II. Definitions

  1. Recurrent Urinary Tract Infection in young women
    1. One year with 3 or more symptomatic, culture positive Urinary Tract Infections
  2. Recurrent Urinary Tract Infection in postmenopausal women
    1. One year with 3 or more symptomatic, culture positive Urinary Tract Infections OR
    2. Six months with 2 or more Urinary Tract Infections
  3. UTI Relapse
    1. UTI with same organism and serotype presents within 2 weeks of last UTI treatment

III. Epidemiology

  1. Incidence of bacteriuria
    1. School age child: 1.2%
    2. Late Teenage years: 2-5%
    3. Additional 1% per decade of life
  2. Incidence of UTIs for those prone: 2-3 per year
    1. Reduced to <1 per year on prophylaxis

IV. Pathophysiology

  1. Causative organisms
    1. Escherichia coli (75% of Recurrent UTI)
    2. Enterococcus faecalis
    3. Proteus mirabilis
    4. Klebsiella
    5. Staphylococcus saprophyticus
  2. Inherited factors (esp. in first degree relative with >5 UTIs)
    1. Immune susceptibility (e.g. variation in Neutrophil receptors)
      1. May reduce Bacterial clearance or not preventing uroepithelial adherence
    2. Urogenital anatomy variation
      1. Shorter anal-Urethral distance

V. Types: Infection Classification

  1. General
    1. Reinfection represents 99% of Recurrent UTI in women
    2. Vaginal colonization is the most common cause
  2. First Infection
  3. Unresolved Bacteriuria (Refractory Infection)
    1. Bacterial resistance to drug selected for treatment
      1. Resistance developed by sensitive Bacteria
      2. Bacteriuria with 2 different species
      3. Rapid reinfection with a second resistant organism
    2. Azotemia
    3. Analgesic abuse causing papillary necrosis
    4. Giant staghorn calculi
    5. Noncompliance
  4. Bacterial persistance (Same organism recurs)
    1. Infected Renal Calculi
    2. Chronic Bacterial Prostatitis
    3. Unilateral infected atrophic Pyelonephritis
    4. Infected pericalyceal Diverticulae
    5. Infected nonrefluxing ureteral stumps
      1. Follows Nephrectomy
    6. Medullary sponge Kidneys
    7. Polycystic Kidney Disease
    8. Infected Urachal Cysts
    9. Analgesic abuse causing infected papillary necrosis
  5. Reinfection (Urine cleared, but new infection occurs)
    1. Colonization of vaginal introitus
    2. Vesicoenteric fistulae
    3. Vesicovaginal fistulae
    4. Vesicoureteral Reflux
    5. Voiding dysfunction
      1. Cystocele
      2. Multiple Sclerosis
      3. Neurogenic Bladder
    6. Immunosuppression
      1. Chronic Renal Insufficiency
      2. Diabetes Mellitus
      3. Immunosuppressant medications
    7. Instrumentation
      1. Ureteral Stent
      2. Nephrostomy Tube
      3. Intermittent catheterization or indwelling Urinary Catheter

VI. Risk Factors

  1. Young women with Recurrent UTI (prior to Menopause)
    1. Intercourse in the past month >9 times: Odds Ratio 10.3
    2. Intercourse in the past month 4-8 times: Odds Ratio 5.8
    3. Age at first UTI >15 years: Odds Ratio 3.9
    4. Mother with Recurrent UTI: Odds Ratio 2.3
    5. New sex partner in the last year: Odds Ratio 1.9
    6. Spermicide use in the last year: Odds Ratio 1.8
    7. Scholes (2000) J Infect Dis 182(4): 1177-82 [PubMed]
  2. Postmenopausal women
    1. Estrogen deficiency alters Vaginal pH and decreases Lactobacillus colonization
    2. Incontinence
    3. Urinary Retention (residual Urine Volume >150 ml)
    4. Structural abnormalities (e.g. Cystocele)
    5. Type II Diabetes Mellitus
    6. History of Urinary Tract Infection (>5)
    7. Activities that increase intraabdominal pressure (e.g. long distance travel or walking)

