- Stay a step ahead of urinary tract infections
- How it starts
- Symptoms and risks
- Diagnosis and treatment
- What you should do
- Myths and Truths About Urinary Tract Infections
- MYTH: Hygiene habits, and fashion choices, contribute to UTIs
- TRUTH: Female gender is the biggest risk factor for a UTIs
- SOME MYTH, SOME TRUTH: Sexual Activity
- TRUTH: Type of UTI Test Matters, Especially for Frequent Infections
- MYTH: Long Course of Antibiotics is Better Than Short
- SOME MYTH, SOME TRUTH: Prevention Strategies
- Urinary Tract Infections in Women
- What Exactly is a Urinary Tract Infection?
- The Signs and Symptoms of a Urinary Tract Infection
- The Risk Factors for Developing a Urinary Tract Infection
- Understanding Your UTI Treatment Options Using Diet and Probiotics
- Expert Review of Anti-infective Therapy
- 1. Introduction
Stay a step ahead of urinary tract infections
Drink plenty of fluids to help flush out bacteria in the urinary tract. Drink enough each day so that your urine is almost clear in color.
Published: February, 2015
Keep hydrated, and empty your bladder often to stave off these risky infections.
Urinary tract infections (UTIs) are among the most common infections in older adults, especially in women. But the infections are also commonly overdiagnosed and overtreated. “The overuse of antibiotics to treat urinary tract infections is a problem,” says Dr. Michael O’Leary, a urologist at Harvard-affiliated Brigham and Women’s Hospital.
How it starts
The urinary system is made up of the kidneys, which filter toxins and extra water out of blood to create urine; the ureters, which send urine to the bladder; and the urethra, through which urine is excreted.
UTIs often result when urine pools in the bladder, making it a perfect spot for bacteria to grow. Pooling may be caused by an obstructed urinary flow—from an enlarged prostate in a man or a descended bladder in a woman. Or a UTI may happen if “bad” bacteria cling to the urethra and find their way to the bladder. Other causes include sexual activity, catheters, kidney stones, and a lack of estrogen in the lining of a woman’s vagina (estrogen helps protect against UTIs).
Symptoms and risks
UTI symptoms include frequent urination, a sense of urgency to urinate, and a burning feeling that occurs with urination. In older adults, confusion is also a common clue that may go unnoticed or chalked up to mild dementia. “Older men usually get obvious symptoms, but sometimes the only symptom for older women may be confusion,” says Dr. O’Leary.
If a UTI is untreated, it may spread to the kidneys, where the bacteria can get into the bloodstream easily. This can lead to sepsis, the body’s toxic and sometimes deadly response to infection.
Diagnosis and treatment
Diagnosing a UTI requires testing a sample of urine to look for bacteria and white blood cells, indicating the presence of infection. If a test turns out positive, it’s necessary to grow the bacteria in a lab to see which type is causing infection. Treatment is usually a short course of antibiotics, but a more advanced infection may require stronger antibiotics given in a hospital.
Dr. O’Leary says this process is where many doctors overdiagnose a UTI. “Older women have bacteria and white blood cells in their urine. But if the person doesn’t have symptoms, it’s not a UTI, and the person is needlessly treated with antibiotics. That’s how you get resistant organisms.”
What you should do
Call your doctor at the first sign of symptoms. The sooner you can catch a UTI, the better. And do try to prevent UTIs by staying hydrated. “Don’t worry about trying to drink eight 12-ounce glasses of water a day,” says Dr. O’Leary, “but do drink plenty of fluids, since urinating helps to flush out bacteria.” A general rule is to drink enough so that your urine is almost clear in color. Other suggestions include emptying the bladder throughout the day, emptying the bladder after sex, and—for women—a vaginal estrogen cream.
Can diet lower your UTI risk?
A urinary tract infection (UTI) may not be completely avoidable. But some dietary choices may ward off UTIs.
