Diagnostic Characteristics of Urinary Red Blood Cell Distribution Incorporated in UF-5000 for Differentiation of Glomerular and Non-Glomerular Hematuria

Abstract

Background: Automated urine sediment analysis has been developed to address the limitations of microscopic examination of dysmorphic red blood cells (RBCs). We evaluated the urinary RBC distribution (URD) parameter of a recently launched automated urinary flow cytometry analyzer, UF-5000 (Sysmex, Kobe, Japan), to differentiate glomerular hematuria (GH) from non-GH (NGH).Methods: Samples submitted for urine sediment analysis from patients with hematuria ( > 20 RBCs/μL) were divided into derivation (N = 156; 101 GH, 55 NGH) and validation cohorts (N = 107; 60 GH, 47 NGH). The clinical diagnosis of GH or NGH was established based on clinical data review. Differences in UF-5000 parameters (URD, small RBC, lysed RBC, RBC-P70FSC, RBC-SF-FSC-W, mean forward-scattered light, and mean side-scattered light) between GH and NGH, and areas under the ROC curves (AUC) were analyzed in the derivation cohort. The derived ideal cut-off value was evaluated in the validation cohort. We applied the Kitasato criteria to compare the diagnostic performance.Results: URD (%), differed significantly between GH and NGH (P < 0.001) in the two cohorts. The AUC of URD was 0.814 and 0.806 in the derivation and validation cohorts, respectively. Using a cut-off of > 20.1%, the sensitivity was 99.0%/89.4% and the specificity was 50.9%/63.3% in the derivation/validation cohort. When the Kitasato criteria were applied, the sensitivity and specificity were 80.2% and 52.7%, respectively.Conclusions: URD is a rapid, objective, and quantitative measure that can be used to differentiate GH and NGH.

How to define and assess the clinically significant causes of hematuria in childhood

“…Flow cytometers have also been used to differentiate the glomerular and non-glomerular origin of hematuria, albeit with conflicting results [ 19 ]. While the sensitivity of the method has been found to be low for differentiation in previous studies, newer devices appear to be more accurate in this regard [ 20 ]. Nonetheless, extensive clinical trials are still lacking and the final assessment should be made by an experienced and knowledgeable medical eye [ 19 , 20 ].…”

Performance analysis of urine formed element analyzer EH-2090 was found to have good accuracy in detecting RBCs and WBCs when compared to manual microscopic

“…The screening performance of urine testing for UTIs is widely recognized ( 18 - 21 ). In addition, automated urine sediment analyzers have been used to differentiate between glomerular hematuria (GH) and non-glomerular hematuria (NGH) ( 22 ). Urine testing can also be predictive of suspected uroepithelial cancer ( 23 ).…”

The application of new complex indicators in the detection of urine

“…Urine RBC counts can be measured using automated urine sediment analyzers [ 4 ]. A previous study suggested that the determination of urinary RBC distribution with an automated analyzer and analysis of the distribution curves may be a more reliable measure of erythrocyte morphology [ 18 ]. Renal biopsy, the gold standard for the diagnosis of kidney diseases, can be used to verify the sources of urinary RBCs, and the count and morphology of urinary RBCs can, in turn, provide important information on patients’ renal pathological changes [ 19 ].…”