Accuracy of Two Point-of-Care Tests for Rapid Diagnosis of Bovine Tuberculosis at Animal Level using Non-Invasive Specimens.

Bovine tuberculosis (BTB) testing in cattle requires a significant investment of time, equipment, and labor. Novel, rapid, cheaper and accurate methods are needed. The Alere Determine TB lipoarabinomannan antigen (LAM-test) is a World Health Organization-endorsed point-of-care urine test designed to detect active TB disease in humans. The Lionex Animal TB Rapid Test (Lionex-test) is a novel animal specific TB diagnostic blood test. An animal level analysis was performed using urine (n = 141) and milk (n = 63) samples from depopulated BTB-suspected cattle to test the accuracy of the LAM-test when compared to results of positive TB detection by any routine BTB tests (BOVIGAM, necropsy, histology, culture, PCR) that are regularly performed by the United States Department of Agriculture (USDA). The agreement between the urine LAM-test and USDA standard tests were poor at varying testing time points. The same milk samples did not elicit statistically significant agreement with the Lionex-test, although positive trends were present. Hence, we cannot recommend the LAM-test as a valid BTB diagnostic test in cattle using either urine or milk. The Lionex-test's production of positive trends using milk samples suggests larger sample sizes may validate the Lionex-test in accurately diagnosing BTB in cattle using milk samples, potentially providing a quick and reliable field test for BTB.

Neumonía comunitaria por Legionella pneumophila: estudio de 136 casos / Community acquired pneumonia by Legionella pneumophila: Study of 136 cases

Objetivo: La mayoría de los datos de la neumonía por Legionella en nuestro país proceden del área mediterránea, y apenas existen estudios en la zona del Noroeste. Con este trabajo se pretende conocer la situación de la infección en nuestro medio. Método: Estudio retrospectivo de todos los pacientes con antigenuria positiva para Legionella en el Hospital Universitario Lucus Augusti de Lugo desde 2001, año en que se introdujo la antigenuria como prueba diagnóstica en nuestro centro, hasta 2015. Se analizaron datos epidemiológicos, factores de riesgo, hallazgos clínicos, radiológicos, analíticos y evolutivos. Resultados: Se registraron 136 pacientes. Si comparamos los primeros 5años del estudio con los 5últimos, la incidencia aumentó de 10,9 a 64,5 casos/1.000.000, el número de peticiones de antigenuria se incrementó 3,4 veces, y con respecto a otras neumonías, Legionella pasó del 0,9 al 15% de ellas. La edad media fue de 64,1años, y el 84,6% fueron varones. El 74,3% tenían comorbilidades. Los varones fueron significativamente más jóvenes (62,7±16,6 vs 71,9±17,3) y consumían más alcohol (26,1% vs 0%) y tabaco (67,8% vs 14,3%). El 88,9% se diagnosticaron dentro de las primeras 72h y la mayoría recibió levofloxacino (95,6%). El 85% necesitaron ingreso hospitalario, el 11,7% en UCI y el 4,4% fallecieron. Conclusiones: Coincidiendo con la introducción de la antigenuria, se observa un aumento de incidencia de neumonía por Legionella en nuestra área sanitaria, con tasas en los últimos años que se sitúan entre las más altas de nuestro país. A pesar de tener pacientes con elevada edad media y un alto porcentaje de comorbilidades, la mortalidad fue reducida

Objective: Most of the data on Legionella pneumonia in our country come from the Mediterranean area, and there are few studies from the Northwest area. This study tries to assess the situation of this infection in this area. Method: Retrospective study of all patients with positive Legionella antigenuria treated at the University Hospital Lucus Augusti in Lugo (Spain) from 2001, the year in which this test was introduced in our centre, until 2015. We analysed epidemiological data, risk factors, clinical, radiological and biochemical findings, and clinical outcome. Results: The sampled included 136 patients. When comparing the first five years of the study with the last five, the incidence increased from 10.9 to 64.5 cases/1,000,000; the number of antigenuria requests increased 3.4 times, and compared to other pneumonia aetiologies Legionella increased from 0.9% to 15%. The mean age was 64.1years and 84.6% were males; 74.3% had comorbidities. Males were significantly younger (62.7±16.6 vs 71.9±17.3) and consumed more alcohol (26.1% vs 0%) and tobacco (67.8% vs 14.3%). Diagnosis was established within the first 72hours in 88.9% of cases and most received levofloxacin (95.6%). Hospitalisation was needed in 85% of cases, 11.7% in ICU and 4.4% died. Conclusions: After the introduction of antigenuria there was an increase in the incidence of Legionella pneumonia recorded in our health area. Its rate in recent years has been one of the highest in our country. Despite the fact that the patients had advanced age and comorbidities, mortality was low

