Urine Particle Research Articles

Dependence of ultrasound decorrelation on urine scatter particle concentration for a non-invasive diagnosis of bladder outlet obstruction.

To develop a non-invasive method to diagnose Bladder Outlet Obstruction (BOO) based on decorrelation of subsequently acquired UltraSound (US) data of urinary flow, we studied the influence of scatter particle concentration on the decorrelation process in urethra models using both aqueous solutions of scattering particles and urine samples. A tissue mimicking urethra model made from PolyVinyl Alcohol (PVA) solution was infused with seven aqueous solutions containing different particle concentrations at a constant flow rate value of 10 ml/sec. The average correlation coefficients between subsequent US images were calculated and plotted as a function of particle concentration. This procedure was also applied to stepwise diluted urine samples from nine healthy volunteers. An inversely exponential curve was fitted to the experimental data to estimate the scatter particle concentration in the urine samples. The average correlation values between subsequent US images increased with the particle concentration. The morning urine samples contained an appropriate number of scattering particles to make clinical application of the decorrelation method possible. The fitted correlation curves made an estimation of urine particle concentration possible. The results of this study show that morning urine is suitable for US decorrelation without correcting for differences in particle concentration.

Usefulness of quantifying leukocytes in first-voided urine to predict positivity for Chlamydia trachomatis in asymptomatic men at high risk for chlamydial infection

Chlamydia trachomatis causes acute non-gonococcal urethritis, but some infected men are asymptomatic. We examined leukocytes in uncentrifuged first-voided urine (FVU) from asymptomatic men at high risk for chlamydial infection by automated urine particle analyzers to assess whether the quantification of urinary leukocytes could predict chlamydial infection in these men. We enrolled 209 asymptomatic men, whose female sexual partners had been diagnosed as having a genital chlamydial infection. Their FVU specimens were examined for quantification of leukocytes with automated urine particle analyzers and tested for Neisseria gonorrhoeae, C. trachomatis, Mycoplasma genitalium, Mycoplasma hominis, Ureaplasma parvum, and Ureaplasma urealyticum by nucleotide acid amplification tests. Eleven men positive for N. gonorrhoeae or M. genitalium were excluded from further analysis. In the remaining 198 men, 84 positive for C. trachomatis (42.4%) had 1.8-1666.9 white blood cells (WBCs)/μl (median, 43.3 WBCs/μl) in their FVU, whereas 114 negative for C. trachomatis had 0.1-1378 WBCs/μl (median, 4.8 WBCs/μl). A receiver operating characteristic (ROC) curve was constructed to examine the sensitivity and specificity of leukocytes counts for predicting chlamydial infection. A cut-off point of leukocyte counts of 12.5 WBCs/μl was determined from the ROC curve, resulting in a sensitivity of 86.9% and specificity of 88.6% for predicting chlamydial infection. Leukocyte quantification in FVU by automated urine particle analyzers showed good performance in predicting the positivity and negativity for chlamydial infection in asymptomatic men. This test could potentially develop into a relevant tool for preselecting asymptomatic men prior to C. trachomatis screening.

Development and application of microscopy review criteria of urinalysis combination of dry chemistry and flow cytometry

