Windows to the Ward: Graphically Oriented Report Forms. Presentation of Complex, Interrelated Laboratory Data for Electrophoresis/Immunofixation, Cerebrospinal Fluid, and Urinary Protein Profiles

Regeniter, Axel; Steiger, Jürg; Scholer, André; Huber, Peter; Siede, W

doi:10.1373/49.1.41

Cited by 16 publications

(4 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Mediante el uso de programas informáticos se simplifica el flujo de datos, permitiendo una mayor automatización del laboratorio y ofreciendo posibilidades de interpretación de los resultados para los clínicos. Con la estrategia diagnóstica propuesta, la información obtenida a partir de un análisis de orina aumenta notablemente, y esto mejora la calidad ofrecida por el laboratorio (8).…”

Section: Discussionunclassified

Implantación en el laboratorio de un algoritmo para el diagnóstico diferencial de la proteinuria

Otón

Cueva

Lopez

et al. 2005

An. Med. Interna (Madrid)

View full text Add to dashboard Cite

INTRODUCCIÓNEl análisis de anormales y sedimento en orina es una de las pruebas más comúnmente solicitadas al laboratorio clíni-co, siendo de gran utilidad en el diagnóstico precoz de la enfermedad renal. Con frecuencia, ésta se acompaña del hallazgo ocasional de proteinuria en un análisis sistemático de orina, lo que puede preceder incluso en años a otros signos de enfermedad renal, como la elevación de creatinina plasmática. Además, la proteinuria es un factor de riesgo [0212-7199 (2005) RESUMENFundamento y objetivo: El hallazgo de proteinuria debe ir seguido de un diagnóstico diferencial para determinar su origen. Nuestro objetivo ha sido valorar los resultados de la implantación por el laboratorio de un algoritmo para el cribado y diagnóstico de la proteinuria.Material y métodos: De un total de 30.718 orinas procesadas, se obtuvo una concentración de proteínas igual o superior a 30 mg/dl en 639, recomendándose el envío de una nueva muestra para confirmación y estudio diferencial de proteinuria. Se recibieron 207, a las que, además de las proteínas totales, se les cuantificaron creatinina, albúmina y alfa-1-microglobulina, junto con los parámetros de la tira reactiva pseudoperoxidasa y esterasa leucocitaria. Estos resultados se incorporaron a un sistema experto (UPES y su aplicación Protis), que permite la diferenciación de hematuria, leucocituria y proteinuria, solicitando la medida de otras pruebas (IgG, alfa-2-macroglobulina, cadenas ligeras kappa/lambda) cuando es necesario.Resultados: De las 207 peticiones recibidas para estudio de proteinuria selectiva, 39 fueron normales, 96 se clasificaron como glomerulopatía primaria, 26 como glomerulopatía secundaria y 5 como nefropatía túbu-lo-intersticial. Se pudo diferenciar el origen de la hematuria en 58 de estas orinas. Además, detectamos cadenas ligeras libres tipo kappa, confirmadas por inmunofijación, en una muestra de orina de un paciente con un proteinograma normal en suero.Conclusión: Con el algoritmo propuesto, la información obtenida de una muestra de orina aumenta mucho, permitiendo la detección y diferenciación de la proteinuria y aportando sugerencias para la evaluación clínica del paciente.

show abstract

Section: Discussionunclassified

Implantación en el laboratorio de un algoritmo para el diagnóstico diferencial de la proteinuria

Otón

Cueva

Lopez

et al. 2005

An. Med. Interna (Madrid)

