Lab

Urine Culture

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Urine Culture

  • Collection
  1. Sterile Methods
    1. Catheterized Urine
    2. Suprapubic Tap
  2. Clean Methods
    1. Clean Catch Urine Collection
    2. Bag Urine Collection
  • Specimen handling
  1. Volume: 5 ml (0.2 ml minimum)
  2. First morning void is ideal specimen
  3. Deliver to lab or refrigerate within 30 minutes
  • Interpretation
  • Clean Voided Specimen
  1. Normal: <10,000 organisms per ml
  2. Urinary Tract Infection
    1. Boys
      1. Organisms >10,000 per ml suggests UTI likely
    2. Girls
      1. Organisms >100,000 per ml suggests UTI
        1. Three specimens: 95% probability of UTI
        2. Two specimens: 90% probability of UTI
        3. One specimen: 80% probability of UTI
      2. Organisms >10,000 per ml needs repeat Urine Culture
  • Interpretation
  • Transurethral Catheterization
  1. Normal: <1,000 organisms per ml
  2. Urinary Tract Infection
    1. Organisms >10,000 per ml suggests UTI
    2. Organisms >1,000 per ml needs repeat Urine Culture
  • Interpretation
  • Suprapubic aspiration in infants
  1. Gram Negative Bacilli: any number suggests UTI (99%)
  2. Gram Positive Cocci: >1-2,000 suggests UTI (99%)
  • References
  1. Hellerstein (1982) Pediatr Infect Dis 1:271-81 [PubMed]