Urinary tract infection

Background

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

Microbiology

• Ascending genitourinary infection
  • E. coli
  • S. saprophicitus
  • Enterococcus faecalis
• Bacteremia
  • Staphylococcus aureus
  • Candida species

Clinical Manifestations

• 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 has high NPV (~100%) if negative for leukocyst esterase and nitrites