Comportamiento de la prueba KAtex en el cribado y diagnóstico de la leishmaniasis visceral en un hospital de referencia / Performance of the KAtex test in screening and diagnosis for visceral leishmaniasis in a reference hospital

Introducción. La utilización de pruebas diagnósticas simples empleando muestras no invasivas en el diagnóstico de la leishmaniasis visceral (LV) en nuestro entorno puede resultar muy útil, siendo necesario compararlas con los métodos tradicionales. El objetivo de este trabajo fue conocer la utilidad diagnóstica de la prueba KAtex en la orina de pacientes con sospecha de LV en nuestro medio. Material y métodos. De forma retrospectiva se revisaron las historias clínicas de los pacientes con sospecha de LV a los que se les realizó la prueba KAtex entre 2009 y 2015. Para la evaluación de su capacidad diagnóstica se seleccionaron los pacientes a los que se les había investigado la presencia del parásito en médula ósea. Resultados. De los 110 pacientes estudiados, en 44 (40%) se realizó biopsia de médula ósea para la investigación de Leishmania. En estos pacientes la sensibilidad de la prueba KAtex fue del 50%, la especificidad del 96,7%, el valor predictivo positivo del 87,5% y el valor predictivo negativo del 80,5%. Conclusiones. La sensibilidad de la antigenuria KAtex es demasiado baja para recomendarla como único método en la detección de LV en nuestro medio (AU)

Introduction. Performing of diagnostic test simple using samples not invasive in the diagnosis of visceral leishmaniasis (VL) may be very beneficial, being necessary comparing to traditional methods. The objective of this study was to know the reliability of test KAtex in the urine of patients with suspicion of VL. Material and methods. Retrospectively were reviewed the medical histories of patients with suspected of VL to which are performed the test between 2009 and 2015. For its analysis were selected the patients to which is them had made study of the parasite in bone marrow. Results. A total of 110 patients were studied, and bone marrow biopsy for research of Leishmania was performed in 44 (40%). In these patients the sensitivity of the test was 50%, the specificity of 96.7%, positive predictive value of 87.5% and negative predictive value of 80.5%. Conclusions. KAtex antigenuria sensitivity is too low recommending it as a unique method in the detection of VL in our medium (AU)

Neumonía por Legionella, ¿cuándo solicitar la antigenuria en orina? / Legionella's pneumonia. When is useful the urinary antigen test?

No disponible

Homogeneous electrochemical detection of hippuric acid in urine based on the osmium-antigen conjugate.

A homogeneous electrochemical immunoassay is based on the interaction of osmium-antigen conjugate with its antibody. The novelty presented herein is the direct conjugation of the osmium complex to a small antigen and the application of the quantitative analysis of the antigen and its antibody as the electrical signal for homogeneous immunoassay. The small antigen chosen is hippuric acid (HA), a major urinary metabolite in toluene-exposed humans. As a redox mediator, [Os(4,4'-dimethoxy-2,2'-bipyridine)2(4-aminomethylpyridine-HA)Cl](+/2+) (Os-HA antigen) has been synthesized and characterized on screen-printed carbon electrodes. The synthesized Os-HA antigen shows reversible redox peaks at E(½)=0.056 V versus Ag/AgCl. The homogeneous competitive immunoassay relies on the interaction between Os-HA antigen conjugate and free antigen to its antibody, which can generate electrical signals linearly proportional to the free antigen monitored by cyclic voltammetry and differential pulse voltammetry in the range of 10 µg mL(-1) to 5.12 mg mL(-1). The cutoff concentration of HA in urine samples is 2.0 mg mL(-1), so the method can be used to develop a HA immunosensor. Moreover, the proposed homogeneous electrochemical immunoassay method can be applied to detect low concentrations of small antigens found in the healthcare area.

