Biochemia Medica, Vol. 18 No. 2, 2008.
Professional paper
Flow cytometric differentiation of the origin of hematuria using fluorescent antiglycophorin antibody
Marija Miloš
orcid.org/0000-0002-0248-4278
; Clinical Institute of Laboratory Diagnosis, Zagreb University School of Medicine and Clinical Hospital Center, Zagreb, Croatia
Gordana Boršo
; Department of Internal Medicine, Unit of Nephrology and Hypertension, Zagreb University School of Medicine and Clinical Hospital Center, Zagreb, Croatia
Dubravka Čvorišćec
; Clinical Institute of Laboratory Diagnosis, Zagreb University School of Medicine and Clinical Hospital Center, Zagreb, Croatia
Abstract
Background: Glomerular and urinary tract origins of hematuria are differentiated on the basis of urinary red cell morphology. Glomerular erythro-cytes are distorted and are smaller than erythrocytes from the lower urinary tract. In this study, we investigated the possibility of flow cytometric differentiation of the origin of hematuria using phycoerythrin-conjugated antibody against glycophorin A, by measuring parameters dependent on morphologic characteristics of urinary erythrocytes.
Materials and methods: Fresh urine samples from 31 patients with glomerular disease and 31 patients with urological disease were analyzed on the flow cytometer FACScan (Becton Dickinson, San Jose, USA). Erythrocytes were distinguished from other particles with similar size in urine by staining with phycoerythrin-conjugated antibody against glycophorin A. The intensity of forward scattered light (FSC) and side scattered light (SSC) of the erythrocytes were measured as indicators of red cell size and shape, respectively. Also, the SSC/FSC ratio was calculated.
Results: A statistically significant difference in FSC (P < 0.001), SSC (P = 0.016) and SSC/FSC ratio (P < 0.001) values between two groups of patients were found. According to ROC analysis (Receiver Operating Characteristic) the following results were obtained in distinguishing the origin of hematuria: for FSC (cut-off value for glomerular hematuria: FSC ≤ 49), diagnostic sensitivity 90.3% and specificity 83.9%; for SSC (cut-off value for glomerular hematuria: SSC > 73), diagnostic sensitivity 83.9% and specificity 61.3%; for SSC/FSC ratio (cut-off value for glomerular hematuria: SSC/FSC > 2.42), diagnostic sensitivity 83.9% and specificity 90.3%.
Conclusion: The described flow cytometry analysis is a simple, automated method that can be used to establish distinction between glomerular and non-glomerular bleeding. Compared to the method of urinary red cell morphology examination, it yields more objective and reliable informations and allows directing of patients to urologic or nephrologic treatment.
Keywords
glomerular hematuria; non-glomerular hematuria; flow cytometry
Hrčak ID:
24159
URI
Publication date:
5.6.2008.
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