Genitourinary infection: Difference between revisions

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#Known or suspected abx resistance (resistance to Cipro predicts multidrug resistance)
#Known or suspected abx resistance (resistance to Cipro predicts multidrug resistance)


===Bacteriology===
===[[Microbiology]]===
*Most common pathogen is [[E. coli]]
*Most common pathogen is [[E. coli]]
*[[Anaerobic]] organisms are rarely pathogenic (do not grow well in urine)
*[[Anaerobic]] organisms are rarely pathogenic (do not grow well in urine)

Revision as of 12:05, 23 December 2014

Background

Definitions

  • UTI = significant bacteriuria in presence of symptoms
    • Described by location: urethritis, cystitis, or pyelonephritis
  • Relapse
    • Recurrence of symptoms w/in month despite tx
      • Caused by same organism and represents treatment failure
  • Reinfection
    • Development of symptoms 1-6mo after tx
    • Usually due to a different organism
    • If pt has >3 recurrences in 1 yr consider tumor, calculi, diabetes
  • Men <50 yr: symptoms of dysuria or urinary frequency usually due to STI
  • Men >50 yr: incidence of UTI rises dramatically d/t prostatic obstruction
  • Uncomplicated UTI:
    • No structural or functional abnormalities w/in urinary tract or kidney
    • No relevant comorbidities that place pt at risk for more serious adverse outcome
    • Not associated with GU tract instrumentation

Risk factors for complicated UTI

  1. Male sex
    1. In young males dysuria is more commonly d/t STI
    2. Suspect underlying anatomic abnormality in men with culture-proven UTI
  2. Anatomic abnormality of urinary tract or external drainage system
    1. Indwelling urinary catheter, stent
    2. Nephrolithiasis, neurogenic bladder, polycystic renal disease, recent instrumentation
  3. Recurrent UTI (three or more per year)
  4. Advanced age in men (BPH, recent instrumentation, recent prostatic biopsy)
  5. Nursing home residency (w/ or w/o indwelling bladder catheter)
  6. Neonatal state
  7. Comorbidities (DM, sickle cell disease)
  8. Pregnancy
  9. Immunosuppression (AIDS, immunosuppressive drugs)
  10. Advanced neurologic disease (CVA w/ disability, Spinal Cord Injuries)
  11. Known or suspected atypical pathogens (Non–E. coli infection)
  12. Known or suspected abx resistance (resistance to Cipro predicts multidrug resistance)

Microbiology

Diagnosis

Clinical Features

  • UTI dx requires both bacteriuria and clinical symptoms
    • Cystitis = Dysuria, hematuria, frequency, urgency, suprapubic pain, CVAT
    • Pyelo = Cystitis sx AND fever/chills/nausea/vomiting
      • CVAT alone may be referred pain from cystitis
      • CVAT is only physical examination finding that increases likelihood of a UTI
  • Urethritis
    • In males more likely due to chlamydia/GC
    • In females more likely due to chlam/GC if:
      • Stuttering urination symptoms
      • New sex partner or partner w/ urethritis
      • Signs/symptoms cervicitis
      • Sterile pyuria
  • Complicated UTI

Labs

UA

WBC count
  • WBC >5 in pt w/ appropriate symptoms is diagnostic
    • Lower degrees of pyuria may still be clinically significant in presence of UTI sx
      • False negative may be due to: dilute urine, systemic leukopenia, obstruction
    • WBC 1-2 w/ bacteriuria can be significant in men
Nitrite
  • Very high specificity (>90%) in confirming diagnosis of UTI
  • Low sensitivity (enterococcus, pseudomonas, acinetobacter are not detected)

Urine Culture

  • Indicated for:
    • Complicated UTI
    • Pyelonephritis
    • Pregnant women
    • Children
    • Adult males
    • Relapse/reinfection

Blood Culture

  • Not indicated
    • Organisms in blood cx matched those in urine cx 97% of time

Imaging

  1. History of Renal Stone
  2. Poor response to antibiotics
  3. Male
  4. Elderly
  5. Diabetic
  6. Severely ill

Differential Diagnosis

Major

  • Pyelonephritis
  • Infected kidney stone

Pelvic Pain

Acute Pelvic Pain

Differential diagnosis of acute pelvic pain

Gynecologic/Obstetric

Genitourinary

Gastrointestinal

Musculoskeletal

Vascular

Dysuria

Dysuria

Management

  • Consider local resistance patterns (if >10-20% use a different agent)
  • Avoid use of fluoroquinolones for uncomplicated cystitis if possible
Consider longer course of complicated cystitis if
  • Symptoms >7d
  • DM
  • UTI in previous 4wk
  • Men
  • Age 65 yr
  • Women who use spermicides or diaphragm
  • Relapse
  • Pregnancy

Outpatient

Women, Uncomplicated

  • Nitrofurantoin ER 100mg BID x 5d, OR
  • TMP/SMX DS (160/800mg) 1 tab BID x 3d, OR
  • Cephalexin 250mg QID x 5d, OR
  • Ciprofloxacin 250mg BID x3d
    • Avoid using fluoroquinolone for the first-line treatment of uncomplicated urinary tract infections (UTIs) in women.[2]
  • Fosfomycin 3 g PO once
    • Lower clinical and microbiologic success compared to nitrofurantoin TID for 5 days [3]

Women, Complicated

Women, Concern for Urethritis

Men

Inpatient Options

Disposition

Uncomplicated UTI

  • Admit
    • Unable to tolerate PO
  • Discharge
    • Consider phenazopyridine 100-200mg TID after meals x2d only (bladder analgesic)

Pyelonephritis

  • Discharge
    • Consider if young, otherwise healthy, tolerating PO
  • Admission
    • Consider if elderly, Renal Calculi, obstruction, recent hospitalization/instrumentation, DM

Complications

  • Suspect in pts who have inadequate or atypical response to tx for presumed pyelonephritis
  1. Acute bacterial nephritis
    1. CT shows ill-defined focal areas of decreased density
  2. Renal/Perinephric Abscesses
    1. Sign/symptoms similar to pyelo (fever, CVAT, dysuria)
    2. Occurs in setting of ascending infection w/ obstructed pyelo
    3. Associated w/ DM and Renal Stones
    4. Also occurs due to bacteremia w/ hematogenous seeding (Staph)
  3. Emphysematous pyelonephritis
    1. Rare gas-forming infection nearly always occurring in pts w/ DM and obstruction
      1. Pts appear toxic and septic; nephrectomy may be required

Special Populations

AIDS

  • TMP-SMX resistance is increased due to its use in PCP PNA prophylaxis
  • Most UTIs are caused by typical pathogens or common STI organisms

Pregnant Women

  • Treat all cases of asymptomatic bacteriuria

See Also

Source

Tintinalli

  1. Norris DL, Young JD. UTI. EM Clin N Am. 2008; 26:413-30.
  2. Choosing Wisely. American Urogynecologic Society. http://www.choosingwisely.org/societies/american-urogynecologic-society
  3. Huttner, A., Kowalczyk, A., Turjeman, A., Babich, T., Brossier, C., Eliakim-Raz, N., … Harbarth, S. (2018). Effect of 5-Day Nitrofurantoin vs Single-Dose Fosfomycin on Clinical Resolution of Uncomplicated Lower Urinary Tract Infection in Women: A Randomized Clinical Trial. JAMA: The Journal of the American Medical Association, 319(17), 1781–1789.