Comparative assessment of phase contrast microscopy and Coulter counter measurements in localising the site of haematuria.
Haematuria is a common diagnostic problem in clinical practice and is seen in a large number of renal, urological and systemic disorders. The routine use of dipstick methods has increased the frequency of detection of microscopic haematuria. It is desirable to develop a simple, non-invasive, easily reproducible, quantitative technique that would help to determine the site of bleeding and thereby direct the patient either to the nephrologist or to the urologist. This study compares the accuracy of phase contrast microscopy with Coulter counter measurement of red cell distribution volumes as a means of distinguishing glomerular haematuria from non-glomerular haematuria. Of 20 patients with biopsy-proven glomerulonephritis, 13 (65%) were correctly identified by phase contrast microscopy and 19 (95%) by the Coulter counter method. In 18 patients with pathological conditions affecting the lower urinary tract phase contrast microscopy was correct in 6 (33%) and Coulter counter measurement in 17 (94%). Coulter counter measurement is the simpler and more accurate method of screening for the source of haematuria, but is inaccurate when the red cell count in the urine is less than 0.02 x 10(12).
Naicker
S
S
Department of Medicine, King Edward VIII Hospital, Durban.
Poovalingam
V
V
Mlisana
K
K
Christopher
N
N
Nadesan
D
D
Seedat
Y K
YK
D000293:Adolescent; D000328:Adult; D000368:Aged; D004906:Erythrocyte Count / Q000379:methods*; D005260:Female; D006417:Hematuria / Q000175:diagnosis*; D006801:Humans; D008297:Male; D008858:Microscopy, Phase-Contrast; D008875:Middle Aged