Change to automated analyser for urine microbiological investigation

 

We are proposing from 9^th October 2006 to replace urine microscopy with a new automated technique using flow cytometry (UF-100 Biostat) to count the number of white and red blood cells, epithelial cells, casts and bacteria.  This technique is approximately four times more sensitive than microscopy and can confidently identify those samples that do not require culture.  We will continue to culture all urines in immunosuppressed and pregnant patients and from suprapubic aspirates.

 

You will notice the following changes:

 

1. An absolute count of the number of white cells and red blood cells will be reported.
2. Because of the increased sensitivity of the technique the counts will be higher than those currently given.  A new reference range will be provided to assist in determining whether the value is raised.
3. Samples with counts within the normal range by flow cytometry will be reported as negative on the day of receipt.  Those with elevated counts will be processed as before.
4. To help prevent sample deterioration urines MUST now be submitted in boric acid containers (red top universal), except for low volumes where plain universals can be used.

 

The proposed changes will provide benefits to all as the technique is more accurate than microscopy and there will be a more rapid turnaround of negative results which account for about 50% of the samples received