Tests
1st tests to order
urinalysis
Test
Performed on clean catch midstream dipstick specimen.
Indicated if diagnosis is uncertain, or if complicating features are present.[37]
The presence of hematuria combined with a positive dipstick test for nitrites has a high diagnostic utility for ruling in the diagnosis of urinary tract infection.[33] Do not define microhematuria by positive dipstick testing alone. Only define microhematuria using urine microscopy.[35][36]
Result
positive for leukocyte esterase, nitrites, and hemoglobin
urine microscopy
Test
Performed on clean catch midstream dipstick specimen.
Greater than 10 WBC per high-powered field of an unspun urine is considered diagnostic.
Microscopic detection of red blood cells instead of hemoglobin excludes false-positive urinalysis results from myoglobin or hemoglobin. Only define microhematuria using urine microscopy: three or more red blood cells per high-powered field on microscopy of a properly collected urinary specimen.[35][36] Radiographic and cystoscopic evaluation is unnecessary in the absence of microscopically confirmed microhematuria.[35]
Epithelial cells suggest a contaminated specimen.
Result
presence of red blood cells, white blood cells, and bacteria
urine culture with sensitivity
Test
Performed on clean catch midstream dipstick specimen.
Greater than 10³ colony-forming units/mL of urine is the gold standard of diagnosis. Many laboratories use the cutoff of only 10⁴ colony-forming units/mL of urine. For a suprapubic aspirate, the cutoff of only 10² colony-forming units/mL of urine should be applied.[38]
Most specific and sensitive. Positive urine culture identifies infecting organism. Enables modification of treatment based on antibiotic susceptibility.
Result
identification of infecting organism
Tests to consider
pregnancy test
Test
Screened before treatment if applicable.
Result
positive
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