Cranberries: These may help prevent (but not treat) UTIs by keeping bacteria from sticking to the lining of the urinary tract. Add cranberries to salads or brown rice; use cranberry extracts, which are low in sugar; or drink unsweetened cranberry juice.
Blueberries: Like cranberries, blueberries may also keep bacteria from attaching to the urinary tract lining. Try them in salads, stir them into smoothies, add them to plain Greek yogurt.
Vitamin C: “This can help make the urine more acidic, which may prevent bacteria from growing,” says geriatrician Dr. Suzanne Salamon, an instructor at Harvard Medical School. She recommends taking a supplement of 500 to 1,000 milligrams of vitamin C daily, or getting vitamin C from foods, such as oranges, lemons, grapefruits, strawberries, blueberries, green leafy vegetables, and green peppers.
Probiotics: These products contain colonies of “good” bacteria. Some evidence suggests that probiotics may help prevent UTIs by keeping “bad” bacteria from growing in the vagina. Probiotics are available in supplements and in fermented foods such as plain Greek yogurt, cheese, and a drink called kefir.
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Myths and Truths About Urinary Tract Infections
Urinary Tract Infection (UTI) is one of the most common infections in women – second only to intestinal bugs.
A UTI can occur anywhere along the urinary tract, including in the kidneys and along the tubes (ureters) that connect the kidneys to the bladder. More commonly, though, infections involve the lower urinary tract: the bladder (where urine is stored) and in the urethra tube that empties urine to the outside.
For physicians, treatment involves a delicate balance of relieving symptoms, clearing the infection, and minimizing adverse effects by choosing the right antibiotic for the optimal duration.
For patients, the first question is when to see a doctor after feeling the initial symptoms. Typically, these symptoms are burning pain with urination, urgency and frequency of urination, and pain above the pubic bone.
“Our bodies sometimes can clear these infections on their own,” says Elodi Joy Dielubanza, MD, a urologist in Brigham and Women’s Hospital’s Division of Urology, who has additional training in female pelvic medicine and reconstructive surgery.
But if symptoms do not abate within a couple of days, contact a doctor. Antibiotics may relieve symptoms shortly after you begin taking them.
An immediate visit to a physician is warranted if you have accompanying fever, flank pain, flu-like symptoms, or four-smelling vaginal discharge, she notes. These may be signs that your body may be fighting more than an uncomplicated UTI. Contrary to a common assumption among patients, the smell or appearance of urine by itself is not a reliable measure of infection, says Dr. Dielubanza.
Here she addresses some other common myths, and truths, about UTIs.
MYTH: Hygiene habits, and fashion choices, contribute to UTIs
You may have heard that certain hygiene practices are risk factors for UTIs, particularly for women. But UTIs are not caused by how you wipe in the bathroom, by tampon use, or by failing to empty your bladder after sexual intercourse, Dr. Dielubanza says.
“A lot of women express concern about these,” says Dr. Dielubanza. “But studies have shown there is no association between these practices and UTIs.” Fashion also is not to blame: Tight clothes, she says, do not cause UTIs.
TRUTH: Female gender is the biggest risk factor for a UTIs
Being female, however, does increase the risk, for simple reasons of anatomy. UTIs generally are caused by bacteria that live in the colon, especially the rectum. The short length of the female urethra places its opening close to bacterial reservoirs (the anus and vagina) making women more vulnerable to infection.
“In truth, female gender is simply the strongest risk factor for UTIs,” says Dr. Dielubanza.
Another trigger particular to women is hormonal fluctuation with age. Until menopause, vaginal flora (microbes that normally live in the vagina) includes protective bacteria. But when estrogen drops during menopause, the pH of the vagina changes, and the good flora cannot thrive there as easily. Without these good bacteria, the “bad” bacteria can more easily flourish in postmenopausal women.
Men are not immune to UTIs, but they are less susceptible. This is because their longer urethras present a challenge to bacterial ascent. However, as men age and begin to empty their bladders less efficiently due to prostate enlargement, urinary tract infections can become more common.
