According to the Centers for Disease Control (CDC), urinary tract infections account for more than 30% of infections reported by acute care hospitals. With the increasing bacterial resistance against antibiotics and drug adverse effects, probiotics, such as lactobacilli, have become a special interest to healthcare professionals and sufferers.
Types of UTI
Urinary tract infections (UTIs) are generally considered "lower" or "upper," according to where they occur along the tract. Upper UTIs include infections of the bladder (cystitis), prostate (prostatitis), epididyimis (epididymitis), and of the urethra (urethritis). Upper-tract disease is called pyelonephritis, or infection of the kidney.
Causes of UTI
More than 85% of urinary tract infections are the result of a bacterial infection, mostly E. coli. Other possible causes are: viruses, fungi, and parasitic worms. Lactobacilli do not normally cause disease. When they are involved in UTI development, it is usually because the patient has an underlying disease, a weakened immune system, or an abnormal urinary tract.
Types of Lactobacilli
In the genito-urinary tract, some of the most common members of the lactobacilli species are: L. crispatus, L. jensenii, and L. iners. Though rare, some lactobacilli that have been involved in UTI development are L. gasseri and L. delbrueckii.
Lactobacilli produce lactic acid, and are the dominant bacteria of the vaginal flora of healthy women. They are generally considered "good" bacteria because they have antimicrobial properties that control the growth of disease-causing micro-organisms. When urinary tract infections are not properly treated or recur, the normal balance between organisms in the vagina changes, decreasing the number of protective lactobacilli. As a result, the affected person becomes even more vulnerable to infection.
Factors that negatively affect the growth of lactobacilli include: antibiotic therapy, oral contraceptives, a previous history of UTI, and menstrual cycle. During a period, the number of lactobacilli is reduced because the blood flow increases the pH of the vagina (i.e., it makes it less acidic).
The detection of lactobacilli in the urine is often the result of contamination during the diagnosis process. Therefore, true urinary infection from a lactobacillus usually needs to be confirmed by obtaining and analyzing urine samples through a different method. Two specific procedures for the collection of uncontaminated bladder urine are: urethral catheterization and supra-pubic aspiration.