Objective To establish the review criteria of urinalysis combination of AX-4280 urine dry chemeical analyzer and UF-1000i urine particle analyzer at our laboratory. Methods A total of 4 049 samples were collected randomly from Beijing Hospital of Ministry of Health from December 2010 to December 2011. After analysis on automated analysis line, each sample was examined by two experienced technicians with double-blind method. Their mean results were regarded as the microscopic examination results. The automatic detection and microscopy results of 4 049 samples were analyzed by the UriAccess 3.0 software. The results included BLD LEU and PRO of AX-4280, RBC WBC and CAST of UF-1000i and microscopic examination. The microscopy results were set as the gold standard. And the values of true positive rate, false positive rate, true negative rate, false negative rate and review rate of different combinations of rules were calculated. Then 189 urine samples were examined to validate the feasibility of rules by false negative rate and review rate. Results After analysis, 47 rules were selected for microscopic review. The true positive rate of this review criteria was 32.38% (1 311/4 049), false positive rate 22.33% (904/4 049), true negative rate 43.12% (1 746/4 049), false negative rate 2.17% (88/4 049) and review rate 27.76% (1 124/4 049). The false negative rate of this review criteria was 1.06% (2/189) and review rate 26.46% (50/189). Two cases of missed diagnosis specimens came from renal outpatient department of internal medicine and department of traditional Chinese medicine, the microscopic results of RBC and WBC were 4/HP and 7/HP respectively. So this criteria would not cause a missed diagnosis for patients with severe kidney disease. Conclusions This review criteria can effectively screen the urine samples to diagnose patients with severe kidney disease. So this review criteria is suitable for the screening of urinalysis results at our laboratory. Key words: Urinalysis; Chemistry, analytical; Microscopy; Autoanalysis

Automated recognition of urinary microscopic solid particles

Urine analysis reveals the presence of many problems and diseases in the human body. Manual microscopic urine analysis is time-consuming, subjective to human observation and causes mistakes. Computer aided automatic microscopic analysis can help to overcome these problems. This paper introduces a comprehensive approach for automating procedures for detecting and recognition of microscopic urine particles. Samples of red blood cells (RBC), white blood cells (WBC), calcium oxalate, triple phosphate and other undefined images were used in experiments. Image processing functions and segmentation were applied, shape and textural features were extracted and five classifiers were tested to get the best results. Repeated experiments were done for adjusting factors to produce the best evaluation results. A good performance was achieved compared with many related works.

Evaluation of the Automated Urine Particle Analyzer UF-1000i Screening for Urinary Tract Infection in Nonpregnant Women

Urinary tract infection (UTI) is a widespread disease in women. Urine culture is still the "gold standard" diagnostic test for UTI, but most of them are negative. To reduce unnecessary culture, we evaluated the automated urine particle analyzer UF-1000i screening for UTI in nonpregnant women. The urine specimens submitted to our laboratory were submitted for culture and tested by the Sysmex UF-1000i. Bacteria and white blood cell (WBC) counts were compared to standard urine culture results to assess the best cutoff values. In this study, 272 urine samples were included, of which 98 (36.0%) were culture positive with a bacterial cutoff value of 10 x 10(5) CFU/mL. A combination of bacterial (> 95/microL) and/or WBC count (> 24/microL) provided the best screening for UTI, with a sensitivity of 0.99 and a specificity of 0.82 compared with the urine culture. Sysmex UF-1000i could be used as a screening test for UTI in nonpregnant women. According to the distribution and range of the bacterial scattergram, we could primarily identify and differentiate between Gram-negative and Gram-positive bacteria.

Prevalence of genital mycoplasmas in asymptomatic male partners of women diagnosed as having chlamydial infections

We examined 209 asymptomatic male partners of women diagnosed as having chlamydial infections for the prevalence of Neisseria gonorrhoeae, Chlamydia trachomatis, Mycoplasma genitalium, Mycoplasma hominis, Ureaplasma urealyticum, and Ureaplasma parvum in their first-voided urine (FVU) by nucleic acid amplification tests. Quantification of leukocytes in FVU was performed by automated urine particle analyzers. Two (1.0%) men were positive for N.gonorrhoeae, and 92 (44.0%) were positive for C.trachomatis. In men negative for these pathogens, prevalences of M.genitalium, M.hominis, U.urealyticum, and U.parvum were 0.9%, 29.6%, 27.8%, and 20.1%, respectively, and 58.3% were positive for at least one species of the genital mycoplasmas. Leukocyte counts in FVU from 92 men positive for C.trachomatis were significantly greater than those from 115 men negative for C.trachomatis (p<0.0001). However, there was no significant difference in leukocyte counts between 66 men positive for at least one species of M.hominis, U.urealyticum, and U.parvum and 48 men negative for all the species (p=0.1657). The present population of asymptomatic male partners of women diagnosed as having chlamydial infections showed a low prevalence of M.genitalium infections but would be at high risk of being infected by the other genital mycoplasmas. However, it was still unclear whether these genital mycoplasmas would contribute to the development of inflammation of the male urethra. When these partners are negative for C.trachomatis and N.gonorrhoeae, the recommendation to presumptively treat them to disrupt transmission networks of the genital mycoplasmas would seem premature.