A trigger for UTIs in both men and women is use of any medical instrument near the urethra, including catheterization to drain urine.
SOME MYTH, SOME TRUTH: Sexual Activity
Sexual intercourse (or intercourse-like activity) indeed can be a strong trigger for a UTI, as can any activity that has the potential for putting infection-causing bacteria in proximity of the urethra.
“Your partner’s anatomy can act as a ladder for infection of the urethra with bacteria that usually live in the bowel,” says Dielubanza.
Use of spermicides with or without barrier contraceptives has been shown to increase the risk of urinary tract infections in sexually active women. Women may consider an alternative contraceptive regimen if they experience UTIs after intercourse.
TRUTH: Type of UTI Test Matters, Especially for Frequent Infections
For patients with recurrent urinary tract infection (three or more infections within 12 months or more than two infections within 6 months), your physician likely will culture your urine to determine the specific type of bacteria causing your infection. A culture is more informative than a dipstick urine test that reveals only whether an infection is likely to be present.
The right test is particularly important for someone who experiences recurring infections. “This is to be sure that your symptoms truly are due to infection and that the antibiotics usually used for these infections are appropriate for you,” says Dr. Dielubanza.
MYTH: Long Course of Antibiotics is Better Than Short
Typically, antibiotics are prescribed for three to five days for symptoms confined to the lower urinary tract in patients who have no fever, flank pain, or flu-like symptoms.
“Longer courses do not increase the likelihood of clearing the infection,” says Dr. Dielubanza. “But they do increase the risk of antibiotic resistance, increase the risk of yeast infections, and increase the risk of infectious forms of diarrhea.”
A longer course may be required for someone who has more severe symptoms of an infection or if the infection is in the bladder. Always follow all instructions and take antibiotics for the number of days prescribed.
SOME MYTH, SOME TRUTH: Prevention Strategies
You may hear or read about prevention strategies for UTI, with cranberry supplements among the most popular. But there is not hearty scientific evidence to support the use of cranberry juice or supplements to prevent UTI. Data thus far have shown no benefit or been inconclusive.
The body’s best defense against urinary bacteria is adequate urine flow to wash away bacteria. Maintaining adequate hydration and avoiding urine holding are good strategies for prevention.
Increasingly, doctors are advocating probiotics via diet (yogurt, kefir, fermented foods) or supplements. While there is no evidence that probiotics alone offer sufficient protection against UTIs, they can be effective when used along with other prevention strategies by promoting healthy vaginal and bowel flora.
Women who experience recurrent UTIs can discuss with a doctor possible medical prevention strategies, such as low dose antibiotics and vaginal estrogen replacement after menopause.
Urinary Tract Infections in Women
Most women will experience more than one urinary tract infection — also known as UTIs — over their lifetime. The “honeymoon cystitis” our mothers were told about speaks to one of the primary causes of the urinary tract infection—the milking action of sexual activity, which can cause bacteria from the vaginal or anal area to get into the bladder and urethra. Neglecting treatment of a UTI can be dangerous because the infection can ascend into the kidneys. If you think you may have a UTI, have a urine culture taken. If it is positive for bacteria, your doctor will prescribe an antibiotic that will usually cure the problem without further treatment.
Recurrent bladder infections, however, require a different approach. Chronic use of antibiotics to treat recurrent UTIs doesn’t address the underlying imbalance in the body that is leading to the infections. Antibiotics can also kill off helpful vaginal flora, resulting in yeast infections, diarrhea, and—unfortunately—recurrent urinary tract infection.
Urinary Tract Infection Symptoms
The symptoms of urinary tract infections include burning on urination, blood in the urine, and fever.
Causes of Urinary Tract Infection
Women with episodic urinary symptoms often find that the episodes are accompanied by anger or feeling “pissed off.” Developing a urinary tract infection may be the body’s way of releasing anger. Pay attention to what happened in your life and relationships 24 to 48 hours before the onset of the symptoms. When the anger becomes more chronic and less available on a conscious level, the symptoms may take the form of continual urinary urgency and frequency.