View full text Add to dashboard Cite

show abstract

“…MDI-LabLink, developed by Regeniter et al (4 ), screens for proteinuria with few marker proteins (albumin and A1M) but uses additional marker proteins (IgG, transferrin, RBP, and ␤ 2 -microglobulin) to enable comparison with the SDS-polyacrylamide gel electrophoresis (PAGE) classification system introduced by Boesken et al (12,13 ). It also evaluates the numerous formulas specific to quantitative measurement to further classify proteinuria (4,(12)(13)(14)(15)(16) and transforms results to a specific signature pattern (17 ).…”

mentioning

confidence: 99%

“…Most importantly (25,26 ), it quantifies the amount of renal damage and converts the different reference intervals of the urinary marker proteins to a graphic result signature pattern (Fig. 1B), which provides instant understanding of a complex biochemical situation (17 ). We found this to be an investigator-independent and standardized approach superior in evaluating proteinuria and have replaced SDS electrophoresis with the protein marker approach in our laboratory.…”

mentioning

confidence: 99%

Patterns of Proteinuria: Urinary Sodium Dodecyl Sulfate Electrophoresis Versus Immunonephelometric Protein Marker Measurement Followed by Interpretation with the Knowledge-Based System MDI-LabLink

et al. 2004

Self Cite

View full text Add to dashboard Cite

Increased urinary total protein is a nonspecific and unreliable marker of renal function. Analysis of the pattern of proteinuria, however, can provide information regarding the pathophysiologic changes in the affected nephrons. In physiologic proteinuria, the range of daily urinary protein excretion is typically 40 -80 mg/24 h with an upper limit of 150 mg/24 h. Albumin represents the main component (30 -40%), whereas IgG, light chains, and IgA represent 5-10%, 5%, and 3%, respectively, of urinary proteins. The remainder consists mostly of Tamm-Horsfall protein.Patterns of pathologic proteinuria may be classified as glomerular, tubular, prerenal, mixed, or postrenal, with glomerular patterns the most frequent. Total urine protein excretion can exceed 2 g/day, with albumin representing the main component (ϳ70%) and other large-molecularweight proteins, such as transferrin and IgG, accounting for the remaining 30%. Tubular proteinuria is characterized by the dominant excretion of low-molecular-weight proteins such as ␣ 1 -microglobulin (A1M) or retinol-binding protein (RBP), which correlate better with the extent of tubulo-interstitial damage than does determination of total 24-h protein concentrations (1 ).Urinary total protein is frequently undetectable in predominantly tubular kidney disease, and common chemical methods also often fail to detect urinary total protein in predominantly tubular kidney disease, in which albumin usually represents Ͻ30% of the total protein content (2-8 ). However, some renal tubular disorders or interstitial nephritis (e.g., when caused by antibiotics and other tubulo-toxic substances) are easily treatable. Prerenal proteinuria (Bence Jones proteinuria), attributable to overproduction of light chains in monoclonal diseases, or lysozymuria in patients with leukemia and the resulting overload of tubulo-interstitial reabsorption in the kidney often lead to secondary kidney damage. Mixed proteinuria presents with glomerular and tubular protein fractions in urine, i.e., high-and low-molecular-weight proteins. Postrenal proteinuria closely resembles glomerular proteinuria but can be identified by the presence of ␣ 2 -macroglobulin.Early approaches to the evaluation of proteinuria were based on sodium dodecyl sulfate (SDS) electrophoresis (9, 10 ). This method, however, is time-consuming, is at best semiquantitative, and has a high analytical detection limit well above the reference interval for most protein bands (Ϸ20 mg/L), and interpretation is investigator dependent. Alternatively, urinary marker proteins can be measured quantitatively by immunoturbidimetry or nephelometry.At least two knowledge-based systems for the further evaluation of proteinuria are available, UPES (11 ) and MDI-LabLink (4 ). MDI-LabLink, developed by Regeniter et al. (4 ), screens for proteinuria with few marker proteins (albumin and A1M) but uses additional marker proteins (IgG, transferrin, RBP, and ␤ 2 -microglobulin) to enable comparison with the SDS-polyacrylamide gel electrophoresis (PAGE) classification s...