VII. Differential Diagnosis

  1. See Dysuria
  2. Consider Vaginitis or Sexually Transmitted Infection
  3. Consider other noninfectious causes (e.g. Interstitial Cystitis, Bladder Cancer)

VIII. Labs

  1. Urinalysis
  2. Consider Urine Pregnancy Test
  3. Urine Culture indications
    1. Obtain in at least one of Recurrent Urinary Tract Infections
    2. Breakthrough Urinary Tract Infection while on UTI prophylaxis
    3. UTI symptoms >48 hours despite antibiotic treatment
    4. Symptomatic bacteriuria at 2 weeks after 2 weeks of culture-directed antibiotics
      1. Evaluate for Antibiotic Resistance or persistent infection nidus

IX. Diagnostics

  1. Post-void Residual Volume and urodynamic testing indications
    1. Urinary Incontinence or Overactive Bladder
    2. Incomplete Bladder emptying
  2. Structural evaluation (pelvic exam, Ultrasound, CT, cystoscopy) indications
    1. Hematuria persists after infection clearance
    2. Urinary tract malignancy history
    3. Urogenital surgery or Trauma History
    4. Diverticulitis history
    5. Nephrolithiasis or Urolithiasis
      1. Especially if Urine Culture with Proteus, Klebsiella, Pseudomonas (associated with Struvite Stones)
    6. Multi-drug resistant organisms
    7. Persistent symptoms and bacteriuria despite 2 weeks of culture directed antibiotics
    8. Pneumaturia or fecaluria
    9. Urine Culture with anaerobic organisms (except E. coli, Staphylococcus)
    10. Recurrent or treatment-resistant Pyelonephritis
    11. Voiding dysfunction
      1. Urinary obstructive symptoms
      2. Increased post-void Residual Volume
      3. Urinary Incontinence

X. Management: Urinary Tract Infection Treatment

  1. See Urinary Tract Infection for acute management
  2. First-line agents (less likely to induce Antibiotic Resistance)
    1. Trimethoprim-sulfamethoxazole or Septra, Bactrim (3 days)
    2. Nitrofurantoin or Macrobid (5 days)
    3. Fosfomycin or monurol (1 day)
  3. Other agents
    1. Reserve Fluoroquinolones (e.g. Ciprofloxacin, Levofloxacin) for more complicated infections
    2. Beta lactam agents (Penicillins, Cephalosporins) are less effective in Recurrent UTI
  4. Precautions
    1. Treat uncomplicated cystitis with three day course
    2. Outside pregnancy, avoid treating asymptomatic residual bacteriuria after treatment
    3. Treat uncomplicated cystitis in Diabetes Mellitus with same agents as those without diabetes
  5. Urology Consultation indications
    1. Hematuria without Dysuria
    2. Serum Creatinine increased
    3. Recurrent Proteus infections
    4. Urinary Retention and Incontinence

XI. Management: Antibiotic self-starting regimen for symptomatic UTI

  1. Emergency prescription available to start after onset of classic Urinary Tract Infection symptoms
    1. Self diagnosis based on Dysuria, Urinary Frequency, urinary hesitancy is 85% accurate
  2. Choose a 3 day antibiotic course
    1. See Urinary Tract Infection for antibiotic options and dosing
  3. Indications for medical evaluation
    1. Symptoms last more than 48 hours despite antibiotics
    2. Fever
    3. Nausea or Vomiting
    4. Acute back pain
    5. Vaginal Discharge
    6. Pelvic Pain
    7. STD Exposure
  4. Contraindications
    1. Prior urogenital surgery
    2. Bladder Catheterization
  5. References
    1. Schaeffer (1999) J Urol 161(1):207-11 +PMID:10037399 [PubMed]