Gender's equality in evaluation of urine particles: Results of a multicenter study of the Italian Urinalysis Group

ObjectiveWe performed a multicenter study to calculate the upper reference limits (URL) for urine particle quantification in mid-stream samples by using automated urine analyzers. Design & methodsTwo laboratories tested 283 subjects using a Sysmex UF-100, two other laboratories tested 313 subjects using Sysmex UF-1000i, whereas two other laboratories tested 267 subjects using Iris IQ®200. ResultsThe URLs of UF-100 in females and males were 7.8/μL and 6.7/μL for epithelial cells (EC), 11.1/μL and 9.9/μL for red blood cells (RBC), 10.2/μL and 9.7/μL for white blood cells (WBC), and 0.85/μL and 0.87/μL for cylinders (CAST). The URLs of UF-1000i in females and males were 7.6/μL and 7.1/μL for EC, 12.2/μL and 11.1/μL for RBC, 11.9/μL and 11.7/μL for WBC, and 0.88/μL and 0.86/μL for CAST. The URLs of Iris IQ®200 in females and males were 7.8/μL and 6.6/μL for EC, 12.4/μL and 10.1/μL for RBC, 10.9/μL and 9.9/μL for WBC, and 1.1/μL and 1.0/μL for CAST. ConclusionThe URLs obtained in this study were comparable to the lowest values previously reported in the literature. Moreover, no gender-related difference was observed, and analyzer-specific upper reference limits were very similar.

Bacterial loads of Ureaplasma urealyticum contribute to development of urethritis in men

Ureaplasma urealyticum could be a pathogen of non-gonococcal urethritis (NGU) in men. However, ureaplasma is often detected in men without NGU, and the proportion of cases possibly attributable to this pathogen is still undefined. We attempted to determine the bacterial loads of U. urealyticum significantly associated with NGU. The 16S rRNA genes of U. urealyticum were quantified by a real-time polymerase chain reaction-based assay in first-void urine (FVU) from 26 asymptomatic and 25 symptomatic men positive for U. urealyticum. The leucocyte counts in first-void urine (FVU) were determined as an objective measure of inflammatory response to ureaplasma in the hosts by automated quantitative urine particle analysis. Positive correlations were observed between copies of the 16S rRNA genes of U. urealyticum per ml and the leucocyte counts per µl in FVU (r = 0.49, p = 0.0003). Loads of ≥10(4) copies of the 16S rRNA gene of U. urealyticum/ml, corresponding to ≥5 × 10(3) cells of U. urealyticum/ml in FVU, were significantly associated with the presence of urethritis symptoms (p < 0.0001) and with higher leukocyte counts in FVU (p < 0.0001). The bacterial load of U. urealyticum, possibly of ≥5 × 10(3) cells of U. urealyticum/ml in FVU, could be significantly associated with the development of symptomatic NGU.

Pediatric reference values for urine particle quantification by using automated flow cytometer: Results of a multicenter study of Italian urinalysis group

