The EFLM European Urinalysis Guideline 2023.

BACKGROUND: The EFLM Task and Finish Group Urinalysis has updated the ECLM European Urinalysis Guidelines (2000) on urinalysis and urine bacterial culture, to improve accuracy of these examinations in European clinical laboratories, and to support diagnostic industry to develop new technologies. RECOMMENDATIONS: Graded recommendations were built in the following areas. MEDICAL NEEDS AND TEST REQUISITION: Strategies of urine testing are described to patients with complicated or uncomplicated urinary tract infection (UTI), and high or low-risk to kidney disease. SPECIMEN COLLECTION: Patient preparation, and urine collection are supported with two quality indicators: contamination rate (cultures), and density of urine (chemistry, particles). CHEMISTRY: Measurements of both urine albumin and α1-microglobulin are recommended for sensitive detection of kidney disease in high-risk patients. Performance specifications are given for urine protein measurements and quality control of multiproperty strip tests. PARTICLES: Procedures for microscopy are reviewed for diagnostic urine particles, including urine bacteria. Technologies in automated particle counting and visual microscopy are updated with advice how to verify new instruments with the reference microscopy. BACTERIOLOGY: Chromogenic agar is recommended as primary medium in urine cultures. Limits of significant growth are reviewed, with an optimised workflow for routine specimens, using leukocyturia to reduce less important antimicrobial susceptibility testing. Automation in bacteriology is encouraged to shorten turn-around times. Matrix assisted laser desorption ionization time-of-flight mass spectrometry is applicable for rapid identification of uropathogens. Aerococcus urinae, A. sanguinicola and Actinotignum schaalii are taken into the list of uropathogens. A reference examination procedure was developed for urine bacterial cultures.

Improving Management: Novel Guidelines for Diagnosing Urinary Tract Infection in Infants.

BACKGROUND: The diagnosis of urinary tract infection (UTI) in the pediatric field remains a topic of debate. In 2011, the American Academy of Pediatrics (AAP) introduced new guidelines for the diagnosis of UTI in patients 2-24 months old. However, concerns were raised regarding these guidelines. METHODS: This is a retrospective data extraction study that included patients 0-6 months of age who were examined in the pediatric emergency department between 2016 and 2021 and had a urine culture. For each patient, we recorded the diagnosis documented in the medical records, the diagnosis based on the AAP and Israeli guidelines, and the diagnosis according to our 2 proposed protocols. We then compared the percentage of UTI diagnoses according to each diagnostic guideline. RESULTS: A total of 1432 patients under the age of 6 months underwent urine culture testing during the study period. A total of 83 (5.81%) of these patients were diagnosed with UTI according to the AAP guidelines, 184 of the patients (12.8%) were diagnosed with UTI according to the Israeli guidelines, 102 (7.1%) and 109 (7.6%) of the patients were diagnosed with UTI according to our first and second proposed guidelines, respectively. CONCLUSIONS: We propose a new diagnostic method (guidelines II) that is suitable for patients older than 2 months, with obligatory criteria of abnormal urine test and a lower threshold for the colony count required for diagnosis compared to the AAP guidelines. Further research is required to examine the sensitivity and specificity of our proposed guidelines, so it may replace the current diverse guidelines.

Can sodium and potassium measured in timed voids be used as reference instruments for validating self-report instruments? Results from a urine calibration study.

BACKGROUND: Sodium and potassium measured in 24-h urine collections are often used as reference measurements to validate self-reported dietary intake instruments. OBJECTIVES: To evaluate whether collection and analysis of a limited number of urine voids at specified times during the day ("timed voids") can provide alternative reference measurements, and to identify their optimal number and timing. METHODS: We used data from a urine calibration study among 441 adults aged 18-39 y. Participants collected each urine void in a separate container for 24 h and recorded the collection time. For the same day, they reported dietary intake using a 24-h recall. Urinary sodium and potassium were analyzed in a 24-h composite sample and in 4 timed voids (morning, afternoon, evening, and overnight). Linear regression models were used to develop equations predicting log-transformed 24-h urinary sodium or potassium levels using each of the 4 single timed voids, 6 pairs, and 4 triples. The equations also included age, sex, race, BMI (kg/m2), and log creatinine. Optimal combinations minimizing the mean squared prediction error were selected, and the observed and predicted 24-h levels were then used as reference measures to estimate the group bias and attenuation factors of the 24-h dietary recall. These estimates were compared. RESULTS: Optimal combinations found were as follows: single voids-evening; paired voids-afternoon + overnight (sodium) and morning + evening (potassium); and triple voids-morning + evening + overnight (sodium) and morning + afternoon + evening (potassium). Predicted 24-h urinary levels estimated 24-h recall group biases and attenuation factors without apparent bias, but with less precision than observed 24-h urinary levels. To recover lost precision, it was estimated that sample sizes need to be increased by ∼2.6-2.7 times for a single void, 1.7-2.1 times for paired voids, and 1.5-1.6 times for triple voids. CONCLUSIONS: Our results provide the basis for further development of new reference biomarkers based on timed voids. CLINICAL TRIAL REGISTRY: clinicaltrials.gov as NCT01631240.