Studies have shown that women with chronic bladder infections have more free-floating anxiety and more obsessive personality traits and tend to experience emotions only through their bodily symptoms (somatoform disorder) compared to women without this problem. Several researchers have found that women who feel the need to urinate frequently but who don’t have infections are more anxious and neurotic than those without the problem. Similarly, women who are anxious also experience urinary urgency (feeling as if you can’t make it to the bathroom in time), needing to get up at night to urinate, and frequent urination.
Healing Alternatives for UTIs
Get a medical evaluation to be sure that you don’t have some anatomical problem that is contributing to your infections. Make sure that the outer third of your urethra is well estrogenized. Your doctor should be able to evaluate this during a pelvic exam, because the urethra runs right under the top part of the vagina and is easily felt and observed. If there is any evidence of thinning of the outer urethra, which is common in menopausal and perimenopausal women, get a prescription for estrogen cream and use it in the upper part of the vagina, right along the urethral ridge. I recommend estriol 0.5 mg vaginal cream. The usual dose is 1 gram (one-quarter teaspoon) once daily for one week, then twice or three times per week or as needed thereafter. Other forms of vaginal estrogen also work well, including Estrace and Vagifem. The small amount needed to re-estrogenize the urethra does not raise levels in the blood significantly and is considered safe. Iosif1
Spiritual and Holistic Options for Urinary Tract Infections
- Stop all caffeine, even decaf, for two weeks because caffeine is a bladder irritant. Reintroduce to see if symptoms recur.
- Drink lots of water or unsweetened (or artificially sweetened) cranberry juice the minute you feel any bladder symptoms. The extra liquid helps flush out bacteria, and cranberry juice also acidifies the urine, making it harder for bacteria to grow. Drink 16 oz. per day to treat an infection, or 8 oz. per day to prevent infections.
- Try cranberry capsules available at natural food stores. Cranberries contain a substance that prevents bacteria from sticking to the bladder wall, thus decreasing the risk for recurrent infection.
- Take a probiotic regularly to help recolonize your gut with “friendly” bacteria. Because the anus and urethra are so close anatomically, encouraging the growth of favorable bacteria in one area of the body also helps the other. My favorite probiotic is PB 8, which unlike most other probiotics doesn’t have to be refrigerated.
- Another way to help restore your vaginal flora if you’ve had repeated UTIs and multiple courses of antibiotics is to dip a stiff tampon (such as OB) in plain organic yogurt and put it in your vagina. Change “yogurt tampons” every three or four hours. You can also douche with yogurt or put a probiotic capsule directly in your vagina each night for a few nights.
- Acupuncture and Chinese herbs work very well for recurrent UTIs.
- The herb uva ursi contains a natural antibiotic that relieves bladder infection. The powdered solid extract (20 percent arbutin) comes in capsules; take two three times per day. You can also take the tincture—one dropperful in a cup of water three times per day.
- Vitamin C helps prevent reinfection. Take 1,000 to 2,000 mg every day, and if your infections are associated with sexual activity, take 1,000 mg before and 1,000 mg after sex. Drink plenty of fluids, and be sure to urinate within one hour of having sex.
- UTIs are often associated with frequent or traumatic sex (sex that involves injury to the vaginal and vulvar tissues). Treatment involves making the necessary adjustments in your sex life to decrease trauma. This may mean using a lubricant if you suffer from vaginal dryness. It may also mean rethinking any aspects of the relationship that are less than satisfactory.
- Repeated bouts of infection and/or burning on urination can also be related to a woman’s contraceptive method. If your diaphragm is too large, it can irritate your urethra during intercourse, causing bacteria to enter the urethral opening and migrate up to the bladder area. Also, the use of condoms or contraceptive creams that contain the spermicide nonoxynol-9 can cause urethral irritation and burning on urination. It will go away when you stop using the offending agent.
