Desempenho de diferentes marcas de tiras reagentes relativo à densidade e à análise química da urina de cães e gatos / Performance of different brands of reagent strips for density and chemical analysis of dog and cat urine

Objetivou-se verificar a compatibilidade entre diferentes marcas de tiras reagentes para urinálise, tanto de uso veterinário, como de uso humano, e confrontar os parâmetros semiquantitativos desse instrumento com métodos quantitativos. Para isso, foram analisadas 77 amostras frescas de urina de cães e gatos e testados 04 modelos de tiras reagentes. Quanto à densidade urinária, houve correlação razoável entre os métodos quantitativo e semiquantitativo naquelas amostras com pH ácido, mas não naquelas com pH neutro ou alcalino. Quanto à concentração proteica, houve similaridade de 53,3% a 83,3% entre as marcas testadas e quando comparadas com a análise fotométrica houve uma correlação razoável (rs = 0,69752 a 0,75074). Em ponto de corte de 15mg/dL de proteína, a sensibilidade da tira reagente foi 82,5% e 100% para urina canina e felina, respectivamente. No tocante à hematúria, houve divergência razoável entre a sedimentoscopia e as diferentes marcas de tiras reativas. Quanto à piúria, há uma baixa sensibilidade das tiras em relação às amostras caninas com muitos resultados falso-negativos (33% a 75%), enquanto em amostras felinas a sensibilidade foi de 100%. Assim, independente da marca, as tiras reagentes devem servir apenas como teste rápido de triagem, sendo mais apropriado o uso de métodos quantitativos na avaliação clínica do paciente a partir da urinálise.

The aim was to verify the compatibility between different brands of urinary dipsticks, for both human and veterinary use, and to compare the semiquantitative parameters of this instrument with quantitative methods. For this, 77 fresh samples of urine from dogs and cats were analyzed e and 04 models of reagent strips were tested. Regarding urinary density, a reasonable correlation was observed between the quantitative and semiquantitative methods in those samples with acidic pH, which did not occur in those with neutral or alkaline pH. Regarding the protein concentration, there was similarity from 53.3% to 83.3% between the brands and in the comparative analysis between the control strip and the photometric analysis, there was a reasonable correlation (rs = 0.69752 to 0.75074). In cut-off point of 15mg/dL protein, the sensitivity of the reagent strip was 82.5% and 100% for canine and feline urine, respectively. Regarding hematuria, there was a reasonable divergence of results between sedimentation and tested dipsticks. As for pyuria, there is a low sensitivity of the strips in relation to canine samples with many false negative results (33% to 75%), while in feline samples the sensitivity was 100%. Thus, regardless of the brands, the reagent strips should serve only as a rapid screening test, while the use of quantitative methods in the clinical evaluation of the patient from urinalysis is more appropriate.

Preparation of an anti-cotinine monoclonal antibody and its application in immunological detection / 浙江大学学报·医学版

OBJECTIVE@#To prepare monoclonal antibody against cotinine (COT) and to establish immunoassay for detecting COT in human urinary samples.@*METHODS@#BALB/c mice were immunized with synthesized cotinine-bovine serum albumin (COT-BSA) to screen monoclonal antibody with technique of cell fusion. The monoclonal antibody was used for the indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) and colloidal gold immunochromatographic strip assay for the detection of COT in human urine.@*RESULTS@#The monoclonal antibody against COT was identified by ic-ELISA with a 50%inhibitive concentration (IC@*CONCLUSIONS@#The ic-ELISA and colloidal gold immunochromatographic strip assay using the prepared monoclonal antibody against COT have been proved to be reliable for the rapid detection of COT in human urines, which may be used for monitoring of environmental tobacco smoke.

Avaliação microscópica do sedimento urinário no exame deurina de rotina: comparação entre dois métodos / Microscopic evaluation of urinary sediment on routine urinalysis: comparison between two methods