show abstract

“…The proteinuria is typed by quantitative (nephelometry) (16,17 ) and qualitative (immunofixation) (18 ) immunologic techniques and by sodium dodecyl sulfate-agarose gel electrophoresis (SDS-AGE) (19 ), with retinol-binding protein (21 kDa) and ␣ 1 -microglobulin (31 kDa) considered as markers of tubular damage; albumin (67 kDa), transferrin (80 kDa), and IgG (150 kDa) as markers of glomerular injury; and ␣ 2 -macroglobulin (725 kDa) as a marker of postrenal proteinuria. In addition, we measure total urinary proteins by the biuret (20 ) and pyrogallol red assays.…”

mentioning

confidence: 99%

Presence of Protein Fragments in Urine of Critically Ill Patients with Acute Renal Failure: A Nephrologic Enigma

et al. 2004

View full text Add to dashboard Cite

Predicting complications in intensive care units (ICUs) is an important step in the care of critically ill patients. Intensive care specialists have developed numerous prognostication tools for patients admitted to the ICU; however, although useful, many of these tools are not applicable in a clinical setting, and multiple severity-of-illness scores often underestimate hospital mortality in several conditions (1, 2 ).Many acute pathologic states, such as burns, trauma, bleeding, and sepsis, are associated with the induction of a "systemic inflammatory response", which is characterized by the release of pro-inflammatory mediators and the activation of different types of cellular elements (3-6 ). This response primarily involves endothelial cells and leukocytes (7)(8)(9). It is possible to use renal function as an early marker for systemic illness because kidney involvement is a recognized complication of several systemic diseases. Acute renal failure (ARF), usually attributable to intrarenal hemodynamic changes, often complicates the clinical course of critically ill patients (10 -12 ). Microalbuminuria has been proposed as a marker of capillary leak severity in the ICU (13,14 ). It has previously been demonstrated that urinary albumin degrades into multiple fragments in meningococcal sepsis and that the quantity of degraded albumin is associated with severity (15 ).Since April 2003, we have analyzed untimed urine samples from critically ill patients with ARF in ICUs: dipstick test and urine sediment analysis were performed on all samples, and none showed massive leukocyturia. The proteinuria is typed by quantitative (nephelometry) (16, 17 ) and qualitative (immunofixation) (18 ) immunologic techniques and by sodium dodecyl sulfate-agarose gel electrophoresis (SDS-AGE) (19 ), with retinol-binding protein (21 kDa) and ␣ 1 -microglobulin (31 kDa) considered as markers of tubular damage; albumin (67 kDa), transferrin (80 kDa), and IgG (150 kDa) as markers of glomerular injury; and ␣ 2 -macroglobulin (725 kDa) as a marker of postrenal proteinuria. In addition, we measure total urinary proteins by the biuret (20 ) and pyrogallol red assays. All samples were stored at 4°C after centrifugation (400g for 5 min) and were analyzed within 3-24 h. Storage in a refrigerator (4°C) did not change the results.Here we report on 10 cases (9 males and 1 female; age range, 40 -79 years; 18.1% of all screened patients) with ARF in whom we found evidence of urinary protein degradation. All patients had a prerenal cause of ARF; only one patient was not oliguric and did not need renal replacement therapy. Five patients died, and five had renal function recovery.SDS-AGE performed at the time of the nephrologic visit and diagnosis revealed a smeared band of proteins and protein fragments, covering the molecular mass range between 10 and 300 kDa, and an absence of the typical bands for the single proteins.The SDS-AGE migration patterns of one of these patients on 3 consecutive days are shown in Fig. 1; after 24 and 48 h, the bands for albu...

show abstract

Windows to the Ward: Graphically Oriented Report Forms. Presentation of Complex, Interrelated Laboratory Data for Electrophoresis/Immunofixation, Cerebrospinal Fluid, and Urinary Protein Profiles

Cited by 16 publications

References 38 publications

Implantación en el laboratorio de un algoritmo para el diagnóstico diferencial de la proteinuria

Implantación en el laboratorio de un algoritmo para el diagnóstico diferencial de la proteinuria

Patterns of Proteinuria: Urinary Sodium Dodecyl Sulfate Electrophoresis Versus Immunonephelometric Protein Marker Measurement Followed by Interpretation with the Knowledge-Based System MDI-LabLink

Presence of Protein Fragments in Urine of Critically Ill Patients with Acute Renal Failure: A Nephrologic Enigma

Contact Info

Product

Resources

About