- Don’t introduce bacteria into your urethral area. After using the toilet, make sure you wipe yourself from front to back, not the other way around.
- Castor oil packs applied to your lower abdomen two or three times a week can work wonders in preventing UTIs because they appear to improve immune system functioning.
Learn More — Additional Resources
- Women’s Bodies, Women’s Wisdom, by Christiane Northrup, M.D., Chapter 9
Last Updated: October 9, 2006
Millions of people in the United States suffer from the side effects of urinary tract infections every year—and if you’re one of these millions, you know that the experience is far from pleasant. What’s worse, a UTI can actually be quite dangerous if not effectively treated, leading to recurrent UTI’s, permanent kidney damage, and even life-threatening sepsis.
Luckily, there are steps that you can take to identify the causes of your urinary tract infections, aid them and support urinary tract health—and it may be as simple as adding a daily probiotic supplement to your diet.
What Exactly is a Urinary Tract Infection?
Before we look at why probiotic therapy can be so effective at clearing up even recurrent urinary tract infections, let’s take a look at what exactly is going on in your body when you’re in the middle of a UTI. In essence, a urinary tract infection (or UTI) is an infection that arises in any part of the urinary system, including the kidneys, ureters, urethra, and bladder. Most infections are located in the lower part of the urinary tract where the bladder and urethra live.
The majority of UTIs are bacterial infections. The specific type of bacteria and its sources can vary. Infections located in the bladder are often caused by Escherichia coli bacteria (also known as E. coli), a bacterial strain that is often found in the digestive tract. On the other hand, urinary tract infections of the urethra are more commonly caused by harmful bacteria strains from your gastrointestinal tract that have been spread from your anus to your urethra. About four-fifths of all urinary tract infections are caused by two types of bad bacteria: E. coli and Staphylococcus saprophyticus. (1)
Urinary tract infections can also be caused by fungi and viruses, including sexually transmitted infections such as gonorrhea, herpes, chlamydia, and mycoplasma.
The Signs and Symptoms of a Urinary Tract Infection
Unsurprisingly, many of the most obvious and common symptoms of a urinary tract infection can be found by looking at your urine. Dark or cloudy urine, urine that is red or bright pink, or strong-smelling urine are all clear signs of a UTI. Similarly, feeling a constant and strong need to urinate, having a burning or sharp sensation when you urinate, or feeling like you can’t fully empty your bladder can signal an infection. While UTIs aren’t always painful, pelvic pain—specifically for women—is often associated with urinary tract infection. (2)
The Risk Factors for Developing a Urinary Tract Infection
While anyone can develop a urinary tract infection, certain risk factors can increase your chances of getting a UTI—and the biggest risk factor may be your gender. Women are far more prone to developing a urinary tract infection than men are. Indeed, clinical studies show that about half of women experience at least one UTI during their lifetime. (3) There are several reasons for this. First, the female urethra is shorter than that of men, allowing bacteria to get to and infect the bladder more easily. The proximity of a woman’s urethra opening to the rectum also increases the risk for a UTI. (2)
The use of certain birth control methods (such as spermicide or diaphragms) also increases a woman’s risk of developing a UTI, as does wiping from back to front after using the restroom. (2) The risk of contracting a UTI notably increases during pregnancy, particularly in weeks six through 24. It’s thought that the increased weight and size of the uterus interferes with the ability to completely void the bladder, making UTIs more common. (4) Postmenopausal women are at increased risk due to hormone changes that affect beneficial bacteria populations. (2)
Beyond gender-related risk factors, several other health conditions can boost the chances of getting a UTI for both men and women. Having a condition that affects immune response (like diabetes) can increase UTI risk, as can any injury to the spinal cord or the nerves around the bladder. Use of a urinary catheter can make it easier for harmful bacteria to enter the urethra/urogenital tract and cause an infection. An enlarged prostate or kidney stones can block urine flow and promote bacteria growth as well. (2) There’s also some evidence that genetics may play a role in your susceptibility to recurrent urinary tract infection. (5)
Understanding Your UTI Treatment Options Using Diet and Probiotics
If you’ve gone to the doctor about a urinary tract infection in the past, chances are that you’ve been prescribed an antibiotic for treatment. Unfortunately, numerous clinical studies have shown that antibiotic use can result in a host of negative health side effects, including decimating the good bacteria populations of your gut and interrupting the normal flora balance in your digestive tract. (6)
But don’t worry: there are a number of natural, healthy things you can do to avoid a urinary tract infection and prevent repeat incidence of UTIs without destroying the delicate balance of your gut microbiome.
