Urinary Tract Infections Are Among the Most Common Bacterial Infections Reported in the US

By the age of 32, more than 50 out of every 100 woman report having had at least one urinary tract infection (UTI), with a lifetime occurrence of up to 70 out of every 100 woman; up to 25 out of every 100 of these woman will experience a recurrence. This condition results in tremendous cost to the healthcare system in the diagnosis and management of UTIs with an estimated $3.5 billion spent in 2000.

 Most UTIs are caused by an ascending infection in which bacteria enters the urinary tract through the opening of the bladder, the urethra. Women have specific risk factors including a short urethra that is in close proximity to the vagina and anus, as well as colonization of the lower 1/3 of the urethra with vaginal or gut bacteria, which may be introduced into to the bladder during vaginal intercourse. Other risk factors include diabetes, old age with ” dry vagina”-atrophic  vaginitis, frequent and recent sexual activity, poor perineal hygiene, and pelvic organs falling out -advanced pelvic organ prolapse. The most common bacteria causing UTI is  E. Coli.

When the infection is in the bladder it is called acute cystitis. Patients will  typically have painful urination in conjunction with urgency ( have to go now), frequency ( have to go frequently ), and suprapubic pain (pain above the pubic bone). Blood in the urine (hematuria) is less common. A urine culture is performed to confirm the correct bacteria  and the appropriate antibiotic therapy. Ultrasound of the kidneys is only recommended  in patients with poor response to antibiotic therapy, suspected unusual organisms or recurrent infections.

First-line therapy includes Nitrofurantoin, Trimethoprim-sulfamethoxazole and Fosfomycin with efficacy rates ranging from 84-100%. Cipro should be reserved for resistant organisms and avoided as first-line therapy secondary to potential collateral damage. Amoxicillin and Ampicillin should be avoided as  treatment due to the high resistance rates worldwide.

Questions

Can I self-diagnose?

A study to determine the safety and feasibility of patient-initiated treatment of recurrent UTI’s demonstrated that self-diagnosis and treatment of UTIs based on symptoms was 85-95% effective, and thus may potentially eliminate the need for office evaluation in uncomplicated cases.

How about after intercourse? 

Use of antibiotics after sexual intercourse – post-coital antibiotics are very ( 92%) effective and are another strategy for preventing UTI’s in women at risk for frequent infections.

How do I know I have a recurrent infection?

You have a recurrent infection if you have more than  2 UTIs in 6 months or more than 3 in one year. You may be given continuous antibiotics for  suppression for 6 months to prevent recurrences, however up to 50 out of every 100 such women will experience recurrent UTI’s after discontinuation of the suppression medications.

Do hormones help?

The use of vaginal, but not oral, estrogen in postmenopausal women is effective in reducing recurrent cystitis.

Can I just drink a lot of cranberry juice?

Other strategies for the prevention of recurrent uncomplicated cystitis which have theoretical plausibility include pee after intercourse -postcoital voiding, adhesion blockers (D-Mannose), cranberry juice or supplements, agents that acidify urine, and probiotics. Although the data is insufficient to recommend their routine use, there is little risk of adverse events while providing possible benefit.

Key Points

1. Women have specific risk factors that make them more susceptible to developing cystitis.

2. Self-diagnosis and treatment based on symptoms, is an effective strategy in uncomplicated cases.

3. First-line antimicrobial treatment should avoid fluoroquinolones due to the potential for collateral damage.

4. Post-coital antibiotics is 92% effective in preventing acute cystitis.

5. Radiological studies and cystoscopy should be reserved for recurrent, complicated cases.

6. Vaginal estrogen therapy is an effective strategy in preventing recurrent cystitis in postmenopausal women.

7. Other preventative strategies such as post-coital voiding, cranberry products, adhesion blockers and probiotics may be useful, and carry little risk.

References 

1. American College of Obstetricians and Gynecologists. Treatment of urinary tract infections in nonpregnant women. Practice Bulletin 91, 2008, Obstet Gynecol 2008;111:785–94

2. Hooten TM. Uncomplicated urinary tract infection. N Engl J Med 2012;366:1028-37

3. Gupta K, Hooton TM, Naber K, Wullt B, Colgan R, Miller LG, et al. International clinical practice guidelines for the treatment of acute uncomplicated cystitis and pyelonephritis in women: A 2010 Update by the Infectious Diseases Society of America and the European Society for Microbiology and Infectious Diseases. Clin Infect Dis 2011;52(5):e103–e120

4. Gupta K, Hooton TM, Roberts PL, Stamm WE. Patient initiated treatment of uncomplicated recurrent urinary tract infections in young women. Ann Intern Med 2001;135:9-1

Leave a Reply