Recurrent UTIs: Facts vs Fiction

Educational Objectives

The goal of this program is to improve management of recurrent urinary tract infections (UTI). After hearing and assimilating this program, the clinician will be better able to:

1. Differentiate between recurrent and relapsed UTI.
2. Use imaging to diagnose anatomic malformations in recurrent UTI.

Summary

Definitions: recurrent urinary tract infection (UTI) is defined as the occurrence of ≥3 culture-proven infections within a 12-mo period or ≥2 episodes in 6 mo; reinfection is defined as another separate chronologic infection with the same organism; relapsed infection is defined as infection with the same organism, usually 2 to 4 wk after completing treatment; a persistent infection involves a shorter duration of recurrence, usually occurring within days, which suggests that the infection may not have been fully eradicated

Asymptomatic bacteriuria: a true infection typically presents with symptoms; asymptomatic bacteriuria is defined as a positive urine culture without any symptoms; this condition may indicate colonization; treatment is not necessary or recommended, as it can lead to an overgrowth of Enterococcus faecalis and other organisms that are challenging to manage

Risk factors for recurrent infections in women: premenopausal — recurrent infections are often linked to sexual intercourse; more frequent intercourse or having a new partner can increase the risk by ≤9 times; the use of oral contraceptives and spermicides (specifically foam or gel) can lead to periurethral colonization by Escherichia coli, resulting in imbalances and infections; a history of urinary infections in childhood, recurrent UTIs in the patient’s mother, previous unnecessary treatments with antibiotics for asymptomatic bacteriuria, and dysfunctional voiding patterns (eg, contraction of the urinary sphincter while voiding) can also predispose to UTIs; postmenopausal — atrophic vaginitis refers to postmenopausal changes caused by lower estrogen, leading to decreased population of lactobacilli and other “good” bacteria that help prevent colonization by uropathogens; urinary incontinence is more common in postmenopausal women, leading to increased colonization of the perineum and higher infection rates; risk factors include a history of infections prior to menopause, being a nonsecretor of blood group antigens, childhood UTIs, anatomic issues (eg, bladder prolapse or cystocele with an inability to empty the bladder), and high postvoid residual; other more debated risk factors (weak evidence) include low fluid intake, delaying or avoiding urination after urination, direction of wiping after bowel movements, types of underwear material, use of hot tubs, and body mass index

Diagnostic workup: includes a history, physical examination, possible pelvic examination in women, and urinalysis with microscopic examination instead of a urine dip test; culture and sensitivity testing is warranted before each treatment, and the test should be repeated if the culture is contaminated; if the patient cannot obtain a good specimen, a catheterized specimen using sterile technique may be needed to avoid contamination; a urologic workup involves assessing the entire urinary tract; upper tract sources may include kidney stones colonized by bacteria; anatomic malformations can be detected with computed tomography urography or renal ultrasonography; sometimes, a urologist may obtain lateralizing cultures, ie, specific cultures from the left and right kidneys, for repeated UTI; this is a surgical procedure, and antibiotics are not initiated prior to the induction of anesthesia (only after both samples are obtained); the lower tract is assessed with cystoscopy; check the postvoid residual; a significant amount of retention is >100 mL

Treatment strategies: antibiotics are recommended for ≤1 wk in most patients, including complex cases; treatment should ideally be based on culture and sensitivity; for classic recurrent UTIs or “honeymoon cystitis,” it is advisable to provide refills of nitrofurantoin (Macrobid) so patients can initiate therapy themselves after submitting their urine sample; antibiotic prophylaxis is less favored because of the risk of causing antibiotic resistance; the preferred method, especially for postcoital recurrent infections, is to give one single dose after intercourse (although this can introduce resistance); educate the patient about the risk factors of frequent intercourse, multiple partners, and spermicide; provide education about asymptomatic bacteriuria; after menopause, offer topical estrogens for atrophic vaginitis; hydration and voiding after intercourse may help