Objetivo: O objetivo foi avaliar a concordância entre o método de sedimentoscopia proposto pela Associação Brasileira de Normas Técnicas e o método proposto pela Sociedade Brasileira de Patologia Clínica/Medicina Laboratorial. Métodos: A partir da urina de nove indivíduos, foram obtidas 72 amostras analisadas por ambos os métodos. Cada amostra foi examinada por quatro avaliadores. A concordância entre os métodos foi medida através do coeficiente de correlação de Pearson (r) para as variáveis contínuas e o coeficiente de concordância kappa (k) para as categóricas. Resultados: Houve concordância entre os métodos para a quantificação de cilindros leucocitários (97,2%, k = 0,61, p<0,01), e presença de cristais de oxalato de cálcio (77,8%, k = 0,43, p=0,04), cilindros hialinos (88,9%, k = 0,51, p=0,04), sais de uratos amorfos (83,3%, k = 0,59, p=0,03), fios mucosos (83,3%, k = 0,48, p=0,04) e leveduras (75,9%, k = 0,54, p=0,04). Os métodos tiveram correlação moderada quanto ao número de hemácias (r = 0,56, p=0,04) e células epiteliais (r = 0,73, p=0,04). Destaca-se um maior tempo de processamento e leitura da amostra para o método proposto pela SBPC/ML (23,4 min) quando comparado com o da ABNT NBR 15268 (16,6 min, p<0,01). Conclusão: Embora os métodos propostos tenham apresentado concordância entre muitos dos parâmetros avaliados, os principais achados associados a processos infecciosos e inflamatórios como bacteriúria e leucocitúria, comuns no exame de urina, precisam ser mais bem investigados. Além disso, é importante que, de acordo com a metodologia empregada, o tempo de processamento e a logística técnica/laboratorial sejam adequados.

Objective: Evaluate the conformity between sediment method suggested by Brazilian Association of Technical Norms and another method suggest by Brazilian Society of Clinical Pathology Laboratory Medicine. Methods: It was used urine from nine people, obtaining 72 samples analyzed by both methods. Four different researchers examined each sample. The conformity between these methods was measured by the Pearson correlation coefficient for continuous variables and kappa concordance coefficient for the category variables. Results: There was concordance between methods for quantification of leukocyte casts (97.2%, κ = 0.61, p < 0.01), calcium oxalate crystals presence (77.8%, κ = 0.43, p = 0.04), hyaline casts (88.9%, κ = 0.51, p = 0.04), amorphous urate crystals (83.3%, κ = 0.59, p = 0.03), mucus (83.3%, κ = 0.48, p = 0.04) and yeast (75.9%, κ = 0.54, p = 0.04). These methods had moderate correlation for erythrocytes number (r = 0.56, p = 0.04) and epithelial cells (r = 0.73, p = 0.04). It is still worth noting SBPC/ML method requests a larger processing time (23.4 minutes) when compared to ABNT NBR 15268 (16.6 minutes, p < 0.01). Conclusion: Although the proposed methods had presented conformity at the evaluate parameters, the most important results associated to infection and inflammatory processessuch as bacteriuria and leukocyturia, common at urine exams, need to b e more studied. Thus, it is important that, according to the used methodology, the processing time and technical/laboratory logistic needs to be adequate

Hemoglobinuria paroxística nocturna. el rol de la anhidrasa carbónica-i urinaria en la hemólisis intravascular / Peroxysmal nocturnal hemoglobinuria: the role of urinary carbonic anhydrase-I in intravascular haemolysis

La Hemoglobinuria Paroxística Nocturna (HPN) se caracteriza por hemólisis intravascular crónica mediada por complemento. Cuando se produce la hemolisis se libera a circulación Anhidrasa Carbónica- I (AC-I), una enzima que se halla en alta concentración en el eritrocito y por su bajo peso molecular filtra por el glomérulo. El objetivo del presente trabajo fue detectar la excreción de la AC-I en orina de pacientes con HPN por Electroforesis Bidimensional de Utilidad Clínica (2D UC), y compararla con otras causas de hemólisis, de origen renal y postrenal. Se evaluaron 8 pacientes con HPN sin tratamiento con eculizumab un inhibidor del C5 del complemento, y 5 de ellos postratamiento, 12 orinas de pacientes con nefritis lúpica y 10 orinas de pacientes con hemólisis postrenal. La AC-I puede estar presente en la orina, en los tres grupos, sin embargo la relación AC-I/Hemoglobina en la hemólisis intravascular está invertida en comparación con la hemolisis glomerular y post-renal. Los pacientes con HPN tratados con eculizumab no presentan AC-I, y sería de utilidad en el seguimiento de los pacientes tratados con el inhibidor del C5, para evidenciar posibles escapes hemolíticos.

Paroxysmal Nocturnal Hemoglobinuria (PNH) is characterized by chronic complement mediated haemolysis. In these conditions it might be expected that carbonic anhydrase-I (AC-I) would be liberated into the plasma and excreted in the urine, by its high concentration in the erythrocyte and low molecular weight. The objective of the present study was to detect the urinary excretion of AC-I from patients with PNH by wodimensional clinical utility electrophoresis (2D UC) and to compare it with other causes of renal and post-renal haemolysis. We evaluated 8 patients with PNH without eculizumab, a complement C5 inhibitor, 5 of them posttreatment, 12 urine of patients with lupus nephritis and 10 urine of patients with post-renal hemolysis. AC-I may be present in the urine, in all three groups, however, the AC-I/Haemoglobin ratio in intravascular haemolysis is reversed compared to glomerular and post-renal haemolysis. Patients with PNH treated with eculizumab do not have AC-I and would be useful in monitoring patients treated with the C5 inhibitor to evidence possible haemolytic leaks.

