Microscopic Urine Analysis Research Articles

The iQ200 Microscopic Analyzer is valuable tool for evaluation of urinary sediment at transplanted patients

Abstract The value of urinary cytology in the diagnosis of different pathological conditions in renal transplantation is particularly important. Manual microscopic urinalysis is a high-volume procedure that currently requires significant labour. Objective: To automate the sediment evaluation and to make this more accurate using the Iris Diagnostics Automated Urine Microscopy Analyzer (iQ200). Our goal was to compare the manual and automated microscopic data to apply iQ200 in renal function monitoring. Method: The iQ200 uses digital imaging and Auto Analyte Recognition software to classify urine constituents into 12 analyte categories and quantitatively report. Results: We determined cut-off values of urine particles in every category, which correlated well with manual microscopic results. The iQ200 was more sensitive for pathological casts than manual microscopic analysis. iQ200 helped the operator to differentiate between isomorphic and dismorphic erythrocytes and between lymphocytes and granulocytes, too. Every pathological constituent could be recognized, which is very important for early recognition of renal impairment, graft rejection and urinary tract infection. Conclusions: The iQ200 system automatically classifies 12 particles, significantly reducing the need for additional sample preparation, manual microscopic review achieving a high degree of standardization in urinalysis.

Urinary sediment analysis

Urinary analysis is one of the most requested tests in the clinical laboratory. This test includes the physical, chemical and microscopic analysis of urine. This last one allows for the observation of urinary sediment (US) in search of formed elements (cellular cast, leukocytes, etc.), with different diagnostic uses. Urinary analysis can be assessed by manual or automated methods. In the laboratory diagnosis of autoimmune diseases, US analysis is mainly oriented towards the assessment of renal function in patients with lupus nephritis (LN) as this is a common clinical manifestation associated to systemic lupus erythematosus (SLE). Additionally, its value lies mainly for diagnostic criteria and evaluation of kidney injury, as well as for several damage indexes directed to patients with SLE. In the last years, several groups have sought to establish new urinary biomarkers of kidney damage in patients with SLE; however, this requires a greater number of studies to determine their true diagnostic value in this patients group.

A case of adult acute idiopathic scrotal edema

A 40-year-old man presented to a hospital emergency department with acute-onset, bilateral, painless swelling of the scrotum, which had developed progressively over the previous 12 h. He was physically well with no remarkable medical history, and was not taking any medication. He had no history of allergies or trauma (including insect bites to the genitalia), no urinary symptoms, and was not sexually active. Physical examination, assessment of erythrocyte sedimentation rate, white blood cell count, renal function panel, urine microscopic analysis, urine cultures, transillumination, and scrotal ultrasonography. Acute idiopathic scrotal edema. The patient received expectant management and treatment with an NSAID to relieve his inflammation. He was discharged from hospital and his symptoms resolved within 72 h of onset of treatment.

A case of an acute kidney injury secondary to an implanted aminoglycoside

CASE PRESENTATION An 80-year-old African American woman with a past medical history of type II diabetes mellitus, hypertension, bilateral knee replacements and peripheral vascular disease presented to the nephrology clinic for evaluation of an elevated serum creatinine. Six weeks earlier she underwent removal of a total knee prosthesis due to septic arthritis with coagulase-negative staphylococci. A vancomycin and tobramycin-impregnated cement spacer block was mixed in the operating room and implanted. Her serum creatinine concentration (sCr) was 0.9 mg/dl upon hospital discharge. Periodic laboratory studies performed at the nursing facility showed a steady increase in sCr to 1.6 mg/dl at 2 weeks and then to 3.7 mg/dl by 6 weeks (Figure 1). One week before to presentation at the nephrology clinic, she began to develop uremic symptoms including nausea, vomiting, a metallic taste, and muscle cramps. Her furosemide and lisinopril had been held for 3 weeks due to her rising serum creatinine with no improvement. Her medications on presentation were insulin, omeprazole, synthroid, metoprolol, multivitamin, clopidogrel, atorvastatin, amlodipine, warfarin and minocycline. The minocycline had been initiated after she completed a 2-week course of intravenous vancomycin. Other than the warfarin, minocycline and intravenous vancomycin, she was on no new medications. There was no documented history of hypotension and she took no non-steroidal, herbal or over-the-counter medications. Physical examination revealed that she was afebrile, her blood pressure was 124/73 mmHg and pulse was 73 beats/min. She was alert and conversant. There was pitting edema of the lower extremities to the knee, but the lungs were clear to auscultation. No rashes or joint abnormalities were noted. She did not have asterixis. She had no auditory or vestibular symptoms although these were not formally tested. Laboratory studies are shown in Table 1. Her urinalysis revealed a specific gravity of 1.013, pH of 5.0, no protein or blood, and a positive spot leukocyte esterase with 2–5 white blood count per high powered field. Urine microscopic analysis by the nephrology consult team revealed few renal tubular epithelial cells and scant granular casts without red blood cells. She remained non-oliguric during her first few days of her admission. Based upon her clinical presentation, tobramycin toxicity from her knee cement spacer was suspected. Since this diagnosis would entail surgical treatment, a transjugular renal biopsy was performed for confirmation (Figures 2, 3).