Development of an automatic laboratory computer flagging system to identify urine albumin samples potentially affected by antigen excess ('hooking').

BACKGROUND: Immunoassays for urinary albumin are often subject to the problem of antigen excess (the 'hook' effect) at high albumin concentrations. We developed an automated protocol to identify such samples based on urinary albumin to creatinine ratio (uACR) and urinary total protein (uTP) results. METHODS: An automated flagging system was designed and written into the laboratory computer system to alert technical staff to samples potentially affected by the 'hook effect'. This flag was activated when there was a combination of an uTP of ≥2400 mg/L and an uACR of <30 mg/mmol. RESULTS: The potential rate of false-negative uACR results was approximately 0.17% in samples from primary care and diabetic clinic sources. CONCLUSIONS: Samples with falsely low uACR results were identified, allowing the vast majority of results to be authorized without intervention. The protocol prevented the reporting of false-negative uACR results which might impact on the management of patients.

Application of Dolichos biflorus in immunoassay detection of kidney collecting duct biomarkers.

Currently there are no biomarkers for detecting collecting duct damage in man. Antibodies to several collecting duct-specific antigens exist but sandwich assays have been difficult to establish due to the need for two different antibodies to the same protein. We hypothesized that a collecting duct-specific lectin could be used in combination with a collecting duct-specific antibody to negate the need for two different antibodies. The collecting duct specificity of selected antibodies (NiCa II 13C2, Pap XI 3C7, HuPaP VII 2B11 and aquaporin 2), was verified by immunohistochemistry. Aquaporin 2 and Pap XI 3C7 were used successfully in setting up assays with the lectin Dolichos biflorus, using the Meso Scale Discovery (MSD) platform. Antigen expression was highest in the papillae of rat and human kidney (corresponding to the greatest density of collecting ducts) and was also present in normal urine. We propose that further qualification and validation would lead to an assay for detecting collecting duct damage in man.

Evaluation of three Immunochromatographic Assays for Detection of Legionella pneumophila serogroup 1 Antigen in Urine Samples

Los métodos inmunocromatográficos Uni-Gold, SAS y BinaxNOW para la detección cualitativa del antígeno de Legionellapneumophila serogrupo 1 en orina fueron comparadosempleando 39 muestras de orina, sin congelar y sin concentrar,de pacientes con Enfermedad del Legionario. La prueba Uni-Gold detectó el antigen en el 41% de los casos (16/39), SAS enel 61,5% (24/39) y Binax NOW en el 74,3% (29/39). La pruebaBinax NOW mostró los mejores resultados en la detección delantígeno de L. pneumophila serogrupo 1 en muestras de orina(AU)

The Uni-Gold, the SAS and the Binax NOW immunochromatographictest (ICT) urinary antigen assays for the qualitativedetection of Legionella pneumophila serogroup 1 were comparedusing 39 unfrozen and nonconcentrated urine samplesfrom patients with Legionnaires´ disease (LD). The Uni-Gold antigentest detected the urinary antigen in 41% (16/39), the SASantigen test in 61.5% (24/39), and the Binax NOW antigen test in74.3% (29/39). The Binax NOW ICT assay showed the best resultswhen detecting L. pneumophila urinary antigen(AU)

Comparación de cinco ensayos comerciales para la detección de antígenos de Legionella pneumophila en orina / Comparison of five commercial assays for the detection of Legionella pneumophila antigens in urine