ObjectivesThe purpose of this Italian multicenter study was to define pediatric upper reference values for urine particle quantification by using automated flow cytometry. Design and methodsFour hospital-based clinical laboratories participated in this multicenter investigation, which included a total study population of 161 Italian children aged from 1 to 12years. Two laboratories used Sysmex UF-100 and analyzed 86 children, whereas the other two used Sysmex UF-1000i and analyzed 75 subjects. Particle quantification included the analysis of white blood cells (WBC), red blood cells (RBC), squamous epithelial cells (EC), transitional epithelial cells (TC), casts (CAST) and bacteria (BACT). ResultsThe upper reference values in subjects tested with the Sysmex UF-100 were 9.7WBC/μL, 10.1RBC/μL, 7.5EC/μL, 2.5TC/μL, 0.7CAST/μL and 3090BACT/μL, whereas the upper reference values in subjects tested with the Sysmex UF-1000i were 10.5WBC/μL, 8.3RBC/μL, 7.2EC/μL, 2.9TC/μL, 0.7CAST/μL and 48BACT/μL. No statistically significant differences between genders were found in the value distribution of any of the parameters tested. Similarly, no statistically significant differences were observed between the two urine analyzers, except for BACT. ConclusionsAutomated analysis of urine particles appears a suitable means to optimize the workflow of routine urinalysis of children specimens. The upper reference limits for pediatric subjects obtained in this study were comparable to those previously reported in the literature, with no significant differences between genders and analyzers.

Clinical Laboratory Urine Analysis: Comparison of the UriSed Automated Microscopic Analyzer and the Manual Microscopy

Several automated urine sediment analyzers have been introduced to clinical laboratories. Automated microscopic pattern recognition is a new technique for urine particle analysis. We evaluated the analytical and diagnostic performance of the UriSed automated microscopic analyzer and compared with manual microscopy for urine sediment analysis. Precision, linearity, carry-over, and method comparison were carried out. A total of 600 urine samples sent for urinalysis were assessed using the UriSed automated microscopic analyzer and manual microscopy. Within-run and between-run precision of the UriSed for red blood cells (RBC) and white blood cells (WBC) were acceptable at all levels (CV < 20%). Within-run and between-run imprecision of the UriSed testing for cast, squamous epithelial cells (EPI), and bacteria (BAC) were good at middle level and high level (CV < 20%). The linearity analysis revealed substantial agreement between the measured value and the theoretical value of the UriSed for RBC, WBC, cast, EPI, and BAC (r > 0.95). There was no carry-over. RBC, WBC, and squamous epithelial cells with sensitivities and specificities were more than 80% in this study. There is substantial agreement between the UriSed automated microscopic analyzer and the manual microscopy methods. The UriSed provides for a rapid turnaround time.

Development of Microscopic Review Criteria by Comparison Urine Flow Cytometer, Strip and Manual Microscopic Examination

Microscopic examination is essential for urine analysis, but a time-consuming procedure. This study was undertaken to evaluate an automated urinalysis system - the Sysmex UF-1000i (URISYS 2400) for the analysis of urine constituents including chemistry components and particles. The objective was to screen urine samples and determine the screening criteria which would minimize the number of specimens reviewed with the microscope yet ensuring correct results. A total of 1300 urine samples were sent for urinalysis using the automated system and compared with results obtained from manual microscopy using the Fuchs-Rosenthal counting chamber. Using Pearson statistics, we observed correlation between the UF-1000i and manual microscopy: for red blood cells (RBCs) r was 0.949, for white blood cells (WBCs) r was 0.882, for epithelial cells (EC) r was less than 0.76, for casts r was less than 0.7, while correlation between the URISYS 2400 and manual microscopy: for red blood cells r was 0.772 and for white blood cells r was 0.771. With the help of Uriaccess (an expert system provided by the Sysmex Corporation), 37 rules for microscopic review were set up. The review rules were validated, the review rate was less than 30% and the false-positive and false-negative results were acceptably low. UF-1000i is capable of reproducible measurement of urine particles within the clinically relevant range and shows its advantage over URISYS 2400. It is an optimal strategy for urine sample screening using the combination of the two methods.

