Urinary tract infection

Definition

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

Etiology

• Typical organisms include:
  • E. coli
  • S. saprophicitus

Investigations

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