Objetivo: la detección de antigenuria es la herramienta fundamental para el diagnóstico de la infección por Legionella. El objetivo es comparar cinco métodos disponibles comercialmente para la detección de antígenos solubles de Legionella pneumophila en orina. Métodos: se han estudiado 71 muestras de orina procedentes de casos de infección por la bacteria (62 muestras) o de casos de infección por virus respiratorio sincitial (9 casos). Las muestras se han analizado para la detección de antígenos solubles de L. pneumophila por métodos inmunoenzimáticos (ELISA) (Binax y Bartels) e inmunocromatográficos (IC) (Binax, SAS y Uni-Gold). Resultados: se ha obtenido resultado idéntico en los cinco análisis en 52 muestras (73,2%) (35 positivas y 17 negativas). Las muestras con resultado discrepante se han clasificado por el criterio de la mayoría de los resultados y/u otros resultados de laboratorio (serología) y/o antecedentes epidemiológicos. Así han sido finalmente clasificadas como positivas 51 muestras, y como negativas, las 20 restantes. Los valores de sensibilidad de ELISA-Binax, ELISA-Bartels, IC-Binax, IC-SAS e IC-Uni-Gold han sido del 80,4, el 100, el 82,4, el 86,3 y el 70,6%, respectivamente. Los valores correspondientes de especificidad han sido del 90, el 95, el 100, el 95 y el 100%. Conclusiones: los resultados indican que los métodos evaluados son adecuados al diagnóstico de la infección por Legionella, con algunas reservas en cuanto a la sensibilidad de alguno de ellos (AU)

Objective: Antigenuria detection is the main approach for diagnosing Legionella infections. The aim of this study was to compare 5 commercially available methods for detecting Legionella pneumophila soluble antigens in urine. Methods: Seventy-one urine samples were tested, 62 from patients with bacterial infection and 9 from patients with respiratory syncytial virus infection. All samples were assayed for the presence of L. pneumophila by immunoenzymatic (ELISA) (Binax and Bartels), and immunochromatographic (IC) (Binax, SAS and Uni-Gold) methods. Results: Identical results (35 positive and 17 negative) were obtained by the 5 assays in 52 samples (73.2%). Samples showing discrepant results were classified by the majority criterion, and/or other laboratory results (serology), and/or epidemiological findings. On this basis, 51 samples were ultimately classified as positive, and 20 as negative. Sensitivity values of ELISA-Binax, ELISA-Bartels, IC-Binax, IC-SAS and IC-Uni-Gold were 80.4, 100, 82.4, 86.3, and 70.6%, respectively. Corresponding values for specificity were 90, 95, 100, 95 and 100%. Conclusions: The results indicate that the methods compared are all adequate for diagnosing Legionella infection, although some have certain limitations regarding sensitivity (AU)

Evaluation of adsorption of urine cystatin C to the polymer materials on the microplate by an antigen capture enzyme-linked immunosorbent assay.

BACKGROUND: Cystatin C is a low molecular weight protein of 13 kDa with an isoelectric point of 9.3. Its adsorption on the urine sampling containers may cause the underestimation of cystatin C levels. We newly developed an antigen capture enzyme-linked immunosorbent assay (ELISA) of sandwich method for measurement of adsorbed level. METHODS: We used a polystyrene microplates with 3 different polymers. These include high hydrophobic, low hydrophobic, and hydrophilic materials. Using the same microplate, the absorbed protein was measured by an antigen Capture ELISA, and calibration was conducted by an ordinary ELISA. RESULTS: In normal urine the concentrations of absorbed cystatin C levels to the 3 materials at day 1 were 0.50, 0.32-0.84 microg/l (median, interquartile range), 0.28, 0.21-0.37 microg/l, and <0.08, <0.08-0.09 microg/l in high hydrophobic, low hydrophobic, and high hydrophilic material, respectively. The absorption rate was 6%, 3%, and 1%, respectively. The adsorption is dependent on urine pH. It changes reciprocally with urine protein concentration. In pathologic urine, the absolute absorption level was <0.08 microg/l on the median, and the adsorption ratio (absorption level/urine level) was much less than 0.5% of that in normal urine. CONCLUSION: In the clinical setting, the absorption of cystatin C to sample containers is negligible since the rate of adsorption is low both in normal and pathologic urine. The material with high hydrophilic surface processing may be used for other proteins when interaction of the proteins with surface material affects the value to clinical decision.

Resin-based micropipette tip for immunochromatographic assays in urine samples.

