Squamous cells as predictors of bacterial contamination in urine samples.
OBJECTIVE
To determine whether squamous cells in urine indicate bacterial contamination.


METHODS
We prospectively studied 105 consecutive women who presented to the emergency department with symptoms suggestive of a urinary tract infection. Two urine samples were collected from each woman, a midstream clean-catch (MSCC) sample and a catheterized (CATH) sample. Microscopic urinalyses to assess for squamous cells and urine cultures to assess for bacterial contamination were performed on all samples. Bacterial contamination was defined as growth of fewer than 10,000 colonies of a single species per milliliter or growth of three or more species of commensal bacteria (mixed flora) in a urine sample.


RESULTS
Squamous cells were found in 99 of 105 CATH samples (94%); however, no CATH samples had bacterial contamination. Squamous cells were found in 101 of 105 MSCC samples (96%); however, only 22 MSCC samples (21%) had bacterial contamination.


CONCLUSIONS
The presence of squamous cells in CATH urine samples obtained from women is not indicative of bacterial contamination. The presence of squamous cells in MSCC urine samples obtained from women also is not a good indicator, with an overall predictive value for bacterial contamination of 21%.
Walter
F G
FG
Department of Emergency Medicine, Valley Medical Center, Fresno, CA, USA.
Gibly
R L
RL
Knopp
R K
RK
Roe
D J
DJ
D000293:Adolescent; D000328:Adult; D000368:Aged; D001431:Bacteriological Techniques; D001437:Bacteriuria / Q000175:diagnosis* / Q000382:microbiology; D002452:Cell Count; D015169:Colony Count, Microbial; D004847:Epithelial Cells / Q000166:cytology* / Q000382:microbiology; D005260:Female; D006801:Humans; D008875:Middle Aged; D011237:Predictive Value of Tests; D011446:Prospective Studies; D013048:Specimen Handling; D014546:Urinary Catheterization; D014552:Urinary Tract Infections / Q000175:diagnosis* / Q000382:microbiology; D014556:Urine / Q000166:cytology* / Q000382:microbiology*