Rapid Discrimination of Gram-Positive and Gram-Negative Bacteria in Liquid Samples by Using NaOH-Sodium Dodecyl Sulfate Solution and Flow Cytometry

BackgroundFor precise diagnosis of urinary tract infections (UTI), and selection of the appropriate prescriptions for their treatment, we explored a simple and rapid method of discriminating gram-positive and gram-negative bacteria in liquid samples.Methodology/Principal FindingsWe employed the NaOH-sodium dodecyl sulfate (SDS) solution conventionally used for plasmid extraction from Escherichia coli and the automated urine particle analyzer UF-1000i (Sysmex Corporation) for our novel method. The NaOH-SDS solution was used to determine differences in the cell wall structures between gram-positive and gram-negative bacteria, since the tolerance to such chemicals reflects the thickness and structural differences of bacterial cell walls. The UF-1000i instrument was used as a quantitative bacterial counter. We found that gram-negative bacteria, including E. coli, in liquid culture could easily be lysed by direct addition of equal volumes of NaOH-SDS solution. In contrast, Enterococcus faecalis, which is a gram-positive bacterium, could not be completely lysed by the solution. We then optimized the reaction time of the NaOH-SDS treatment at room temperature by using 3 gram-positive and 4 gram-negative bacterial strains and determined that the optimum reaction time was 5 min. Finally, in order to evaluate the generalizability of this method, we treated 8 gram-positive strains and 8 gram-negative strains, or 4 gram-positive and 4 gram-negative strains incubated in voluntary urine from healthy volunteers in the same way and demonstrated that all the gram-positive bacteria were discriminated quantitatively from gram negative bacteria using this method.Conclusions/SignificanceUsing our new method, we could easily discriminate gram-positive and gram-negative bacteria in liquid culture media within 10 min. This simple and rapid method may be useful for determining the treatment course of patients with UTIs, especially for those without a prior history of UTIs. The method may be easily applied in order to obtain additional information for clinical prescriptions from bacteriuria.

A flow cytometric urine analyzer for bacteria and white blood cell counts plus urine dipstick test for rapid screening of bacterial urinary tract infection

Background: Bacterial urinary tract infection (UTI) is one of the most common patient problems that have no reliably definite diagnosis. The gold standard urine culture is usually delayed and increases laboratory workload. Objectives: To find a rapid method for the screening of bacterial urinary tract infection, the performance of four urinalysis parameters from automated urine dipstick test and flow cytometry were evaluated against the urine culture method. Methods: Urine cultures were performed on 372 routine specimens of suspected UTI. Urine dipstick tests were performed using an automated reader. An automated urine particle analyzer was used for quantitative counting of bacteria and white blood cells. Results: For screening of UTI, urinary bacteria count >14.2 cells/?L gave the highest sensitivity of 95.76% and 44.88% specificity. Conclusion: We suggest using urinary bacteria count for screening of UTI. This method can reduce the laboratory workload for processing urine culture by 30.64%. Keywords: Flow cytometry, urinalysis, urine dipstick, UTI

UrineCART, a machine learning method for establishment of review rules based on UF-1000i flow cytometry and dipstick or reflectance photometer

Automated systems have been broadly used in the counting of particles in urine, while manual microscopic analyses are still required for confirming components of urine sediments, especially pathologic casts and other unknown particles. Good review rules can reduce the number of manual urine microscopy examinations safely, thereby increasing productivity. Although several methods have been proposed,establishment of microscopic review rules for fl ow cytometer remains challenging. A total of 3014 urine samples from outpatient and inpatient were examined using UF-1000i flow cytometry,Urisys-2400 dipstick and RS 2003 urine sediment workstation,respectively. Based on the results above, three supervised machine learning methods were employed to construct classifiers for screening urine samples. Here, we propose a novel method for construction of microscopic review rules, termed UrineCART, which was based on a classification and regression tree (CART) method.With a cut-off value of 0.0745 for Urine CART, we obtained a sensitivity of 92.0 % , a specificity of 81.5 % and a total review rate of 32.4 % on an independent test set. Comparisons with the existing methods showed that Urine CART gave the acceptable sensitivity and lower total review rate. An algorithm based on machine learning methods for review criteria can be achieved via systematic comparison of UF-1000i flow cytometry and microscopy.Using Urine CART, our microscopic review rate can be reduced to around 30 % , while decreasing significant losses in urinalysis.