[Evaluation of an algorithm based on quantitative assays of glomerular parameters (albuminuria and urinary IgG) for proteinuria typing]. / Évaluation d'un algorithme basé sur des dosages quantitatifs de paramètres glomérulaires (albuminurie et IgG urinaires) afin de typer une protéinurie.

The first orientation test for proteinuria typing is electrophoresis. However, this technique has several drawbacks, such as delayed turnaround time and subjective readings. Some laboratories therefore use quantitative assays of glomerular markers combined with tubular markers. However, the cost of reagents and the instability of certain markers are significant drawbacks for some peripheral laboratories. The aim of this study is to evaluate the implementation of an algorithm based on parameters that can be used by all laboratories for proteinuria typing within a timeframe compatible with the urgency of the situation. Albuminuria and urinary IgG were determined on 161 urines. ROC curves were produced, using urine electrophoresis read by an expert center as the reference method. The decision thresholds used are: glomerular proteinuria is defined by a Albumin+IgGproteinsratio greater than 75.4% (100% specificity), and tubular or overload proteinuria is defined by by a Albuminproteinsratio less than 37.3% (100% sensitivity). Agreement between the results of the algorithm selected and the reference method used in our study was 88 %, with a kappa value of 0.807 (95% CI [0.729 to 0.885]). The algorithm's performance suggests that it can find its place in the diagnostic strategy for clinically significant proteinuria, despite its limited indications. It is up to each biologist to assess the value of this algorithm in relation to the recruitment, habits and needs of clinicians.

Padronização da avaliação da função renal de ratos (Rattus norvegicus) Wistar do biotério da Universidade Federal de Juiz de Fora / Standardization of renal function evaluation in Wistar rats (Rattus norvegicus) from the Federal University of Juiz de Fora's colony

Introdução: Há grande interesse na utilização de modelos animais na pesquisa da fisiopatologia renal, que requer padronização dos parâmetros analisados. Objetivo: Padronizar avaliação da função renal de ratos da colônia do biotério do Centro de Biologia da Reprodução da Universidade Federal de Juiz de Fora. Métodos: Foram utilizados 30 ratos Wistar e realizadas dosagens de creatinina (sérica e urinária), ureia sérica e proteinúria. Foram avaliados: o intervalo de coleta de urina nas gaiolas metabólicas (24 horas ou 12 horas); a necessidade de jejum de 12 horas; a necessidade de desproteinização das amostras de urina e soro para dosagens de creatinina; necessidade de desproteinização do soro de animais com injúria renal aguda (IRA) para leitura em espectrofotômetro e ELISA, além da comparação da proteinúria de 24 horas (PT 24 horas) com a relação proteína/creatinina (rP/C). Os resultados foram comparados pelos teste t de Student, correlação de Pearson, gráfico de Bland-Altman para concordância e modelo de regressão linear para estimar a PT 24 horas a partir da rP/C. Resultados: A diurese de 24 horas foi maior do que a de 12 horas, interferindo na depuração da creatinina. No grupo em jejum, houve menor ingestão hídrica e menor creatinina urinária. Houve grande variabilidade para o soro desproteinizado e as leituras realizadas nos dois equipamentos foram semelhantes. Houve forte correlação entre PT 24 horas e rP/C e foi gerada a equação: PT 24 horas = (8,6113 x rP/C) + 1,0869. Conclusão: Foi padronizada: coleta de urina em 24 horas sem jejum. A desproteinização não mostrou benefício. As dosagens foram realizadas com confiabilidade em espectrofotômetro. Foi ...