A novel bioanalysis system based on immunochromatography was developed in connection with a nitrocellulose resin modified micropipette tip, such as ZipTip. The sandwich-type immunoassay was applied to our bioanalysis system. The simple handling of the micropipette enabled us to increase the sample volume and detect low concentrations of target antigens in urine samples. In addition, the washing procedure could also be performed easily to reduce the background signal levels. For analytical evaluations, the color intensity was captured by a flatbed scanner, and processed by a software. We have achieved the detection of human chorionic gonadotropin (hCG) and prostate-specific antigen (PSA). The detection limit of hCG was 0.5 ng/ml (0.05 ng/tip), which is comparable to that of other conventional immunochromatographic systems. Moreover, the detection of PSA was greatly improved over the existing systems with the application of different sample volumes, such as 1 ng/ml (0.2 ng/tip) in a 200 microl sample volume, and 1 ng/ml (0.3 ng/tip) in 300 microl sample volume. Our bioanalysis system is a promising candidate for application to point-of-care tests with its simple handling and high sensitivity.

Detección de antígenos en la orina / Detection of antigens in urine

No disponible

Estudio de un brote de infección por Legionella pneumophila / Legionnaire's disease outbreak

Fundamento y objetivo: Describir un brote comunitario de neumonía por Legionella pneumophila serogrupo 1 ocurrido en la ciudad de Mataró en agosto de 2002, cuyo origen fue una torre de refrigeración. Pacientes y método: Estudio observacional y prospectivo. Se analizan aspectos epidemiológicos, factores de riesgo, hallazgos clínicos, radiológicos y microbiológicos. Resultados: El brote de infección afectó a 151 pacientes: un 62% eran varones y la edad media fue de 58,4 años. Se diagnosticó a 7 de fiebre de Pontiac y a 144 casos de neumonía (un 79% confirmadas, un 14% sospechosas y un 7% probables). Un 40% de los pacientes eran fumadores, un 53,5% tenía alguna enfermedad subyacente y un 22% eran diabéticos. Los síntomas predominantes fueron fiebre (97%), escalofríos y mialgias (ambos en el 63%), cefalea (54%) y tos (53%). La imagen radiológica más frecuente fue la condensación unilobular (71%). La semiología respiratoria fue normal en el 38%. Un 43% de los pacientes tenían criterios clínicos de gravedad. Un 16% se clasificó en los grupos IV-V de Fine. El diagnóstico se efectuó por antigenuria en el 76%; 10 pacientes tenían cultivo de muestras respiratorias positivo. El estudio molecular mostró coincidencia entre las cepas de las muestras clínicas y las de la torre de refrigeración. El tratamiento en el 95,6% de los casos fue con claritromicina. La mortalidad fue del 1,4%. Conclusiones: El brote de infección por L. pneumophila afectó a muchas personas en un período muy breve. La prueba diagnóstica más útil fue la antigenuria. El aislamiento de Legionella en muestras respiratorias fue fundamental para establecer la fuente de la infección. La baja mortalidad está relacionada probablemente con la rapidez del diagnóstico y el tratamiento adecuado

Background and objective: To describe an outbreak of Legionella pneumophila serogroup 1 in Mataró, Catalunya, Spain, in August 2002. The source of the microorganism was a cooling tower. Patients and method: Prospective and observational study with analysis of epidemiological, clinical, and microbiological data. Results: 151 patients were affected (62% male), with a mean age of 58.4 years old. Seven patients were classified as Pontiac Fever and 144 suffered from pneumonia. The diagnosis of pneumonia was confirmed in 79% of cases, was considered suspicious in 14% and probable in 7%. Forty per cent of patients were smokers and 53.5% had comorbidities, mainly diabetes mellitus (22%). Chief symptoms were fever (97%), chills and muscular pain (63% respectively), headache (54%) and cough (53%). Pulmonary condensation was the more frequent radiological feature (71%). Normal pulmonary exploration was observed in 38%. Forty-three per cent of cases were severely ill, and 16% of petients belonged to Fine's IV or V class. Antigenuria was the most important test for diagnosis, which confirmed 76% of cases. Legionella spp. was obtained in respiratory secretions of 10 patients. Molecular analysis confirmed clonality between respiratory microorganisms and that obtained in the cooling tower. Conclusion: The outbreak involved an important number of subjects in a short period of time. Antigenuria was the most useful test. However, the isolation of L. pneumophila from patients permitted the prompt identification of microorganism's source in a cooling tower. The low mortality observed probably relates to a rapid diagnosis and its target treatment