Collapsing glomerulopathy associated with inherited mitochondrial injury

The patient is an 18-month-old boy from Romania, whose parents are healthy and non-consanguineous. In October 2005, periorbital and lower extremities edema were first noted while the child was in general good conditions and without any sign of acute infectious problem. For generalized edema, he was admitted at a pediatric nephrology unit where heavy proteinuria (>10g day -1 ), with serum high cholesterol levels (>500mg per 100ml) and hypoalbuminemia (<1.5g per 100ml) were rapidly discovered. The urine microscopic analysis showed moderate microscopic hematuria, epithelial cells, and granular casts. Serum creatinine was normal. Serology was negative for hepatitis B, hepatitis C, EBV, HIV, and parvovirus B19. Complement profile was normal and tests for autoimmunity (ANA, nDNA, and ANCA) were negative. No focal neurological defects were observed. He was immediately treated with diuretics and infusions of albumin and soon started prednisone 2.3 mg kg -1 day -1 . After the first 4 weeks of therapy, his edema increased and he developed anasarca. ACE inhibitors (5 mg per 1.73 m 2 ) were added to the therapy, and a genetic approach considering major inherited diseases was adopted that excluded mutations relative to NPHS1 and NPHS2. Then, a renal biopsy was performed. As the clinical features did not improve, the patient underwent a unilateral nephrectomy and started a peritoneal dialysis program. Part of the clinical history of this patient has been described in detail elsewhere, 1 while the findings on renal biopsy and nephrectomy that are crucial for a correct differential diagnosis are described together in the next paragraph.

Benefits of the iQ200 automated urine microscopy analyser in routine urinalysis

Urine microscopic analysis is hampered by its lack in standardisation and semi-quantitative reports, resulting in limited reliability. Automation of urinalysis could overcome these problems. We compared the performance of the iQ200 with traditional microscopy and strip analysis in routine urinalysis. A total of 1482 routine samples, positive in dipstick testing, were evaluated for erythrocytes, leukocytes, casts, dysmorphic erythrocytes and bacteria using the iQ200 and traditional microscopy. The results of 320 of these samples were linked to underlying urological pathology as well as results from bacterial culturing. Analytically, the iQ200 surpasses traditional microscopy. The identification of casts and dysmorphic erythrocytes in routine samples improves when using the iQ200, although the sub-classification of casts required well-trained technicians. The auto-classification of particles was least reliable for yeast and bacterial cocci. The quantitative reports, and therefore the use of precise cut-off points allowed earlier and improved detection of urinary tract pathology. The performance of the iQ200 is equal to traditional microscopy, but it strongly improves the reliability of urinalysis by standardisation, quantitative reports and improved workflow. From a clinical point of view, renewed attention and improvement of routine urinalysis aids in the efficient detection of renal and urinary tract pathology.

Analytical performance of the Iris iQ200 automated urine microscopy analyzer

Background We evaluated the Iris iQ200 Automated Urine Microscopy Analyzer to find out if the instrument performed better than traditional visual bright field microscopy in detecting basic urine particles, as assessed against reference phase contrast microscopy. Methods The HUSLAB quality system was followed in planning and completing the evaluation process. The iQ200 instrument results from 167 mid-stream, uncentrifuged urine specimens were compared to those obtained with phase contrast reference microscopy, and to those with routine bright field microscopy. Linearity, carry-over and precision were tested according to well-established protocols. Results The iQ200 counted erythrocytes (RBC) at r = 0.894 ( R 2 = 0.799) with Automated Particle Recognition (APR) software alone and at r = 0.948 ( R 2 = 0.898) after re-classification. The performance for leukocytes (WBC) was r = 0.885 with APR and r = 0.978 after re-classification. The correlations of counting after user re-classification were r = 0.927 for squamous epithelial cells (SQEP), r = 0.856 for casts, and r = 0.706 for non-squamous epithelial cells. The iQ200 showed good linearity and precision and no carry-over was detected. Conclusions The Iris iQ200 was capable to count reliably RBC, WBC, and SQEP cells and to identify a fraction of bacteria and renal elements. Counting results equalled or exceeded that of routine bright field microscopy or earlier flow cytometric technology. The instrument eliminates manual sample preparation but requires a well-trained technologist for re-grouping of findings.