Introduction: There is great interest in the use of animal models in the study of renal pathophysiology requires standardization of parameters. Objective: Standardize assessment of renal function in rats from in the Center for Reproductive Biology of Federal University of Juiz de Fora's colony. Methods: Thirty Wistar rats were used and performed measurements of creatinine (serum and urine), serum urea and proteinuria. Were evaluated: the urine collection interval in metabolic cages (24 hours or 12 hours), the need for 12-hour fast, the need of urine and serum deproteinization for creatinine measurement, need of serum deproteinization in animals with acute kidney injury to a spectrophotometer and ELISA, and the comparison of 24-hour proteinuria (PT 24 hours) with the protein/creatinine ratio (rP/C). Means were compared by the Student's t test, Pearson correlation, Bland-Altman plot for agreement and linear regression model to estimate PT 24 hours from rP/C. Results: The 24 hours urine output was greater than 12 hours, interfering with the creatinine clearance calculation. In the fasting group showed less water intake and lower urinary creatinine. There was great variability for the deproteinized whey and readings performed in the two devices were similar. There was a strong correlation between PT 24 hours and rP/C and the equation was generated: PT 24 hours = (8.6113 x rP/C) + 1.0869. Conclusion: Was standardized: 24-hour urine collection without fasting. The deproteinization showed no benefit. The measurements were performed with spectrophotometer reliability. It generated a practical formula for estimating PT 24 hours through rP/C. .

Evaluación de un sistema automatizado de siembra de orinas para urocultivos / Evaluation of an automated streaking system of urine samples for urine cultures

Introduction: Automated systems have simplified laboratory workflow, improved standardization, traceability and diminished human errors and workload. Although microbiology laboratories have little automation, in recent years new tools for automating pre analytical steps have appeared. Objectives: To assess the performance of an automated streaking machine for urine cultures and its agreement with the conventional manual plating method for semi quantitative colony counts. Materials and Methods: 495 urine samples for urinary culture were inoculated in CPS® agar using our standard protocol and the PREVI™ Isola. Rates of positivity, negativity, polymicrobial growth, bacterial species, colony counts and re-isolation requirements were compared. Results: Agreement was achieved in 98.97% of the positive/negative results, in 99.39% of the polymicrobial growth, 99.76% of bacterial species isolated and in 98.56 % of colony counts. The need for re-isolation of colonies decreased from 12.1% to 1.1% using the automated system. Discussion: PREVI™ Isola's performance was as expected, time saving and improving bacterial isolation. It represents a helpful tool for laboratory automation.

Introducción: Los sistemas automatizados han facilitado el flujo de trabajo, mejorado la estandarización, la trazabilidad, disminuido el error humano y la carga de trabajo en los laboratorios. A pesar de que la microbiología ha permanecido poco automatizada, en los últimos años han aparecido nuevas herramientas para la automatización de la etapa pre analítica. Objetivos: Evaluar el desempeño de un sistema automatizado de siembra de urocultivos y la concordancia con la siembra manual convencional en el recuento semicuantitativo de colonias. Materiales y Métodos: 495 muestras de orinas fueron sembradas según nuestro protocolo habitual y comparadas con las placas de CPS® obtenidas con PREVI™ Isola en cuanto a positividad/negatividad, muestras polimicrobianas, especies de bacterias aisladas, recuentos y necesidad de resembrar. Resultados: Hubo concordancia en 98,97% de los positivos y negativos, en 99,39% de las muestras polimicrobianas, en 99,76% de las especies aisladas y en 98,56% de los recuentos. La necesidad de resiembra disminuyo de 12,1% a un 1,1% usando este sistema automatizado. Discusión: El desempeño de PREVI™ Isola fue el esperado, mejorando el aislamiento bacteriano y el tiempo requerido y representa una buena herramienta para la automatización de laboratorios.