Performance of the dipstick screening test as a predictor of negative urine culture / Desempenho da fita de urina como resultado presuntivo para cultura de urina negativa

ABSTRACT Objective To investigate whether the urine dipstick screening test can be used to predict urine culture results. Methods A retrospective study conducted between January and December 2014 based on data from 8,587 patients with a medical order for urine dipstick test, urine sediment analysis and urine culture. Sensitivity, specificity, positive and negative predictive values were determined and ROC curve analysis was performed. Results The percentage of positive cultures was 17.5%. Nitrite had 28% sensitivity and 99% specificity, with positive and negative predictive values of 89% and 87%, respectively. Leukocyte esterase had 79% sensitivity and 84% specificity, with positive and negative predictive values of 51% and 95%, respectively. The combination of positive nitrite or positive leukocyte esterase tests had 85% sensitivity and 84% specificity, with positive and negative predictive values of 53% and 96%, respectively. Positive urinary sediment (more than ten leukocytes per microliter) had 92% sensitivity and 71% specificity, with positive and negative predictive values of 40% and 98%, respectively. The combination of nitrite positive test and positive urinary sediment had 82% sensitivity and 99% specificity, with positive and negative predictive values of 91% and 98%, respectively. The combination of nitrite or leukocyte esterase positive tests and positive urinary sediment had the highest sensitivity (94%) and specificity (84%), with positive and negative predictive values of 58% and 99%, respectively. Based on ROC curve analysis, the best indicator of positive urine culture was the combination of positives leukocyte esterase or nitrite tests and positive urinary sediment, followed by positives leukocyte and nitrite tests, positive urinary sediment alone, positive leukocyte esterase test alone, positive nitrite test alone and finally association of positives nitrite and urinary sediment (AUC: 0.845, 0.844, 0.817, 0.814, 0.635 and 0.626, respectively). Conclusion A negative urine culture can be predicted by negative dipstick test results. Therefore, this test may be a reliable predictor of negative urine culture.

RESUMO Objetivo Verificar se a triagem de urina por fitas reativas é capaz de predizer a cultura de urina. Métodos Estudo retrospectivo realizado entre janeiro e dezembro de 2014 com 8.587 pacientes, com solicitação médica de triagem de urina (fita), sedimento urinário e cultura de urina. Foram analisados sensibilidade, especificidade, valor preditivo positivo, valor preditivo negativo e curva ROC. Resultados Foram positivas 17,5% das culturas. O nitrito apresentou sensibilidade de 28% e especificidade de 99%. O valor preditivo positivo foi de 89% e o valor preditivo negativo de 87%. Esterase apresentou sensibilidade de 79% e especificidade de 84%. Valor preditivo positivo e valor preditivo negativo foram de 51% e 95%, respectivamente. A combinação de nitrito ou esterase positivos apresentou sensibilidade de 85% e especificidade de 84%. Valor preditivo positivo e valor preditivo negativo foram, respectivamente, 53% e 96%. O sedimento positivo (mais de dez leucócitos por microlitro) apresentou sensibilidade de 92% e especificidade de 71%. O valor preditivo positivo foi 40% e o negativo, 98%. A combinação de nitrito e sedimento urinário positivos apresentou sensibilidade de 82% e especificidade de 99%. Os valores preditivos positivo e negativo foram 91% e 98%, respectivamente. Para o nitrito ou esterase positivos mais os leucócitos positivos, a sensibilidade foi de 94% e a especificidade de 84%. O valor preditivo positivo foi de 58% e o negativo foi de 99%. Com base na curva ROC, o melhor indicador de urocultura positiva foi a associação entre a esterase ou nitrito positivos na fita mais os leucócitos positivos no sedimento, seguido por nitrito e esterase positivos, sedimento urinário positivo isolado, esterase positiva isolada, nitrito positivo isolado e, finalmente, pela associação entre nitrito e sedimento urinário positivos (AUC: 0,845, 0,844, 0,817, 0,814, 0,635 e 0,626, respectivamente). Conclusão Uma urocultura negativa pode ser prevista com resultados negativos na fita. Portanto, este teste pode ser um preditor confiável de urocultura negativa.