Alternative treatments: for recurrent infections due to chronic debilitation, catheters, or an occult source that cannot be eradicated, methenamine hippurate (eg, Hiprex, UREX) is preventative; it converts into formaldehyde in the urine preventing most of infections; vaginal or oral probiotics do not prevent UTIs; D-mannose (in cranberry) blocks the adhesion of bacteria, specifically E coli, that have type-1 fimbriae that adhere to the host cells; D-mannose blocks this process and makes it harder for the bacteria to colonize; the dose is 2 g per day and is usually well-tolerated (it may cause some gastrointestinal disturbance); however, it does not protect against other uropathogens; proanthocyanidin (PAC) A from cranberry extract works in similar way (it is thought to prevent E coli adhesion to the host cells by blocking the fimbriae); the dose is ≈300 mL of juice per day or 72 mg of the PAC powder daily

Future directions: vaccines are being investigated that either work on antibody-mediated immunity against infection or T cell activation to tackle the cellular immunity pathway to prevent UTI; investigators are looking into raising natural host defenses by intravesical glycosaminoglycans (eg, hyaluronic acid) or by competitive inoculation with good bacteria (ie, less pathogenic strains of E coli or other pathogens)

Readings

Ala-Jaakkola R, Laitila A, Ouwehand AC, et al. Role of D-mannose in urinary tract infections - a narrative review. Nutr J. 2022;21(1):18. doi:10.1186/s12937-022-00769-x; Aydin A, Ahmed K, Zaman I, et al. Recurrent urinary tract infections in women. Int Urogynecol J. 2015;26(6):795-804. doi:10.1007/s00192-014-2569-5; Gupta K, Grigoryan L, Trautner B. Urinary Tract Infection. Ann Intern Med. 2017;167(7):ITC49-ITC64. doi:10.7326/AITC201710030; Heltveit-Olsen SR, Sundvall PD, Gunnarsson R, et al. Methenamine hippurate to prevent recurrent urinary tract infections in older women: protocol for a randomised, placebo-controlled trial (ImpresU). BMJ Open. 2022;12(11):e065217. doi:10.1136/bmjopen-2022-065217; Juma S. Urinary retention in women. Curr Opin Urol. 2014;24(4):375-79. doi:10.1097/MOU.0000000000000071; Kim JM, Park YJ. Probiotics in the prevention and treatment of postmenopausal vaginal infections: review article. J Menopausal Med. 2017;23(3):139-45. doi:10.6118/jmm.2017.23.3.139.

Disclosures

For this program, members of the faculty and planning committee reported nothing relevant to disclose.

Acknowledgements

Dr. Akhavein was recorded at the 2023 What’s New in Urology: A Primer for the Primary Care Provider CME Activity, held on April 22, 2023, in Los Angeles, CA, and presented by the Cedars-Sinai Medical Center. For more information on upcoming CME activities from this presenter, please visit https://cedars.cloud-cme.com. Audio Digest thanks the speakers and the presenters for their cooperation in the production of this program.

CME/CE INFO

Accreditation:

The Audio- Digest Foundation is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians.

The Audio- Digest Foundation designates this enduring material for a maximum of 0.50 AMA PRA Category 1 Credits™. Physicians should claim only the credit commensurate with the extent of their participation in the activity.

Audio Digest Foundation is accredited as a provider of continuing nursing education by the American Nurses Credentialing Center's (ANCC's) Commission on Accreditation. Audio Digest Foundation designates this activity for 0.50 CE contact hours.

Lecture ID:

IM721502

Expiration:

This CME course qualifies for AMA PRA Category 1 Credits™ for 3 years from the date of publication.

Instructions:

To earn CME/CE credit for this course, you must complete all the following components in the order recommended: (1) Review introductory course content, including Educational Objectives and Faculty/Planner Disclosures; (2) Listen to the audio program and review accompanying learning materials; (3) Complete posttest (only after completing Step 2) and earn a passing score of at least 80%. Taking the course Pretest and completing the Evaluation Survey are strongly recommended (but not mandatory) components of completing this CME/CE course.

Estimated time to complete this CME/CE course:

Approximately 2x the length of the recorded lecture to account for time spent studying accompanying learning materials and completing tests.