Enhancing the Detection of Dysmorphic Red Blood Cells and Renal Tubular Epithelial Cells with a Modified Urinalysis Protocol

Abstract

Urinary sediment is used to evaluate patients with possible urinary tract diseases. Currently, numerous protocols are applied to detect dysmorphic red blood cells (RBCs) and renal tubular epithelial cells (RTECs) in urinary sediment. However, distinct protocols are used by nephrologists and medical technologists for specimen concentration and observation, which leads to major discrepancies in the differential counts of formed elements such as dysmorphic RBCs and RTECs and might interfere with an accurate clinical diagnosis. To resolve these problems, we first tested a modified urinalysis protocol with an increased relative centrifuge force and concentration factor in 20 biopsy-confirmed glomerulonephritis patients with haematuria. We successfully improved the recovery ratio of dysmorphic RBCs in clinical specimens from 34.7% to 42.0% (P < 0.001). Furthermore, we confirmed the correlation between counts by the modified urinary protocol and Sysmex UF-1000i urinary flow cytometer (r ≥ 0.898, P < 0.001). A total of 28 types of isomorphic and dysmorphic RBCs were detected using a bright field microscope, with results comparable to those using a standard phase contrast microscope. Finally, we applied Sternheimer stain to enhance the contrast of RTECs in the urinary sediments. We concluded that this modified urinalysis protocol significantly enhanced the quality of urinalysis.

Small Red Blood Cell Fraction on the UF-1000i Urine Analyzer as a Screening Tool to Detect Dysmorphic Red Blood Cells for Diagnosing Glomerulonephritis

“…However, PCM is a time-consuming, labor-intensive, and insufficiently precise process that requires expert skills and knowledge, and is also influenced by the differences in sample preparation, such as amount of sample, centrifugation, and technician ability. Consequently, large inter-laboratory differences in the specificity and sensitivity of PCM have been reported [78].…”

The Concordance of Dysmorphic Erythrocyte and Cast Erythrocyte Examination using Flowcitometry, Low Condenser Light Microscope, and Phase Contrast Microscope in Children with Glomerular Hematuria

“…These erythrocytes are smaller in size and have smaller cytoplasmic protrusions or cell fragments 1,15,16,17 . From LLCM examination result by 3 readers, dysmorphic erythrocytes were positive in 32 samples (80%) and negative in 8 samples (20%), while the dysmorphic erythrocytes from PCM was slightly more, positive in 34 samples (85%) and negative in 6 sample (15%).…”

A Microfluidic Detection System for Bladder Cancer Tumor Cells

“…However, urine cytology still contributes to disease diagnosis as a classic, inexpensive, and rapid detection method [25]. Here, the proposed system detected the sample at a speed of 2 mL/h, and according to CLSI Urinalysis approved guidelines, the detection time for a concentrated 1 mL sample was only 0.5 h [26]. As a non-invasive in vitro biopsy method, urine cytology takes significantly less time than the current histopathological examination method [27] and is less damaging to patients than imaging methods such as imaging and cystoscopy.…”