Dipstick spot urine pH does not accurately represent 24 hour urine PH measured by an electrode

ABSTRACT Objectives To determine whether spot urine pH measured by dipstick is an accurate representation of 24 hours urine pH measured by an electrode. Materials and Methods We retrospectively reviewed urine pH results of patients who presented to the urology stone clinic. For each patient we recorded the most recent pH result measured by dipstick from a spot urine sample that preceded the result of a 24-hour urine pH measured by the use of a pH electrode. Patients were excluded if there was a change in medications or dietary recommendations or if the two samples were more than 4 months apart. A difference of more than 0.5 pH was considered an inaccurate result. Results A total 600 patients were retrospectively reviewed for the pH results. The mean difference in pH between spot urine value and the 24 hours collection values was 0.52±0.45 pH. Higher pH was associated with lower accuracy (p<0.001). The accuracy of spot urine samples to predict 24-hour pH values of <5.5 was 68.9%, 68.2% for 5.5 to 6.5 and 35% for >6.5. Samples taken more than 75 days apart had only 49% the accuracy of more recent samples (p<0.002). The overall accuracy is lower than 80% (p<0.001). Influence of diurnal variation was not significant (p=0.588). Conclusions Spot urine pH by dipstick is not an accurate method for evaluation of the patients with urolithiasis. Patients with alkaline urine are more prone to error with reliance on spot urine pH.

Alto rendimiento clínico entre albuminuria semicuantitativa y proteinuria de 24 horas en pacientes con sospecha de síndrome hipertensivo del embarazo / High clinical performance between semiquantitative albuminuria and 24-hour proteinuria in patients with suspected hypertensive syndrome of pregnancy

ANTECEDENTES: La evaluación precisa de la proteinuria constituye un pilar importante para el diagnóstico del síndrome hipertensivo del embarazo (SHE). El estándar dorado para esta medición es la recolección de orina en 24 horas, pero debido a la duración de la toma de la muestra, alternativas como la albuminuria semicuantitativa se utiliza con mayor frecuencia en los servicios de urgencia de nuestro país. OBJETIVO: Evaluar el rendimiento diagnóstico de la albuminuria semicuantitativa y su asociación con proteinuria de 24 horas en pacientes con SHE. MÉTODOS: Estudio retrospectivo de 145 pacientes con sospecha de SHE atendidas en el Hospital Padre Hurtado, Chile. A todas las pacientes se le realizó albuminuria semicuantitativa (categorizada entre 0+ y 4+) y proteinuria de 24 horas (positivo si >0,3 gramos/24 horas). Se realizó análisis por grupos compuestos de albuminuria semicuantitativa y resultado positivo en proteinuria de 24 horas. RESULTADOS: Se evidenció una sensibilidad de 50%, especificidad de 100%, VPP de 100%, VPN de 65,7%, LR+ de 50 y un LR- de 0,5. CONCLUSIÓN: La albuminuria semicuantitativa ≥2+ muestra una fuerte asociación con proteinuria ≥0,3 g/24 horas y es un método rápido para evaluar SHE.

BACKGROUND: One of the basis for the diagnosis of pregnancy induced hypertension syndrome (PIHS), includes the precise evaluation of proteinuria. The gold standard for its evaluation is the collection of a 24-hour urine specimen, but because it is a slow method, other alternatives, such as semi-quantitative albuminuria have been used more frequently on our emergency rooms. OBJECTIVE: To assess the diagnostic performance of semi-quantitative albuminuria and its association with proteinuria measured in a 24-hour urine specimen collection, in patients with PIHS. METHODS: Retrospective study of 145 patients with clinical suspicion of PIHS who assisted to Hospital Padre Hurtado, Chile. Semi-quantitative albuminuria (categorized as 0 to 4+) and proteinuria measured in a 24-hour urine specimen collection was measured on every patient. Abnormal values of proteinuria were considered when values exceeded 0.3 g/24 hours. Composite outcomes analysis was done between albuminuria groups and positive proteinuria in 24 hrs. RESULTS: Sensibility and specificity of semi-quantitative albuminuria was of 50% and 100%, respectively, with a PPV: 100%, NPV: 65.7%, LR+: 50 and a LR-: 0.5. CONCLUSION: semi-quantitative albuminuria ≥2+ shows a strong association with proteinuria ≥0.3 g/24 hours and it could be used as a fast method to assess PIHS.

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.

