Intended for healthcare professionals

Practice Guidelines

Early identification and management of chronic kidney disease: summary of NICE guidance

BMJ 2008; 337 doi: (Published 29 September 2008) Cite this as: BMJ 2008;337:a1530

Definition of Non Visible Haematuria

Recent guidelines have suggested using dipstick urine testing to
define non visible haematuria rather than microscopy on the basis that
“community based urine samples sent for microscopy have a significant
false negative rate; the procedure is more labour intensive, and adds
little to establishing the diagnosis of haematuria”. 1,2

However abnormal red cell counts are frequently reported on samples
sent for culture in cases of suspected UTI.

Recently our local microbiology laboratory has changed from using
direct microscopy to flow cytometry. This has led to a great increase in
the number of samples being reported positive for red cells– a survey in
my practice revealed from 17% to 33% borderline and from 3% to 27%

Flow cytometry red cell count

NORMAL                  <50      12     40%
BORDERLINE            50-100      10     33%
ABNORMAL              > 100        8     27%
TOTAL                             30   100%
 Direct microscopy red cell count
NORMAL                   >10      24     80%
BORDERLINE            10-50        5     17%
ABNORMAL                   50-200        0      
ABNORMAL              >200        1       3%
TOTAL                              30   100% 

In addition, poor correlation between urine dipstick testing and flow
cytometry red cell counts has been documented.3

Whilst the guidelines deal well with haematuria found on dipstick
testing, primary care practitioners need guidance on how to manage
abnormal red cell counts found incidentally on samples sent for culture,
particularly with flow cytometry results.

Des Ling general practitioner, Queens Avenue Surgery, Dorchester DT1



3. Michel R. Langlois, Joris R. Delanghe, Sophia R. Steyaert, Karel
C. Everaert, and Marc L. De Buyzere Automated Flow Cytometry Compared with
an Automated Dipstick Reader for Urinalysis Clin Chem 1999; 45: 118-122

Competing interests:
None declared

Competing interests: NORMAL &lt;50 12 40%BORDERLINE 50-100 10 33%ABNORMAL &gt; 100 8 27%________TOTAL 30 100% Direct microscopy red cell countNORMAL &gt;10 24 80%BORDERLINE 10-50 5 17%ABNORMAL 50-200 0 ABNORMAL &gt;200 1 3%________ TOTAL 30 100%

02 December 2008
Des Ling
General Practitioner
Queens Avenue Surgery, Dorchester