El segundo bienio del Programa de Evaluación Externa de Calidad en Uroanálisis (PEECU) / The second biennial of the External Quality Evaluation Program in Urinalysis (PEECU)

OBJECTIVE: To characterize the participation of clinical laboratories in the second biennial of an external quality assurance scheme for urinalysis in Mexico. METHODS: The participants received 32 control samples in 8 shipments of 4 controls each during the biennial 1999-2000. The controls were in the form of tablets to be dissolved in 12 mL of water to mimic urine. The participants performed dipstick assays of pH, specific gravity (SG) and 8 analytes (proteins, glucose, ketones, blood, bilirubin, nitrites, urobilinogen, leukocytes) in the controls. Expected control values were assigned by 10-15 replicate automated assays using dipsticks and apparatus of a single provider (Bayer). Participants' results were transformed to scores ranging from zero (perfect result) to 400 (worst possible). Score differences were analyzed using nonparametric methods (Kruskal-Wallis and Mann-Whitney). RESULTS: The best results were seen for nitrites, ketones and proteins (mean global scores = 3-5) and the worst for SG (score = 45) with intermediate scores of 10-13 for the other six. CONCLUSIONS: The scores improved for the second biennial from a grand mean of 17 in the first significantly down to 12 in the second. The number of participants has been increasing yearly and there has been a decrease of participants who do not report at least 3 out of 4 yearly shipments. We confirmed that automated readings yield better scores than visual readings.

Proposta de um modelo de padronizaçäo para o exame sumário de urina / Proposal to standardization model for the urinalysis

O exame sumário de urina representa sem dúvida um elemento indispensável na detecçäo de diversas doenças do trato urinário, metabólicas ou sistêmicas näo relacionadas com o rim. Quando realizado e interpretado criteriosamente, oferece ao solicitante valiosas informaçöes para o esclarecimento diagnóstico. O presente trabalho tem como objetivo propor um modelo de padronizaçäo de resultados, descritos de acordo com o exame físico (volume, cor, aspecto, depósito e densidade), pesquisas bioquímicas realizadas através de tiras reativas (pH, proteínas, glicose, corpos cetônicos, hemoglobina, urobilinogênio, bilirrubina, esterase leucocitária e nitrito) e os elementos encontrados na sedimentoscopia urinária (células epiteliais de descamaçäo, leucócitos, hemácias, cilindros, bactérias, muco, cristais, sais amorfos, leveduras, espermatozóides e parasitas). Além desses parâmetros, algumas observaçöes podem ser descritas, quando necessárias, com a finalidade de fornecer informaçöes ao clínico que possam auxiliar no diagnóstico de doenças mais específicas. Sabe-se da existência de vários interferentes na urina que podem provocar reaçöes falso-negativas. Por este motivo, a confirmaçäo de alguns componentes urinários (proteínas, glicose, bilirrubina e urobilinogênio) é necessária para garantir a exatidäo do resultado. A padronizaçäo de procedimentos poderá evitar as diferentes formas de transcriçäo do laudo interlaboratorial, o que ocasiona interpretaçäo e tratamento inadequados

Los dos primeros años del programa de evaluación externa de calidad en uroanálisis (PEECU) / The firts two years of an external quality assurance scheme for strip uroanalysis

Objetivo. Analizar los datos de uroanálisis con tira reactiva generados en los primeros dos años de un programa externo de control de calidad. Métodos. Los participantes recibieron 32 controles (4 por 8 envíos) en forma de tabletas para disolver y analizar usando tiras reactivas de uroanálisis. El número de participantes aumentó de < 50 en el 1er. envío a > 200 en el 8o. Midieron de 6 a 10 analitos según el tipo de tira utilizada y enviaron 763 informes. En cada informe se calculó una puntuación por analito (n = 4), por envío (n = 24 a 40) y una global de los 8 envíos (n = 707 a 763), La puntuación de obtuvo comparando el resultado informado con la moda de unos 600 laboratorios de Canadá y EEUU que midieron los mismos 32 controles utilizando exclusivamente tiras Bayer y lecturas instrumentales. La puntuación se extendió de cero ideal a un máximo de 400 puntos malos. Resultados. la mejor puntuación global (3 puntos en 741 informes) fue en nitritos y la peor (58 puntos en 744 informes) en gravedad específica (GE). Los otros ocho analitos tuvieron globales de 11 a 19 puntos (tabla 1). Las puntuaciones más bajas por tipo de métodos (tabla 2) fueron con tiras y aparatos automatizados Bayer (global de 13 puntos) y las lecturas visuales con tiras Bayer (global de 21). Conclusiones. 1. Los resultados nos llevaron a la decisión de suspender el envío de controles a participantes que usan tiras de otras marcas ya que el programa, por estar diseñado por usuarios de tiras Bayer, puede contribuir desorientar a los usuarios de otras tiras. 2. Se confirmó que la lectura instrumental es superior a la visual. 3. Ameritan estudio las causas de la puntuación alta de GE