Impacto de las peticiones de detección de antígeno en orina y su porcentaje de positividad en la incidencia de casos esporádicos de neumonía por Legionella en Castellón / No disponible

Fundamentos: En este trabajo se evalúa el impacto que tiene el número de peticiones de análisis y su porcentaje de positividad sobre la endemia de legionelosis registrada de un área de la provincia de Castellón durante el periodo de implantación de la prueba (2001-2003).Métodos: Se excluyeron las peticiones repetidas y los casos asociados a brotes. Se estimó el incremento de casos esporádicos y del porcentaje de positividad mediante el riesgo relativo, tomando como referencia el primer año. Resultados: Hubo 2.068 peticiones correspondientes a1.819 enfermos. El porcentaje de enfermos positivos fue de 2,3%, sin diferencias significativas entre laboratorios o años. El número de casos esporádicos se incrementó en 9,3 veces (2,8-30,7).Conclusiones: El incremento de casos esporádicos registrados aparece como un artefacto. El aumento de peticiones de análisis incrementan el número de casos diagnosticados como efecto de arrastre, de modo que el aspecto pseudoepidémico del periodo tendría un componente de endemia descubierta cuya magnitud se podría estimar a partir de este indicador. Convendría, por otra parte, conocer los criterios de petición en cada hospital y las características de los enfermos con resultados negativos (AU)

Purpose: This work aims to ascertain the impact of the total number of urine antigen tests performed and the percent of positive results on the endemic level of legionellosis registered in an area of Castellón (Spain)during the period of introduction of this analytic method(2001-2003).Methods: Repeated analysis and outbreak associated cases were excluded from laboratory records. The increment of sporadic cases and percent of positive results were calculated by computing the relative risk (RR) with the first year as reference. Results: There were 2068 test performed from 1819patients.. The percent of positive results was 2.3%, without statistical differences between laboratories and years. The increment of endemic level registered resulted in a RR = 9.3 (2.8-30.7).Conclusions: The rise on registered sporadic cases appears as an artefact. The increment of patients with analysis reveal an endemic component of this pseudoepidemic period whose magnitude can be estimated by this indicator. However, clinical criteria of analytical petitions in each setting and characteristics of patients with negative results should be taken into account (AU)

Development of an ELISA test for determination of the urinary trypsin inhibitor: analytical performance and applications.

Increased urinary excretion of urinary trypsin inhibitor (UTI) has been reported in various inflammatory conditions and in Alzheimer's subjects, but its diagnostic potential remains to be elucidated. A reliable and specific enzyme-linked immunosorbent assay (ELISA) test for the determination of the UTI in human urine was developed. This assay was performed using 96-well microtiter plates. The plate surface is coated with an anti-UTI polyclonal antibody, the urine sample was added in a dilution range, and the detection was achieved using the enzyme-conjugated antibody. The assay was quantified by the build-up of colored product upon the addition of the substrate. Recoveries were 93%, and the intra- and inter-assay CVs were 4.25% and 21%, respectively. The ELISA showed parallelism of standard and urine samples and no significant interference by the biological matrix. The usefulness of the assay has been demonstrated by applying it to urine samples from Alzheimer's disease patients, and comparing with negative controls. UTI urinary levels are significantly increased in Alzheimer's subjects.

SURUSS in perspective.