The standardization of urine particle counting in medical laboratories – a Polish experience with the EQA programme

Background: Given the common problems with the standardization of urine particle counting methods and the great variability in the results obtained by Polish laboratories under international Labquality External Quality Assessment (EQA), we initiated educational recovery activities. Methods: Detailed instructions on how to perform the standardized examination were sent to EQA participants, as was a questionnaire forms which enabled information to be gathered in respect to the procedures being applied. Laboratory results were grouped according to the method declared on the EQA ‘Result’ form or according to a manual examination procedure established on the basis of the questionnaire. The between-laboratory CVs for leukocyte and erythrocyte counts were calculated for each group and compared using the Mann-Whitney test. Results: Significantly lower between-laboratory CVs (p = 0.03) were achieved for leukocyte counting among the laboratories that analysed control specimens in accordance with standardized procedures as compared with those which used non-standardized procedures. We also observed a visible lower variability for erythrocyte counting. Unfortunately despite our activities, only a few of the Polish laboratories applied the standardized examination procedures, and only 29% of the results could have been considered to be standardized (16% – manual methods, 13% – automated systems). Conclusions: The standardization of urine particle counting methods continues to be a significant problem in medical laboratories and requires further recovery activities which can be conducted using the EQA scheme.

Biochemical Composition of Normal Urine

AbstractThe urine composition defines the quality of homeostasis of the body. Learning about the normal urine composition is very important to compare it with the suspended and non suspended particles in urine in different pathologies.

Fluorescence flow cytometer to determine urine particle reference intervals in doping control samples

Urine is still the matrix of choice to fight against doping, because it can be collected non-invasively during anti-doping tests. Most of the World Anti-Doping Agency's accredited laboratories have more than 20 years experience in analyzing this biological fluid and the majority of the compounds listed in the 2010 Prohibited List-International Standard are eliminated through the urinary apparatus. Storing and transporting urine samples for doping analyses does not include a specific protocol to prevent microbial and thermal degradation. The use of a rapid and reliable screening method could enable determine reference intervals for urine specimens in doping control samples and evaluate notably the prevalence of microbial contamination known to be responsible for the degradation of chemical substances in urine. The Sysmex® UF-500i is a recent urine flow cytometer analyzer capable of quantifying BACT and other urinary particles such as RBC, WBC, EC, DEBRIS, CAST, PATH.CAST, YLC, SRC as well as measuring urine conductivity. To determine urine anti-doping reference intervals, 501 samples received in our laboratory over a period of two months were submitted to an immediate examination. All samples were collected and then transported at room temperature. Analysis of variance was performed to test the effects of factors such as gender, test type [in-competition, out-of-competition] and delivery time. The data obtained showed that most of the urine samples were highly contaminated with bacteria. The other urine particles were also very different according to the factors. The Sysmex® UF-500i was capable of providing a snapshot of urine particles present in the samples at the time of the delivery to the laboratory. These particles, BACT in particular, gave a good idea of the possible microbial degradation which had and/or could have occurred in the sample. This information could be used as the first quality control set up in WADA (World Anti-Doping Agency) accredited laboratories to determine if steroid profiles, endogenous and prohibited substances have possibly been altered.

Prospective monitoring of BK virus reactivation in renal transplant recipients in North India