XII. Management: UTI Prophylaxis in women

  1. Indications
    1. Recurrent Urinary Tract Infections occurring 3 or more times annually
  2. Continuous UTI Prophylaxis (Average Course: Taken daily for 6 months, up to 12 months)
    1. Preferred first-line continuous prophylaxis (choose one)
      1. Nitrofurantoin 50-100 mg once daily
      2. Trimethoprim Sulfamethoxazole 40/200 daily or three times per week
    2. Other agents used for continuous prophylaxis (choose one)
      1. Trimethoprim 100 mg daily
      2. Cephalexin 125-250 mg daily
    3. Generally avoid for continuous prophylaxis (risk of increasing resistance)
      1. Ciprofloxacin 125 mg daily
      2. Norfloxacin 200 mg daily
  3. Postcoital Prophylaxis
    1. Precaution: Recurrence is common after stopping prophylaxis
    2. One dose taken within 2 hours of intercourse
    3. Preferred first-line post-coital prophylaxis (choose one)
      1. Nitrofurantoin 100 mg once
      2. Trimethoprim Sulfamethoxazole 40/200 to 80/400 once
    4. Other agents used for post-coital prophylaxis (choose one)
      1. Trimethoprim 100 mg once
      2. Cephalexin 250 mg once
    5. Generally avoid for post-coital prophylaxis (risk of increasing resistance)
      1. Ciprofloxacin 125 mg once
      2. Norfloxacin 200 mg once
  4. Post-menopausal women
    1. Topical Estrogen for Atrophic Vaginitis
      1. Estriol Cream 0.5 mg intravaginal daily for 2 weeks initially, then twice weekly
      2. Perotta (2008) Cochrane Database Syst Rev (2):CD005131 +PMID:18425910 [PubMed]

XIII. Management: Other prophylactic agents

  1. Methenamine
    1. Dose: 1 g orally twice daily
    2. Preparations
      1. Methenamine Hippurate
      2. Methenamine Mandelate
    3. Indications
      1. Short term prophylaxis in patients without renal tract abnormalities
    4. References
      1. Weidner (2018) Email communication, received 9/1/2018
      2. Lee (2012) Cochrane Database Syst Rev (10): CD003265 +PMID: 23076896 [PubMed]
  2. Cranberry Juice (variable evidence)
    1. Mechanism
      1. Contains proanthocyanidin compounds
      2. Inhibits E. coli from adhering to urinary tract
    2. Recommended daily dosing of cranberry juice
      1. Cranberry extract 300-400 mg tablet bid or
      2. Pure cranberry unsweetened juice 8 ounces tid
    3. Efficacy
      1. No high quality evidence for significant benefit
        1. Guay Drugs (2009) 69(7):775-807 [PubMed]
      2. Not effective in older women living in Nursing Homes
        1. Juthani-Mehta (2016) JAMA 316(18):1879-87 +PMID: 27787564 [PubMed]
      3. Daily cranberry juice may decrease recurrent symptomatic UTIs in women over 1 year
        1. Jepson (2008) Cochrane Database Syst Rev (1):CD001321 +PMID:18253990 [PubMed]
      4. Older, original studies suggesting more broad efficacy in UTI prevention
        1. Kontiokari (2001) BMJ 322:1571-3 [PubMed]
        2. Howell (1998) N Engl J Med 339(15): 1085-86 [PubMed]
        3. Lynch (2004) Am Fam Physician 70(11): 2175-77 [PubMed]

XIV. Prevention: Behavior Modification

  1. Measures that may offer benefit
    1. Women should empty Bladder before and after intercourse
    2. Avoid Contraceptive Diaphragm
    3. Avoid spermacide
    4. Increased hydration (1.5 extra Liters/day)
      1. Hooton (2018) JAMA Intern Med 178(11):1509-15 [PubMed]
  2. Measures NOT found to reduce UTI risk
    1. Women wiping perineum front to back after stooling
    2. Cotton underwear
    3. Reduced exposure to hot tubs
    4. Reduced use of tampons
    5. Avoid douching (did not decrease UTI risk, but should be avoided due to other risks)
    6. Glover (2014) Urol Sci 25(1): 1-8 [PubMed]

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