BACKGROUND: Until the publication of the Serum Urine and Ultrasound Screening Study (SURUSS) report, it was difficult to compare the different antenatal screening tests for Down's Syndrome because of variations in study designs. We here present the main results from SURUSS, updated to take account of recent information on nuchal translucency in Down's Syndrome pregnancies, and discuss their implications. METHODS: SURUSS was a prospective study of 47,053 singleton pregnancies (including 101 pregnancies with Down's Syndrome) conducted in 25 maternity units. Nuchal translucency measurements were taken. Serum and urine samples collected between 9 and 13 weeks, and again between 14 and 20 weeks of pregnancy were stored. Samples from each affected pregnancy and five matched controls were tested for currently used or suggested biochemical Down's Syndrome screening markers. Pregnancies were followed up to determine the presence or absence of Down's Syndrome. For an 85% Down's Syndrome detection rate, the false-positive rate for the Integrated test (nuchal translucency and pregnancy associated plasma protein-A [PAPP-A] at 11 completed weeks of pregnancy, and alpha-fetoprotein, unconjugated oestriol [uE(3)], free beta or total human chorionic gondaotrophin (hCG) and inhibin-A in the early second trimester) was 0.9%, the Serum integrated test (without nuchal translucency) 2.7%, the Combined test (nuchal translucency with free beta-hCG and PAPP-A at 11 weeks) 4.3%, the Quadruple test (alpha-fetoprotein, uE(3), free beta or total hCG and inhibin-A) 6.2%, and nuchal translucency at 11 weeks, 15.2%. All tests included maternal age. Using the Integrated test at an 85% detection rate, there would be six diagnostic procedure-related unaffected fetal losses following amniocentesis per 100,000 women screened compared with 35 using the Combined test or 45 with the Quadruple test. CONCLUSIONS: The Integrated test offers the most effective and safe method of screening for women who attend in the first trimester. The next best test is the Serum integrated test. The Quadruple test is the best test for women who first attend in the second trimester. There is no justification for retaining the Double (alpha-fetoprotein and hCG) or Triple (alpha-fetoprotein, uE(3), and hCG) tests, or nuchal translucency alone (with or without maternal age) in antenatal screening for Down's Syndrome.

Hyperglycosylated hCG (invasive trophoblast antigen, ITA) a key antigen for early pregnancy detection.

OBJECTIVES: Hyperglycosylated human chorionic gonadotrophin (hCG) is an hCG variant with extra-large O-linked oligosaccharides, produced by phenotypically invasive cytotrophoblast cells in choriocarcinoma and pregnancy. It is the principal form of hCG produced in the first weeks of gestation. We investigated the importance of hyperglycosylated hCG in pregnancy testing and its detection by current hCG tests. DESIGN AND METHODS: We measured the concentration of hyperglycosylated hCG and total hCG in 512 pregnancies throughout gestation. We assessed and compared the abilities of 14 commonly used commercial laboratory hCG tests and 18 home pregnancy tests to detect regular and hyperglycosylated hCG. RESULTS: Hyperglycosylated hCG is the principal source of hCG-related immunoreactivity in early pregnancy. In the week following missing menses, hyperglycosylated hCG measurements may be more sensitive than regular hCG measurements in detecting pregnancy. Of 14 commercial laboratory hCG tests, 3 appropriately detected hyperglycosylated hCG standard. Of 18 different home pregnancy products 11 poorly or very poorly detected this key antigen. CONCLUSIONS: Hyperglycosylated hCG may be the key molecule in the detection of early pregnancy. However, the majority of tests poorly detected or failed to detect this key antigen. New pregnancy tests are needed that either solely detect hyperglycosylated hCG or equally detect regular hCG and hyperglycosylated hCG.

Clinical graft evolution of lymphocytes, polymorphonuclear cells, and antigen expression in tubular renal cells in the urine sediment of 20 renal allograft recipients.

