A new automated system for urine analysis: a simple, cost-effective and reliable method for distinguishing between glomerular and nonglomerular sources of haematuria

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

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.

Isomorphic red blood cells using automated urine flow cytometry is a reliable method in diagnosis of bladder cancer

BACKGROUND

We aimed to identify patients with a chief complaint of hematuria who could safely avoid unnecessary radiation and instrumentation in the diagnosis of bladder cancer (BC), using automated urine flow cytometry to detect isomorphic red blood cells (RBCs) in urine.

METHODS

We acquired urine samples from 134 patients over the age of 35 years with a chief complaint of hematuria and a positive urine occult blood test or microhematuria. The data were analyzed using the UF-1000i (®) (Sysmex Co., Ltd., Kobe, Japan) automated urine flow cytometer to determine RBC morphology, which was classified as isomorphic or dysmorphic. The patients were divided into two groups (BC versus non-BC) for statistical analysis. Multivariate logistic regression analysis was used to determine the predictive value of flow cytometry versus urine cytology, the bladder tumor antigen test, occult blood in urine test, and microhematuria test.

RESULTS

BC was confirmed in 26 of 134 patients (19.4 %). The area under the curve for RBC count using the automated urine flow cytometer was 0.94, representing the highest reference value obtained in this study. Isomorphic RBCs were detected in all patients in the BC group. On multivariate logistic regression analysis, only isomorphic RBC morphology was significantly predictive for BC (p < 0.001). Analytical parameters such as sensitivity, specificity, positive predictive value, and negative predictive value of isomorphic RBCs in urine were 100.0, 91.7, 74.3, and 100.0 %, respectively.

CONCLUSION

Detection of urinary isomorphic RBCs using automated urine flow cytometry is a reliable method in the diagnosis of BC with hematuria.

A new method to evaluate spontaneous platelet aggregation in type 2 diabetes by Cellfacts

BACKGROUND

The alterations in the functional activities of platelets in diabetes produce an increase of spontaneous platelet aggregation (SPA) and release of platelet-derived microparticles. Platelet-derived microparticles are shed from platelets during activation by high shear stress, collagen and certain agonists. Although the physiologic role of microparticles has been difficult to assess, the characterization of their biological activity is of interest in view of a possible role in hemostasis and coagulation and their reported involvement in thrombotic disease.

METHODS

We propose a new, simple method to evaluate spontaneous platelet aggregation and release of platelet-derived microparticles by the Cellfacts analyser (Microbial System Limited (MSL), Coventry, England) that uses electrical sensing flow impedance determination to detect the size particles and the cells in a conductive fluid. Platelet-rich plasma (PRP) from type 2 diabetes was employed for this study. The importance of platelet-activating factor (PAF) on spontaneous platelet aggregation was evaluated and the effect of vitamin E and WEB 2086-BS, an antagonist of platelet-activating factor, was measured.

RESULTS AND CONCLUSIONS

Data presented show that Cellfacts could be an easy and fast instrument to check the state of platelets in patients with alterations in the functionality of platelets, and to follow the effect of pharmacological therapy on spontaneous platelet aggregation and the release of platelet-derived microparticles.

Comparison of red blood cell volume distribution curves and phase-contrast microscopy in localization of the origin of hematuria

OBJECTIVES

To determine the ability, reliability, and accuracy of urinary red blood cell volume distribution curves obtained with the use of an autoanalyzer to identify the origin of isolated microscopic hematuria and compare the results with those obtained with phase-contrast microscopy (PCM).

METHODS

A prospective evaluation was performed in 45 patients with glomerular or nonglomerular microhematuria detected by urinalysis, PCM, radiologic evaluation, endoscopy, and, sometimes, renal biopsy. Urine samples were analyzed in an electronic particle-size analyzer, and the tests were repeated to assess reliability. The kappa correlation coefficient was used to assess reliability and to compare the results with the final diagnosis and with those obtained with PCM.

RESULTS

Of the 28 patients who had a single definite cause of hematuria, 16 had glomerular bleeding and 12 nonglomerular bleeding. The origin of hematuria was correctly identified by the autoanalyzer in 60.7% of cases. A statistically significant correlation was found with the final diagnosis (kappa = 0.433, P = 0.048). The reliability was excellent (kappa = 0.917, P <0.0001). Of 16 patients with glomerulonephritis, 10 (62.5%) were correctly identified by PCM and 14 (87.5%) by the autoanalyzer. In 12 patients with nonglomerular bleeding, PCM was accurate in 7 (58%) and the autoanalyzer in 3 (25%). The results were statistically correlated with the findings of PCM (kappa = 0.327, P <0.00001).

CONCLUSIONS

The use of an autoanalyzer is easy, reproducible, and noninvasive. It provides reliable information to orient the diagnosis toward glomerular or nonglomerular bleeding. It is as accurate as PCM for screening for the source of hematuria.