Urinary tract infection

From IDWiki

Background

  • Bacterial infection of the urinary tract, either lower (cystitis) or upper (pyelonephritis)
  • When UTI causes sepsis syndrome, often referred to as urosepsis

Microbiology

Risk Factors

  • Premenopausal women: sexual intercourse, new partner, no postcoital voiding, spermicide use, prior UTI, diabetes mellitus
  • Postmenopausal women: genitourinary atrophy/estrogen deficiency, urethral diverticulum, vaginal prolapse beyond the hymen, incontinence, postvoid residual, catheterization
  • Men: reduced prostatic secretions (older men), postvoid residual, incontinence, catheterization

Clinical Manifestations

  • Acute simple cystitis: acute UTI without signs of upper tract infection or systemic symptoms
  • Acute complicate UTI: acute UTI with fever, chills, malaise, flank pain, CVA tenderness, or (in men) pelvic/perineal pain
  • Diagnostic criteria include clinical and laboratory symptoms:
    • Two or more clinical symptoms:
      • Fever > 38ºC
      • Urinary urgency or frequency
      • Acute dysuria
      • Hypogastric pain
      • Costovertebral angle tenderness
    • One or more laboratory finding:
      • Bacteriuria (> 100,000 CFUs/mL)
      • Pyuria (>10 WBCs/HPF)

Investigations

  • Urinalysis
    • Leukocyte esterase
    • Nitrite, positive for organisms that convert nitrate to nitrite such as the Gram-negative bacteria
    • High negative predictive value if both LE and nitrite are negative
  • Urine microscopy
    • Pyuria indicated by 5-10 cells per HPF

Management

ESBLs

CREs

References

  1. ^  Dimitri M. Drekonja, Barbara Trautner, Carla Amundson, Michael Kuskowski, James R. Johnson. Effect of 7 vs 14 Days of Antibiotic Therapy on Resolution of Symptoms Among Afebrile Men With Urinary Tract Infection. JAMA. 2021;326(4):324. doi:10.1001/jama.2021.9899.