Value of color doppler ultrasound, kub and urinalysis in diagnosis of renal colic due to ureteral stones

Purpose Despite the routine use of helical CT in diagnosis of renal colic, there are recent concerns regarding the radiation exposure, overuse and costs. We attempted in this retrospective study to evaluate the accuracy of ultrasound (gray-scale and color Doppler with twinkling), KUB and urinalysis in diagnosis of renal colic due to ureteral calculi presented in Emergency Room. Materials and Methods A total of 939 consecutive cases of renal colic presented to ER have been managed and evaluated by ureteral ultrasound, KUB and urinalysis for the presence of ureteral stones. Non-confirmatory cases were subjected to Helical CT examination. Results Renal and ureteral ultrasound (gray-scale) alone detected ureteral calculi in 615 cases (65.4%) and after utilizing Color Doppler Ultrasound with twinkling the diagnosis was made with confidence in 935 cases (99.6%) but 4 (0.4%). KUB showed radiopaque stones in 503 (53.6%) patients and no stones were detected in 436 (46.4%). Microhematuria presented in 835 (88.9%) cases while absent in 102 (10.9%). There were 190 (20.3%), 77 (8.2%) and 671 (71.5%) patients with upper, middle and lower ureteral stones respectively. The simultaneous positive findings in US and KUB with microhematuria were found only in 453 (48.2%) cases. Conclusions The use of Color Doppler ultrasound with twinkling increased the detection rate of ureteral stones in acute renal colic patients presented to ER with less radiation exposure. Ultrasound examination as a single modality is superior to KUB and urinalysis in initial diagnosis of renal colic. .

Comparison of urine analysis using manual and sedimentation methods / Comparación del análisis de orina usando el método manual y el método de sedimentación

OBJECTIVE: Microscopic examination of urine sediment is an essential part in the evaluation of renal and urinary tract diseases. Traditionally, urine sediments are assessed by microscopic examination of centrifuged urine. However, the current method used by the Georgetown Public Hospital Corporation Medical Laboratory involves uncentrifuged urine. To encourage high level of care, the results provided to the physician must be accurate and reliable for proper diagnosis. The aim of this study is to determine whether the centrifuge method is more clinically significant than the uncentrifuged method. METHODS: In this study, a comparison between the results obtained from centrifuged and uncentrifuged methods were performed. A total of 167 urine samples were randomly collected and analysed during the period April-May 2010 at the Medical Laboratory, Georgetown Public Hospital Corporation. The urine samples were first analysed microscopically by the uncentrifuged, and then by the centrifuged method. The results obtained from both methods were recorded in a log book. These results were then entered into a database created in Microsoft Excel, and analysed for differences and similarities using this application. Analysis was further done in SPSS software to compare the results using Pearson's correlation. RESULTS: When compared using Pearson's correlation coefficient analysis, both methods showed a good correlation between urinary sediments with the exception ofwhite bloods cells. The centrifuged method had a slightly higher identification rate for all of the parameters. CONCLUSIONS: There is substantial agreement between the centrifuged and uncentrifuged methods. However, the uncentrifuged method provides for a rapid turnaround time.

OBJETIVO: El examen microscópico del sedimento de orina es una parte esencial en la evaluación de enfermedades renales y del tracto urinario. Tradicionalmente, los sedimentos de orina son evaluados mediante examen microscópico de orina centrifugada. Sin embargo, el método actual usado por el Laboratorio Médico de la Corporación del Hospital Público de Georgetown recurre a la orina no centrifugada. Con el propósito de estimular un alto nivel de cuidado, los resultados proporcionados al médico tienen que ser exactos y fiables para un diagnóstico apropiado. El objetivo de este estudio es determinar si el método de la centrifugación es clinicamente más significativo que el método sin centrifugación. MÉTODOS: En este estudio, se hace una comparación entre los resultados obtenidos a partir del método con centrifugado y sin centrifugado. Un total de 167 muestras de orina fueron recogidas aleatoriamente y analizadas durante el periodo de abril a mayo de 2010 en el Laboratorio Médico de la Corporación del Hospital Público de Georgetown. Las muestras de orina se analizaron primero microscópicamente por el método sin centrifugado, y entonces por el método con centrifugación. Los resultados obtenidos mediante ambos métodos fueron registrados en un en un diario de documentación. Estos resultados fueron entonces introducidos en un banco de datos creado en Microsoft Excel, y analizados en cuanto a sus diferencias y similitudes usando esta aplicación. El análisis se realizó también más tarde mediante el software de SPSS para comparar los resultados usando la correlación de Pearson. RESULTADOS: Al ser comparados mediante análisis basado en el coeficiente de correlación de Pearson, ambos métodos mostraron una buena correlación de los sedimentos urinarios, con excepción de los leucocitos. El método de la centrifugación tuvo una tasa de identificación ligeramente más alta para todos los parámetros. CONCLUSIONES: Existe una correspondencia sustancial entre los métodos con centrifugado y sin centrifugado. Sin embargo, el método que no emplea la centrifugación ofrece un tiempo de respuesta más rápido.