Common wisdom holds that you should get at least eight glass of water a day, but it’s easy to ignore your thirst as you go through your busy day. If you suffer from recurrent UTI, however, this is a bad move. Staying hydrated is one of the most effective ways to reduce the recurrence of UTI. Why? In short, drinking more fluids leads you to pee more—and this is key to ensuring that the bad bacteria that cause urinary tract infections are flushed out of your urinary tract.
The importance of drinking plenty of fluids for the prevention of UTI has been demonstrated in several clinical studies. In one, researchers found that infrequent urination caused by low fluid intake was directly related to urinary tract infection recurrence. (7) Another research study showed the corollary: that increasing fluid intake was related to a decrease in the frequency of UTIs. (8)
Does it matter what you drink to stay hydrated? Water is certainly a reliable way to get enough liquids, but if you want a little variety, try unsweetened cranberry juice. Unsweetened cranberry juice is one of the best-known natural urinary tract infection remedies, and for good reason: cranberry consumption helps prevent harmful bacteria from adhering in the urinary tract, decreasing the chance of infection. (9) One double-blind study looked at women who had a history of urinary tract infections. Half were asked to drink eight ounces of cranberry juice daily. Those who drank the unsweetened cranberry juice ended up experiencing fewer UTIs than those in the control group. (10)
LoveBug’s Yeast is a Beast daily probiotic supplement has all the health benefits of cranberry juice, without the added sugar. That’s thanks to the addition of Cran-Gyn (cranberry extract) and D-mannose in each tablet.
Get more Vitamin C
Vitamin C is well-known for playing a key role in boosting your immune system during the cold season, but it has an important role to play in decreasing urinary tract infection, too. How? Scientists think that vitamin C increases urine acidity, and this increase in acidity helps kill the bad bacteria that lead to infection. (11) One clinical study of pregnant women found that those who took 100mg of vitamin C daily had fewer than half as many UTIs as those in the control group. (12) Even better, getting enough vitamin C in your diet is easy (and delicious!): oranges, kiwi, grapefruit and red peppers all have the total recommended value of the vitamin in a single serving.
Practice Healthy Hygiene Habits
Simple, everyday hygiene habits can also help in the prevention of recurrent urinary tract infection. Studies have found that peeing after sex can reduce the spread of bacteria and lower your chance for infection, as can avoiding the use of spermicide. (13) (14) Always make sure to wipe front to back after using the restroom. (15) Perhaps most importantly, stop holding it! Research shows that holding in urine for too long can cause bacteria to build up and cause an infection. (16)
Take a Probiotics for UTI Treatment/Prevention
If you’re going to take just one daily supplement, make it a probiotic. The use of probiotics has been shown to be effective in everything from improving digestive health to supporting immune function—and certain probiotic strains have been shown to be effective in supporting urinary tract health. One research study found that supplementing with Lactobacillus probiotics reduced the risk of UTIs in women. (17) In another clinical study, probiotics were shown to boost treatment effectiveness when combined with antibiotics compared to the antibiotic alone.
Taking a probiotic supplement aimed specifically at addressing women’s health issues can increase the effectiveness of probiotics in supporting urinary tract health even further. LoveBug’s Yeast is a Beast daily probiotic supplement is specifically designed to help support urinary tract health by combining five strains of Lactobacillus shown effective in the prevention and treatment of UTIs—L. plantarum, L. gasseri, L. fermentum, L. reuteri, L. brevis—with added Cran-Gyn and D-mannose.
