Spectrum: Local Antimicrobial Stewardship, for CHEO-OCTC

Urine Specimens

A urine analysis and a urine microscopy are indispensable to diagnose a urinary tract infection. If these are negative, the likelihood of a urinary tract infection are very low and the diagnosis should be reconsidered.

Clinical Criteria for Suspected UTI

Include:

  • Fever more than 24 hours

  • Ill appearing

  • Suprapubic tenderness

And when age appropriate:

  • Dysuria,

  • Urinary frequency

  • Hematuria

  • Abdominal pain

  • Back pain

  • New daytime incontinence

Laboratory Criteria for Suspected UTI

Include:

  • Urinalysis (leukocyte esterase or nitrite positive)

AND/OR

  • Pyuria on urine microscopy (greater than 5 WBC/hpf).

Note

Urine should not sit at room temperature for more than 30 minutes before being cultured and should be transported to the laboratory within 30 to 60 minutes of collection, otherwise there is a high probability of bacterial growth of contaminants.

Reassess any suspected UTI after urine microscopy and urine analysis and culture results are available.

Two or more species of bacteria in a urine culture usually indicates contamination.

Specimens with < 50 to 100 X 10⁶/L bacteria are probably contaminants and the diagnosis should be reassessed.