Análise comparativa de duas metodologias para a identificação de cilindros hemáticos urinários / Comparative analysis of two methodologies for the identification of urinary red blood cell casts

INTRODUÇÃO: A presença de hemácias dismórficas na urina é um forte indicativo da origem glomerular do sangramento, sendo uma ferramenta importante no diagnóstico de glomerulonefrites. Os cilindros hemáticos geralmente acompanham as hemácias dismórficas, sendo também fortes indicadores de hematúria glomerular, embora não sejam encontrados com frequência no exame parcial de urina. OBJETIVO: Comparar duas técnicas de concentração de amostras em uma série de exames de urina com hematúria dismórfica. MATERIAL E MÉTODOS: Foram selecionadas 249 amostras com hematúria dismórfica a partir de 4.277 amostras de urina de rotina. As amostras foram processadas utilizando-se duas técnicas: a convencional e a de concentração. O percentual de identificação dos cilindros hemáticos foi comparado de acordo com a metodologia utilizada. RESULTADOS: A presença de cilindros hemáticos pela técnica de concentração foi estatisticamente maior (52,6 por cento) em comparação com a positividade pela metodologia convencional (8,4 por cento) (p < 0,001). DISCUSSÃO E CONCLUSÃO: Sugere-se que a técnica convencional não concentrou suficientemente a amostra de urina e os cilindros hemáticos ficaram no sobrenadante, sendo descartados. A utilização da técnica de concentração aumentou a sensibilidade técnica para a pesquisa dos cilindros hemáticos. Portanto, a técnica de concentração, associada à presença de hemácias dismórficas, mostrou-se útil para aumentar a concordância dos dois parâmetros laboratoriais para a detecção da hematúria de origem glomerular como auxílio diagnóstico das glomerulopatias, importante causa de doença renal crônica.

INTRODUCTION: Dysmorphic red blood cells (RBCs) in the urine are a strong indicator of a glomerular bleeding source. RBC casts, which while generally following RBC dysmorphism are not frequently seen on routine urinalysis, are also important indicators of glomerular hematuria. OBJECTIVE: This study tested the superiority of a urine concentration technique (CT) over the standard method (SM) for RBC cast identification in a group of patients suspected of glomerular hematuria. MATERIAL AND METHODS: Of a total of 4,227 routine urinary samples, 249 with dysmorphic hematuria were selected. The samples were processed according to two techniques: standard method (SM) and concentration technique (CT). The percentages of RBC cast identification according to each method were compared. RESULTS: The CT showed a higher rate of RBC casts (52.6 percent) compared to the SM (8.4 percent) (p < 0.001). DISCUSSION AND CONCLUSION: We suggest that the SM did not sufficiently concentrate the urine sample, the RBC casts remaining in the supernatant and being discarded. The CT increased the sensitivity of the RBC cast yield. The CT, associated with the presence of RBC dysmorphism, was useful to increase the agreement of the two parameters used for identification of glomerular-based bleeding and the diagnosis of glomerular diseases, important causes of chronic kidney disease.

Urinary parameters of Trichechus inunguis (Mammalia, Sirenia): reference values for the Amazonian Manatee / Parâmetros urinários de Trichechus Inunguis (Mammalia, Sirenia): valores-referência para o peixe-boi da Amazônia

The Amazonian manatee, Trichechus inunguis (Natterer 1883) is endemic to the Amazon Basin and is currently considered a vulnerable species. In order to establish normality ranges of urinary parameters to help monitor the health of this species in captivity, chemical urinalyses were performed on twelve males and nine females of various age groups. Urine was collected once a month for twelve months in the tanks just after being drained, by placing stainless steel containers under the genital slit of females and applying abdominal massages to males in order to stimulate urination. Quantitative data of glucose, urea, creatinine, uric acid and amylase levels were obtained using colorimetric spectrophotometry. Dip strips were also useful for routine analyses, despite only providing qualitative results. Normal range to glucose levels, regardless of sex or age class, was 3.0 to 3.6 mg.dL-1, coinciding with qualitative values of glucose measured by dip strips. Statistical differences observed in some parameter levels suggest that some urine parameters analysed must take into consideration the sex and the age class of the animal studied, being these differences less remarkable in creatinine and amylase levels. To this last one, statistical difference was detected only in the calve's urine (7.0 to 11.5 mg.dL-1) compared to other age classes samples (4.1 to 5.3 mg.dL-1). The results presented here may be used as comparative data in future research on urinalysis in related species.