Expert Review of Anti-infective Therapy
The role of the host-microbe ecosystem (microbiome) in health and disease is of growing scientific interest as evidenced by the National Institutes of Health (NIH) Human Microbiome Project , , , ], the Metagenomics of the Human Intestinal Tract (MetaHIT) consortium , , , ] and the United States’ National Microbiome Initiative , , , ]. These initiatives recognize the complexity of the human microbiome in terms of composition, functions, dynamics, and interrelationships and its potential link to, and for treating/preventing, a range of diseases. Notably, microorganisms in the human gastrointestinal tract have been shown to influence physiological processes including immune function , , , ]. This has increased research aimed at developing novel microbiome-based treatment and prevention approaches. One intriguing possibility is the use of probiotics to improve the composition of the microbiota in favor of beneficial microorganisms. This approach has been tried in a number of infectious diseases, with the goal of limiting the activity of pathogenic bacteria , , ].
Urinary tract infections (UTIs), the focus of our study, have been estimated to affect >50% of women at some stage in their lives , , , ], and between 25 and 30% of these individuals have at least one recurrence after the first infection , , , ]. As such, they represent a major clinical challenge in community practice, and they place a significant financial burden on healthcare systems , , , ]. The most common pathogens associated with UTIs belong to the Enterobacteriaceae family (Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Citrobacter spp. and Enterobacter spp.) , , , ]. Uropathogenic E. coli (UPEC) are a heterogeneous group of extra-intestinal E. coli that originate in the rectal microbiota and they account for approximately 80% of uncomplicated UTIs, and 95% of community-acquired UTIs , , , –10 Nosseir SB, Lind LR, Winkler HA. Recurrent uncomplicated urinary tract infections in women: a review. J Womens Health (Larchmt). 2012;21:347–354., , , ]. The current strategy for managing UTIs is based on a combination of lifestyle measures and antibacterial therapy , , , ,8 Asadi Karam MR, Habibi M, Bouzari S. Urinary tract infection: pathogenicity, antibiotic resistance and development of effective vaccines against uropathogenic Escherichia coli. Mol Immunol. 2019;108:56–67., , , ,11 Flores-Mireles AL, Walker JN, Caparon M, et al. Urinary tract infections: epidemiology, mechanisms of infection and treatment options. Nat Rev Microbiol. 2015;13:269–284., , , ]. In women with recurrent UTIs, continuous prophylaxis with low-dose antibacterial regimens has been recommended , , ]. However, the routine use of low-dose, daily antibiotics is now being questioned because of the widespread emergence of antibiotic-resistant strains , , , ,8 Asadi Karam MR, Habibi M, Bouzari S. Urinary tract infection: pathogenicity, antibiotic resistance and development of effective vaccines against uropathogenic Escherichia coli. Mol Immunol. 2019;108:56–67., , , ,11 Flores-Mireles AL, Walker JN, Caparon M, et al. Urinary tract infections: epidemiology, mechanisms of infection and treatment options. Nat Rev Microbiol. 2015;13:269–284., , , ]. In particular, antimicrobial resistance in uropathogenic E. coli is a concern , , , ,14 Howard AJ, Magee JT, Fitzgerald KA, et al. Factors associated with antibiotic resistance in coliform organisms from community urinary tract infection in Wales. J Antimicrob Chemother. 2001;47:305–313., , , ] and the availability of alternative treatments is important. Furthermore, antibacterial drugs have been linked to gut and vaginal dysbiosis which is also a potential cause of recurrent infections , , , ].
