The effect of specimen processing delay on borate urine preservation.
OBJECTIVE
To investigate the effect on urine culture results and their clinical interpretation of delaying the processing of urine samples in which boric acid had been used as a preservative.


METHODS
792 mid-stream specimens of urine from patients attending their general practitioner were received in borate containing plastic jars. The specimens were cultured upon receipt, stored at room temperature, and then recultured the following morning.


RESULTS
After overnight delayed culture, the results were altered in 16% of samples and the clinical interpretation of these findings differed in 8% of specimens. In 28 samples (3.5%) the bacterium isolated on initial culture was not the same as that obtained by culture after overnight storage.


CONCLUSIONS
Boric acid urine preservation used for overnight delayed processing of samples is associated with a significant alteration in culture results and the attendant clinical interpretation of such specimens. Rapid transportation/processing of urine specimens must remain the optimum procedure.
Department of Clinical Microbiology, Western General Hospital, Edinburgh, UK.
T
T
Gillespie
J
J
Fewster
R G
RG
Masterton
D001419:Bacteria / Q000187:drug effects* / Q000254:growth & development; D001437:Bacteriuria / Q000175:diagnosis* / Q000382:microbiology; D001888:Boric Acids / Q000494:pharmacology*; D005260:Female; D006801:Humans; D008297:Male; D011310:Preservatives, Pharmaceutical / Q000494:pharmacology*; D011446:Prospective Studies; D013048:Specimen Handling / Q000379:methods; D013997:Time Factors; D014021:Tissue Preservation / Q000379:methods*
D001888:Boric Acids; D011310:Preservatives, Pharmaceutical; C032688:boric acid