O peixe-boi da Amazônia, Trichechus inunguis (Natterer 1883) é endêmico da Bacia Amazônica e é considerado atualmente como espécie vulnerável. Com o objetivo de estabelecer valores de normalidade para os parâmetros urinários com vistas a ajudar no monitoramento da saúde desta espécie em cativeiro, foi realizada urinálise química em doze machos e nove fêmeas de várias classes etárias. A urina era coletada uma vez por mês, durante doze meses, nos tanques, logo após esvaziamento, colocando-se coletores de aço inoxidável sob o orifício genital das fêmeas e aplicando massagem abdominal nos machos para estimular a micção. Dados quantitativos dos níveis de glicose, ureia, creatinina, ácido úrico e amilase foram obtidos por meio de espectrofotometria colorimétrica. O uso de tiras reativas também foi útil para análises de rotina, apesar de somente fornecerem resultados qualitativos. A faixa de normalidade para os níveis de glicose, independente de classe etária e sexo foi de 3,0 a 3,6 mg.dL-1, coincidindo com os valores qualitativos identificados pelas tiras reativas. Diferenças estatísticas observadas nos níveis de alguns parâmetros analisados sugerem que estes devem levar em consideração o sexo e a classe etária do animal estudado. Estas diferenças foram menos marcantes nos níveis de creatinina e de amilase, sendo que para esta última foi detectada diferença estatística apenas nas urinas de filhotes lactentes (7,0 a 11,5 mg.dL-1), em comparação às amostras das demais classes etárias (4,1 a 5,3 mg.dL-1). Os resultados aqui apresentados podem ser usados como dados comparativos em futuras pesquisas sobre urinálise em espécies relacionadas.

Benefits of urinalysis.

Objective. In the pilot Iran school screening programme, the minimal cost of screening dipstick urinalysis in 1601 asymptomatic school children was determined. Methods. The cost of screening dipstick urinalysis was calculated by reviewing the literature for the prevalence of asymptomatic proteinuria, hematuria, bacteriuria, and glucosuria determined by an initial dipstick urinalysis.The minimal cost utilizing data of 3 general physicians was calculated. Costs were determined by using current charge for supplies ordered to perform tests, charges for tests performed by a commercial laboratory, and the cost of a final evaluation by a pediatric nephrologist. Results. 4.7% (76/1601) of patients were calculated to have an initial abnormal urinalysis. Upon retesting 1.37% (22/1601) of patients were calculated to have a persistent abnormality. The calculated cost was 167$ to initially screen all 1601pateints with a dipstick urinalysis or 0.092$ per patient. The calculated cost to evaluates the 22 patients with any persistent abnormality on repeat dipstick urinalysis was 0.02$ or 0.001$ per patient. This is the calculated cost for a single screening of 1601 asymptomatic pediatric patients. Conclusion. Multiple screening dipstick urinalysis in asymptomatic pediatric is costly and should be discontinued. We propose that a single screening dipstick urinalysis be obtained at school entry age, between 6 and 7 years, in all asymptomatic children.

Infecção do trato urinário na gravidez: aspectos diagnósticos, terapêuticos e prognósticos / Urinary tract infection in pregnancy: diagnostic, therapeutic and prognostic aspects

Infecção do trato urinário é complicação comum na gravidez devido às mudanças anatômicas e funcionais, sendo responsável por elevado número de complicações mateno-fetais. Em decorrência de sua importância, o presente trabalho faz atualização das recentes evidências quanto ao manejo dessa afecção. Ao final do primeiro trimestre, recomenda-se a triagem para bacteriúria asintomática em todas as gestantes. Mulheres com bacteriúria assintomática ou infecção urinária sintomática durante a gravidez devem ser tratadas e submeterem-se a screenings periódicos durante toda a gestação. Os beta-lactâmicos são os antibióticos de escolha para o tratamento dessas gestantes. Evidências sugerem uso de terapia oral por três a sete dias para cistite e parenteral de 14 dias para pielonefrite. As pacientes devem realizar urocultura de controle com 48 ou 72 horas de tratamento. A profilaxia é indicada em casos especívicos em dose única pós-coital ou diariamente com cefalexina ou nitrofurantoína. O presente artigo ainda discute a conduta em situações especiais, como em pacientes com litíase renal, traço falcêmico e ureterossigmoidostomia.