A recent novel approach is the use of natural products, such as probiotics and cranberry supplements, that act on the microbiome to reduce colonization by uropathogens. The basis for this strategy is the strong link between vaginal health and UTIs, and the finding that pathogenic bacteria colonizing the female urinary tract are associated with ascending colonization from the fecal flora , , , ]. Indeed, the link between the microbiome and urological health and disease is of increasing clinical interest and has given rise to the concept of the female urinary microbiota , , , ,17 Whiteside SA, Razvi H, Dave S, et al. The microbiome of the urinary tract–a role beyond infection. Nat Rev Urol. 2015;12:81–90., , , ]. This mode of therapy also avoids the complication of dysbiosis frequently seen with broad-spectrum antibacterial treatment , , , ].
Studies have shown that women with no history of UTIs had a Lactobacilli-dominant vaginal microbiota with the most common strains being Lactobacillus crispatus, Lactobacillus jensenii, and Lactobacillus iners, whilst patients suffering from recurrent UTIs were comparatively depleted of Lactobacilli , , ,18 Reid G, Bruce AW. Probiotics to prevent urinary tract infections: the rationale and evidence. World J Urol. 2006;24:28–32., , , ]. Based on these findings it has been suggested that commensal Lactobacillus spp. may help protect the vagina from invading uropathogens , , , ,9 Butler DSC, Silvestroni A, Stapleton AE. Cytoprotective effect of Lactobacillus crispatus CTV-05 against uropathogenic E. coli. Pathogens. 2016;5:27., , ]. This is the theory behind the administration of Lactobacilli-based probiotics to help maintain and restore a healthy microbiota effective in inhibiting colonization by uropathogens , , , ,9 Butler DSC, Silvestroni A, Stapleton AE. Cytoprotective effect of Lactobacillus crispatus CTV-05 against uropathogenic E. coli. Pathogens. 2016;5:27., , ,19 Reid G, Bruce AW, Fraser N, et al. Oral probiotics can resolve urogenital infections. FEMS Immunol Med Microbiol. 2001;30:49–52., , , –21 Reid G, Charbonneau D, Erb J, et al. Oral use of Lactobacillus rhamnosus GR-1 and L. fermentum RC-14 significantly alters vaginal flora: randomized, placebo-controlled trial in 64 healthy women. FEMS Immunol Med Microbiol. 2003;35:131–134., , , ]. However, despite the promising potential of probiotics to prevent UTIs in the community, most randomized controlled trials up to 2015, as reviewed by the Cochrane group, failed to identify any significant clinical benefit , , , ].
Likewise, in a Cochrane review in 2012 involving 24 trials and >4000 patients, cranberry supplementation did not have a statistically significant benefit in preventing symptomatic UTIs , , , ]. Products such as tablets or capsules were also ineffective, although they had the same effect as taking antibiotics , , , ]. In two meta-analyses, both published in 2017, cranberry products were shown to reduce the risk of UTI recurrence by 26% , , , ] and 33% , , , ]. A drawback of the studies involving tablets and capsules was that few reported how much active ingredient was administered. This is important since it has been shown that at least 36 mg of cranberry proanthocyanidin (PAC) equivalents/d, divided into two doses (morning and evening), is needed to impart the anti-adhesion bioactivity thought to be necessary to prevent bacterial adhesion to uroepithelial cells lining the bladder wall , , , ,26 Howell AB, Botto H, Combescure C, et al. Dosage effect on uropathogenic Escherichia coli anti-adhesion activity in urine following consumption of cranberry powder standardized for proanthocyanidin content: a multicentric randomized double blind study. BMC Infect Dis. 2010;10:94. ., , , ]. The authors noted that more studies of tablets and capsules may be justified, but only if the recommended amount of PAC (at least 36 mg/d) is administered , , , ].
Based on these findings we investigated the efficacy and safety of Bio-Kult Pro-Cyan (BKPro-Cyan), a commercially available product containing probiotic strains (Lactobacillus acidophilus PXN 35, Lactobacillus plantarum PXN 47) and cranberry extract (36 mg/d PACs), for preventing recurrent uncomplicated UTIs in premenopausal adult women.