of Lactobacillus vaginal suppositories in patients with recurrent urinary tract infection.  Int J Antimicrob Agents.  28 Suppl 1:S30-S34
(5) Czaja CA et al.  2007.  Phase I trial of a Lactobacillus crispatus vaginal suppository for prevention of recurrent urinary tract infection in women.  Infect Dis Obstet Gynecol.  2007:35387
(6) Lee SJ et al.  2007.  Probiotics prophylaxis in children with persistent primary vesicoureteral reflux.  Pediatr Nephrol.  22:1315-1320

Written by Ani Kowal