Urinary tract infection is a common complication of pregnancies due to functional, anatomic and hormonal changes. Given its importance, this current article reviews the current evidence on handling of this illness. At the end of the first trimester, a screening for asymptomatic bacteriuria is recommended for all pregnant women. The ones with asymptomatic bacteriuria or symptomatic UTI during childbearing should be treated and submitted to periodical screenings during all gestation period. The beta-lactams are the antibiotics chosen for the treatment of these pregnant women. Evidence suggests the use of 3 to 7 day oral therapy against cystitis and 14 day parenteral therapy against pielonefhritis. The patients should undergo urine culture within 48 or 72 hours of treatment. The single dose prophylaxis is indicated in specific cases after coitus or on a daily basis with the prescription of cephalexin or nitrofurantoin. This article still discusses the management in special situations, such as renal lithiasis, ureterossigmoidostomy and sickling trace.

Evaluation of 8-hour and 12-hour urine collection for detection of proteinuria in hypertensive women, Shariati hospital, 2004-2005

Hypertensive disorders are common during pregnancy. Combination of hypertension and proteinuria markedly increase prenatal morbidity and mortality. The gold standard method for proteinuria assessment is 24-hour urine collection. This survey is designed to determine the correlation between protein content of 8-hour and 24-hour urine collections. This cross-sectional study was conducted on 65 pregnant women with gestatinal age of over-20 weeks who were admitted for assessment of proteinuria in obstetrics section of Shariati hospital, Bandar Abbas. Four urine samples were collected from each patient including random sample, 8, 12 and 24-hour samples. Randoms sample was examined qualitatively while other samples were assessed quantitatively. Data were analyzed by Minitab software. Pearson's correlation coefficient of 8-hour and 12-hour samples with 24-hour was calculated. Sensitivity, specificity, negative and positive predictive values of random, 8-hour and 12-hour samples were also determined. Pearson's correlation coefficients of 8-hour with 24-hour and 12-hour with 24-hour were 0.873 [P<0.01] and 0.89 [P<0.01], respectively. 8-hour sample had a sensitivity of 63%and negative predictive value of 82%. The 12-hour and random samples predicted significant proteinuria with a sensitivity of 82% and 75%, specificity of 88% and 63%, positive predictive values of 85% and 62%, and negative predictive values of 86% and 76%, respectively. All patients with proteinuria in 8-hour and 12-hour samples had significant proteinuria in 24-hour sample. There is a strong correlation between 8-hour and 12-hour with 24-hour urine protein levels. Either the simultaneous positive or negative result for proteinuria in 8-hour, 12-hour and random samples is of great significance in documentation or ruling out of proteinuria in 24-hour sample collection

Evaluation of urinalysis parameters to predict urinary-tract infection

We evaluated the performance of automated-flow cytometry, urinalysis dipsticks and microscopic urine sediment analysis as predictors of urinary tract infection. Urine cultures were used as a reference method for comparison. Six-hundred-seventy-five urine samples from hospitalized and not hospitalized patients attended at Hospital Mãe de Deus, Porto Alegre, in south Brazil, were included in the study. Among the individual measures analyzed, intense bacteriuria in the microscopic analysis of urinary sediment gave an accuracy of 92.9 percent. A combination between intense bacteriuria (microscopic analysis) and >20 leukocytes per µL of urine (flow cytometry) gave a higher accuracy (97.3 percent). We conclude that though it is laborious, microscopic urinalysis is a good analytical tool. Taken together with flow cytometry and dipsticks, we obtained a clinically-acceptable prediction of urinary-tract infection.

Spot urinary protein/osmolality ratio as a predictor for proteinuria of nephrotic range.

A prospective study was carried out on 50 patients (age 1-15 years) with nephrotic range of proteinuria to determine the correlation of 24-hour urinary total protein with spot urinary protein/creatinine ratio and urinary protein/osmolality ratio. Another 50 patients having no proteinuria grouped as control. Twenty-four hours urine and spot urine were collected from each child and were analyzed for total volume, total protein, creatinine and osmolality level. The average 24-hour urinary total proteins in nephritic patient were 2148.6 +/- 808.7 mg and the spot urinary protein/creatinine and spot urinary protein/osmolality were 3.2332 +/- 0.4293 mg/mg and 3.2418 +/- 0.4393 mg/mOsm respectively. There was a strong positive correlation of the 24-hour urinary total protein with spot urinary protein/creatinine and protein/osmolality ratios (r=0.9846 and 0.9870, p= <0.001). But in control group, these ratios did not show any correlation with 24-hour urinary total protein. These results suggest that in pediatric patients with nephrotic range of proteinuria, the spot urinary protein/osmolality ratio can predict the 24-hour urinary total protein excretion like that of spot urinary protein/creatinine ratios.