Urine sediment examination: A comparison between the manual method and the iQ200 automated urine microscopy analyzer

Background Microscopic examination of the urine sediment is an essential part in the evaluation of renal and urinary tract diseases. Traditionally, manual microscopic techniques have several methodological steps that may contribute to imprecision, inaccuracy, and are time-consuming. Recently, the iQ200 automated urine microscopy analyzer has been introduced to analyze the unspun urine, thereby improving accuracy, precision and throughput. Methods In this study, we compared its performance with manual routine slide and chamber counts. Fresh urine samples were obtained from 400 subjects. Results The reference values of white blood cells, red blood cells and squamous epithelial cells obtained by the above methods were not significant difference when the results reported as cells per high-power field. For the specimens of patients ( n = 280), a significant correlation was found when the iQ200 results of cellular elements were compared with those obtained from manual microscopy. No significant difference was found when the post-review results of the iQ200 were compared with the chamber count. However, the presence of casts, crystals, bacteria, and budding yeast needs further characterization under the microscope. Conclusions There is substantial agreement between the iQ200 and manual microscopic methods. The iQ200 provides for a rapid turnaround time.

Analytic Performance of the iQ200 Automated Urine Microscopy Analyzer and Comparison With Manual Counts Using Fuchs-Rosenthal Cell Chambers

Automated instruments that can examine urine for cells and particles have reduced the need for labor-intensive manual microscopy. We evaluated the performance of the Iris iQ200 Automated Urine Microscopy Analyzer (Iris Diagnostics, Chatsworth, CA) and compared results with manual cell and particle counts using Fuchs-Rosenthal counting chambers. Within-run imprecision (coefficient of variation) of the iQ200 for urine samples ranged from 3.0% to 45% for RBC counts between 1,029 and 3 × 106 cells/L, 3.4% to 40% for WBC counts between 1,006 and 4 × 106 cells/L, and 8.9% to 35% for epithelial cell counts between 93 and 4 × 106 cells/L. Between-run imprecision was 3.3% at 1,017 × 106 cells/L and 19.2% at 28 × 106 cells/L. There was good agreement between the iQ200 and manual cell counts (r ≥ 0.94); however, the iQ200 produced lower results based on slopes of 0.92 (RBC count), 0.81 (WBC count), and 0.94 (epithelial cell counts). The iQ200 has satisfactory performance and correlates well with manual cell counts. Most urine samples containing RBCs, WBCs, and epithelial cells can be reported without review of captured images.

Analytic Performance of the iQ200 Automated Urine Microscopy Analyzer and Comparison With Manual Counts Using Fuchs-Rosenthal Cell Chambers

Automated instruments that can examine urine for cells and particles have reduced the need for labor-intensive manual microscopy. We evaluated the performance of the Iris iQ200 Automated Urine Microscopy Analyzer (Iris Diagnostics, Chatsworth, CA) and compared results with manual cell and particle counts using Fuchs-Rosenthal counting chambers. Within-run imprecision (coefficient of variation) of the iQ200 for urine samples ranged from 3.0% to 45% for RBC counts between 1,029 and 3 x 10(6) cells/L, 3.4% to 40% for WBC counts between 1,006 and 4 x 10(6) cells/L, and 8.9% to 35% for epithelial cell counts between 93 and 4 x 10(6) cells/L. Between-run imprecision was 3.3% at 1,017 x 10(6) cells/L and 19.2% at 28 x 10(6) cells/L. There was good agreement between the iQ200 and manual cell counts (r > or = 0.94); however; the iQ200 produced lower results based on slopes of 0.92 (RBC count), 0.81 (WBC count), and 0.94 (epithelial cell counts). The iQ200 has satisfactory performance and correlates well with manual cell counts. Most urine samples containing RBCs, WBCs, and epithelial cells can be reported without review of captured images.

Cystatin C is a more sensitive marker than creatinine for the estimation of GFR in type 2 diabetic patients

