Manual Urine Microscopy Versus Automated Urine Analyzer Microscopy in Patients with Acute Kidney Injury

Abstract

This study provides evidence of the importance of performing a manual microscopic examination of urine sediment in patients with AKI. Further studies are needed to assess whether manual microscopy provides prognostic implications regarding renal recovery, hemodialysis dependency, and mortality.

Automated urinalysis combining physicochemical analysis, on-board centrifugation, and digital imaging in one system: A multicenter performance evaluation of the cobas 6500 urine work area

“…The present multicenter study demonstrates that automated urinalysis can be performed at high throughput in a precise and accurate manner across multiple sites and for all test parameters. The new cobas 6500 system enables reliable detection of bacteria, yeast, and pathological casts, and consistently shows higher sensitivity (with similar specificity) versus that of the iQ200 analyzer, as demonstrated in the present study and in previous reports [11,37]. Thus, the cobas 6500 system meets the sensitivity criteria for these parameters, which have been postulated to be at least 80% [37].…”

“…Thus, the cobas 6500 system meets the sensitivity criteria for these parameters, which have been postulated to be at least 80% [37]. The high sensitivity for pathological casts is particularly important for the early detection of acute kidney injury [11]. The cobas 6500 system also demonstrated excellent precision across laboratories, with within-individual CVs (CVi) for 21-day intermediate precision consistently below 10%.…”

“…Urinalysis is a very common technique used in clinical practice, providing crucial information on the functioning of the kidneys and other organ systems, and aiding clinical decision-making in various diseases, such as diabetes, glomerulonephritis, and suspected urinary tract infections (UTIs) [[1], [2], [3], [4], [5], [6], [7], [8], [9], [10], [11], [12], [13]]. Routine urinalysis involves a two-step approach after initial macroscopic examination, consisting of both physicochemical evaluation and microscopic examination of urine sediment to differentiate and quantify clinically relevant urine particles [[14], [15], [16], [17], [18]].…”

“…The increased throughput of these instruments over manual methods enables the reliable and rapid screening of urine samples with reduced labor demands on laboratory staff, thereby improving efficiency and cost-effectiveness [36,37]. Additionally, these instruments can improve reliability and precision by eliminating inter-operator variability, and require a low sample volume [[2], [3], [4], [5], [6], [7], [8], [9], [10], [11], [12]]. Two broad techniques have been developed for automated urine sediment analysis: urinary flow cytometry [33,[38], [39], [40]] and image-based microscopy using a built-in camera [[41], [42], [43]].…”

Acute kidney injury 2016: diagnosis and diagnostic workup

“…It is not utilized very often in the ICU predominantly because it is operator dependent and requires training and experience. When done properly, the presence of red cell casts or dysmorphic red cells supports the diagnosis of glomerular disease [ 54 – 58 ]. Urine microscopy may also help to diagnose septic AKI and predict worsening renal function.…”