BK nephropathy (BKN) is an important complication of renal transplantation with a reported incidence between 1% and 10% in different parts of the world. Early diagnosis is important to plan early therapeutic strategies. The epidemiology and evolution of BKN is relatively unknown in India and hence, the present study has been designed to prospectively monitor the activation of BK virus (BKV) in renal transplant recipients in India. In this study, 32 renal allograft recipients were prospectively monitored with protocol biopsies of allografts, BKV DNA load in plasma, and viral particles in urine by electron microscopy (EM) on day 1, and at 1, 3, and 6 months. Additionally, the baseline BKV DNA load in plasma was quantitated in 21 corresponding donors. On follow-up in 32 recipients, 9.7%, 23.8%, 19.2%, and 13.3% of patients showed viral profiles by EM at day 1, 1 month, 3 months, and 6 months, respectively. BKV DNA positivity in plasma was 25.8%, 42.9%, 15.4%, and 20% at day 1, 1 month, 3 months, and 6 months, respectively, with mean BKV copy number/mL plasma of 1796, 1029, 2611, and 3318, respectively. A total of 15.7% (17/108) urine samples of 32 renal recipients were positive by urine EM. Out of 100 protocol biopsies, none developed histologically demonstrable cytopathic effects of BKN, although 8% biopsies were SV-40 large T antigen (SV-40 T Ag) positive. By quantitative real-time polymerase chain reaction assay, 27/108 (25%) of recipients' plasma samples were positive for BKV. Peak viremia and viruria occurred at 1-3 months post transplantation. The baseline viremia in donors was predictive of viremia positivity in the post-transplantation period at 1 month. Twenty-four episodes of graft dysfunction were attributed mainly to rejection. The study shows a total of 15.7% and 25% urine and plasma samples were positive for BKV at any time during a 6-month follow-up. The highest incidence of BK viruria and viremia occurred at 1 month. In protocol biopsies, focal positivity of SV-40 T Ag was seen in 8% biopsies.

Urine particles analysis: Performance evaluation of Sysmex UF-1000i and comparison among urine flow cytometer, dipstick, and visual microscopic examination

Introduction. Our objective was to evaluate a newly invented urine flow cytometer, and select an optimal strategy for urinalysis in clinical practice. Methods. The performance of UF-1000i was evaluated in both control material and patient samples. A total of 1631 specimens were collected and analysed by visual microscopy examination (VME), UF-1000i flow cytometer (Sysmex Medical Electronics Co, Kobe, Japan) and an automated dipstick reflectometer Clinitek Atlas (Bayer Corp, Elkhart, USA). Results. UF-1000i showed good imprecision performance for the main parameters in urine particles with CV values less than 20%. The results from UF-1000i correlated well with VME for erythrocytes (r = 0.96), leukocytes (r = 0.98), and epithelial cell (r = 0.84). The area under the receiver operating curve (AUC) was 0.879, 0.903, 0.783, and 0.817 respectively for erythrocytes, leukocytes, bacteria and CAST in UF-1000i. While in Clinitek Atlas, the AUC was 0.848, 0.803, 0.761, and 0.754 respectively. Sensitivity of combination of the two methods for screening remained at 98% as compared to VME alone, while reducing the visual review rate down to 40%. Conclusion. UF-1000i is capable of reproducible measurement of urine particles in the clinically relevant range and shows its advantage over Atlas. Combination of the two methods is an optimal strategy for urine sample screening.

A Theoretical and Practical Course on Urine Microscopy in Nigeria: A Model for Nephrological Skill Transfer

Background: In the developing world, the diagnostic power of nephrologists is heavily limited by financial, technical and human resource constraints. Urine microscopy (UM) is a basic, inexpensive and relatively simple diagnostic tool, which supplies irreplaceable information. Recently, a theoretical and practical course on UM was organized during the 22nd annual meeting of the Nigerian Society of Nephrology. Methods: The 2-day course was based on power point presentations and on examination of true urine samples by means of a microscope equipped with phase contrast, polarized light and a video camera for projection of the findings. Results: The presentations described were the methodology, the particles of the urine sediment and their clinical interpretation, the urine sediment in different clinical conditions, and 12 clinical cases, which demonstrated the value of UM in clinical practice. Practical sessions showed the most important urine particles, and how they could be identified and combined into urine profiles. More than 97% of the participants found the course to be useful and practicable and a UM program was actually started in 1 Nigerian center a few days after the course. Conclusion: This course demonstrated that nephrological skills can be transferred from the developed to the developing world without large financial investments.