Glomerular filtration rate (GFR) is the best overall index of renal function in health and disease. Inulin and 51Cr-EDTA plasma clearances are considered the gold standard methods for estimating GFR. Unfortunately, these methods require specialized technical personnel over a period of several hours and high costs. In clinical practice, serum creatinine is the most widely used index for the noninvasive assessment of GFR. Despite its specificity, serum creatinine demonstrates an inadequate sensitivity, particularly in the early stages of renal impairment. Recently, cystatin C, a low molecular mass plasma protein freely filtered through the glomerulus and almost completely reabsorbed and catabolized by tubular cells, has been proposed as a new and very sensitive serum marker of changes in GFR. This study was designed to test whether serum cystatin C can replace serum creatinine for the early assessment of nephropathy in patients with type 2 diabetes. The study was performed on 52 Caucasian type 2 diabetic patients. Patients with an abnormal albumin excretion rate (AER) were carefully examined to rule out non-diabetic renal diseases by ultrasonography, urine bacteriology, microscopic urine analysis, and kidney biopsy. Serum creatinine, serum cystatin C, AER, serum lipids, and glycosylated hemoglobin (HbA1c) were measured. GFR was estimated by the plasma clearance of 51Cr-EDTA. In addition the Cockcroft and Gault formula (Cockcroft and Gault estimated GFR) was calculated. Cystatin C serum concentration progressively increased as GFR decreased. The overall relationship between the reciprocal cystatin C and GFR was significantly stronger (r = 0.84) than those between serum creatinine and GFR (r = 0.65) and between Cockcroft and Gault estimated GFR and GFR (r = 0.70). As GFR decreased from 120 to 20 mL/min/1.73 m2, cystatin C increased more significantly that serum creatinine, giving a stronger signal in comparison to that of creatinine over the range of the measured GFR. The maximum diagnostic accuracy of serum cystatin C (90%) was significantly better than those of serum creatinine (77%) and Cockcroft and Gault estimated GFR (85%) in discriminating between type 2 diabetic patients with normal GFR (>80 mL/min per 1.73 m2) and those with reduced GFR (<80 mL/min/1.73 m2). In particular, the cystatin C cut-off limit of 0.93 mg/L corresponded to a false-positive rate of 7.7% and to a false-negative rate of 1.9%; the serum creatinine cut-off limit of 87.5 micromol/L corresponded to a false-positive rate of 5.8% and to a false-negative rate of 17.0%. Cystatin C may be considered as an alternative and more accurate serum marker than serum creatinine or the Cockcroft and Gault estimated GFR in discriminating type 2 diabetic patients with reduced GFR from those with normal GFR.

Case Study: Renal Disease in Type 1 Diabetes

C.M. is a 27-year-old woman with type 1 diabetes diagnosed at age 14 when she presented with diabetic ketoacidosis. Her initial insulin treatment was complicated by poor glycemic control, frequent hypoglycemia, and weight gain. Two years ago, she developed hypertension, which was treated with hydrochlorthiazide, 25 mg daily. At that time, she was noted to have nonproliferative diabetic retinopathy. Blood urea nitrogen (BUN) was 23 mg/dl, creatinine was 0.9 mg/dl, and dipstick urinalysis was negative for protein. She now presents with accelerated hypertension (172/108 mmHg) and pitting edema of the legs to the level of the knees. Urinalysis reveals 3+ protein and 2+ blood. Urine microscopic analysis reveals hyalin and red blood cell casts. BUN is 37 mg/dl; creatinine is 1.5 mg/dl; and 24-h urine reveals 9.7 g of protein. …

Encuesta sobre los métodos de diagnóstico microbiológico de la infección urinaria

The urinary tract infection (UTI), a highly prevalent disease, must be confirmed by microbiological diagnosis. The Clinical Microbiology Committee of the Chilean Infectious Diseases Society did a retrospective survey in order to know the methodology and diagnostic criteria employed for UTI microbiological diagnosis by a representative number of clinical laboratories. The information about 49.632 urine cultures collected was obtained from fifteen public hospitals and private laboratories. All the laboratories employed the same criteria for UTI diagnosis: a microbial count > 100.000 cfu/ml. We couldn't analize lesser counts, (data was not available neither for sample collecting methods, concomitant microscopic urine analysis -urinary sediment- nor clinical symptoms). Utilizing this diagnostic criteria the yield varied among 2.3% in men and 33% in women, with more dispersed rates in children. Only the 13% of institutions processed the urine samples knowing the time transcurred since the sample collection. All the laboratories employed the same criteria to consider as contaminated a culture with: > 3 microorganisms; some of them registered 17% of contamination. Although this survey was retrospectively done diminishing the quality of the situation diagnosis, it motivated the Clinical Microbiology Advisory Committee to prepare Guidelines for the Microbiological Diagnosis of UTI.

Urine microscopic analysis--an art abandoned by nephrologists?

Urine microscopic analysis--an art abandoned by nephrologists?

Urine analysis. Report on the Workshop Conference of the German Society for Clinical Chemistry and the Society of Nephrology in Würzburg, October 25-26, 1985.

In an expert workshop conference amongst 45 members of the Society of Nephrology and the German Society for Clinical Chemistry, topical aspects and problems of urine analysis were presented and discussed. The present report summarizes the most significant results, points arising in discussion, and recommendations for test strip analysis, microscopic urine analysis, determination and differentiation of proteinuria and urine enzymology.