Urinary samples from 20 kidney transplant recipients were studied to determine the cellular composition of the sediments using an immunocytological (IC) technique. The expression of HLA class I (A, B, C) and class II (DR, DQ, DP), CD2, CD3, CD4, CD8, and interleukin (IL)-2 receptor (IL-2R) on lymphocytes was assessed using a panel of monoclonal antibodies. The results were correlated with graft function and with the number of episodes of acute renal graft rejection (AR) during a period of 6 months posttransplantation. The cellular infiltration of lymphocytes (LC) and polymorphonuclear cells (PMNC) also was studied using a standard cytology (SC) technique. During this period, 17 of 30 episodes of graft dysfunction due to AR occurred in 12 patients: 8 to acute tubular necrosis (ATN) (n = 8); 4 to cyclosporine (CsA) toxicity (n = 4) and 1 to amphotericin toxicity (n = 1). The diagnosis of AR was made clinically by 3 independent observers, using biopsy in some cases. The immunocytology showed a significantly increased expression of HLA-DR, DO, and DP namely, greater than 20% positivity in 10% of samples on the tubular epithelial cells (TEC) of patients presenting with versus without AR (P < or =.001). In addition, a high correlation was observed between the expression of IL-2R and the presence of AR (p < or =.002). The standard cytology results showed a significantly increased percentage of LC and decreased percentage of PMNCs in samples obtained 2 days prior to the clinical manifestations of patients who developed AR (P =.001). A greater level of expression of antigen determinants was observed prior to AR. These results suggest that immunocytology of urinary sediments, which is a noninvasive technique, has enormous clinical potential for the differential diagnosis of AR, ATN, and CsA toxicity. In our study, the use of HLA class IL-specific monoclonal antibodies (Abs) gave a 100% specificity, 95% sensitivity, and 95% predictability. Although our results also indicate a potential value in the increased IL-2R expression, these findings must be confirmed by further studies. Furthermore, the combination of both immunologic and SC techniques in urinary sediments allows early detection of AR and is cost effective and simple features that could be used routinely for follow-up of renal transplant recipients.

Participation of the interstitium in acute immune-complex nephritis: interstitial antigen accumulation, cellular infiltrate, and MHC class II expression.

Bovine serum albumin (BSA) injected into the rabbits induces acute immune complex glomerulonephritis. Since albumin is filtered and reabsorbed in the tubules, we investigated whether tubulointerstitial cells participate in the pathogenesis of this experimental condition. For this purpose, we induced immune-complex nephritis in 45 rabbits with the injection of 125I-BSA and urinary BSA excretion, glomerular and tubulointerstitial BSA accumulation, lymphocyte infiltration, proliferative activity and MHC class II antigens were examined 2, 4-5 and 6-8 days after immunization. Proteinuria developed day 6-8. BSA was found in urine from day 2 (mean +/- SE; 1089 +/- 339 micro g/24 h) and peaked on day 4 after immunization (2249 +/- 1106). BSA content (cpm/g tissue) in tubulointerstitium (TI) and glomeruli were similar at day 2 (457 +/- 45 and 407 +/- 75, respectively), but afterward increased significantly in TI, reaching a peak level on day 5 (1026 +/- 406) while remained unchanged in glomeruli (388 +/- 95). At the same time, preceding the onset of proteinuria, maximal intensity of the lymphocyte infiltration, proliferative activity and MHC class II antigen expression in tubular cells, monocytes/macrophages and interstitial cells were observed. Our study shows that antigen is excreted in the urine and concentrated in TI in association with overexpression of MHC class II molecules and lymphocyte infiltration. These findings occur prior to the development of proteinuria and suggest that the tubulointerstitial cells play a critical role in the pathogenesis of this model.

Ceftriaxone induced immune hemolytic anemia: detection of drug-dependent antibody by ex-vivo antigen in urine.

There have been a few reported cases of immune hemolytic anemia induced by ceftriaxone. We encountered a patient with immune hemolytic anemia that seemed to be stimulated by a degradation product of ceftriaxone. The patient's direct antiglobulin test was positive only for C3d, and no ceftriaxone-dependent antibodies were detectable in the patient's serum. To demonstrate the presence of the ceftriaxone-induced antibodies, an ex-vivo antigen in urine was obtained from the patient. In addition, we prepared a 1 mg/mL suspension solution of ceftriaxone, and group AB serum as a complement source. Using several combinations of the above reactants, the indirect antiglobulin test was performed. Only the indirect antiglobulin test using the patient's serum with the ex-vivo urine antigen was found to be positive. Other combinations were not reactive. To our knowledge, this is the first reported case in Korea, in which the causative antibody appeared to be stimulated solely by a degradation product of ceftriaxone.