External quality control program in infectious diseases screening at laboratories and blood banks in Latin America: an analysis of the past 5 years.

Objective: To evaluate the screening of blood samples for infectious disease markers at laboratories and blood banks in Latin America per the findings of an External Quality Assessment Program (EQAP). Methods: This qualitative analysis used data from the EQAP coordinated by the Fundação Pro Sangue Hemocentro de São Paulo with the support of the Pan American Health Organization to assess the performance of blood screening for infectious diseases from 2014 to 2018 in Latin America. Each participating laboratory or blood bank received an identical blind panel with 24 blood samples with variable reactivity for all the screening parameters. Panels were processed at each participating facility and results were returned to the Fundação Pro Sangue Hemocentro de São Paulo for individual and joint analyses. Two types of discrepant results were potential failures: false positive results (FPRs) and false nonreactive results (FNRRs). Results: A total of 23 136 samples were evaluated. Global rates of FPR, FNRR, and concordant results were 0.3%, 1.0% and 98.7%, respectively. Seven FNRRs were found for HBsAg (1.0%), 12 for syphilis (2.6%), and 21 for Chagas disease (2.9%). No FNRRs were found for the HIV, HCV, and HTLV viruses. The average accuracy of all the laboratories and blood banks participating in the EQAP during the study period was 99.5% (standard deviation, 0.5%). Conclusion: The findings of this qualitative analysis are positive for blood safety in Latin America, with an average accuracy of 99.5% among the participating laboratories and blood banks. This report reflects an important improvement in blood bank serological screening EQAP-PAHO report since the 2003.

External quality control program in infectious diseases screening at laboratories and blood banks in Latin America: an analysis of the past 5 years / Programa de control externo de la calidad en el tamizaje de enfermedades infecciosas en laboratorios y bancos de sangre de América Latina: análisis de los últimos 5 años / Programa externo de controle de qualidade na triagem de doenças infecciosas em laboratórios e bancos de sangue da América Latina: análise dos últimos 5 anos

[ABSTRACT]. Objective. To evaluate the screening of blood samples for infectious disease markers at laboratories and blood banks in Latin America per the findings of an External Quality Assessment Program (EQAP). Methods. This qualitative analysis used data from the EQAP coordinated by the Fundação Pro Sangue Hemocentro de São Paulo with the support of the Pan American Health Organization to assess the performance of blood screening for infectious diseases from 2014 to 2018 in Latin America. Each participating laboratory or blood bank received an identical blind panel with 24 blood samples with variable reactivity for all the screening parameters. Panels were processed at each participating facility and results were returned to the Fundação Pro Sangue Hemocentro de São Paulo for individual and joint analyses. Two types of discrepant results were potential failures: false positive results (FPRs) and false nonreactive results (FNRRs). Results. A total of 23 136 samples were evaluated. Global rates of FPR, FNRR, and concordant results were 0.3%, 1.0% and 98.7%, respectively. Seven FNRRs were found for HBsAg (1.0%), 12 for syphilis (2.6%), and 21 for Chagas disease (2.9%). No FNRRs were found for the HIV, HCV, and HTLV viruses. The average accuracy of all the laboratories and blood banks participating in the EQAP during the study period was 99.5% (standard deviation, 0.5%). Conclusion. The findings of this qualitative analysis are positive for blood safety in Latin America, with an average accuracy of 99.5% among the participating laboratories and blood banks. This report reflects an important improvement in blood bank serological screening EQAP-PAHO report since the 2003.

[RESUMEN]. Objetivo. Evaluar el tamizaje de muestras de sangre en las que se analizan marcadores de enfermedades infecciosas en laboratorios y bancos de sangre de América Latina según los resultados de un programa de evaluación externa de la calidad (EQAP, por su sigla en inglés). Métodos. Este análisis cualitativo utilizó datos del EQAP —coordinado por la Fundação Pro Sangue Hemocentro de São Paulo con el apoyo de la Organización Panamericana de la Salud— para evaluar la eficacia del tamizaje sanguíneo para la detección de enfermedades infecciosas que se realizó entre el 2014 y el 2018 en América Latina. Cada laboratorio o banco de sangre participante recibió un panel idéntico para análisis a ciegas compuesto por 24 muestras de sangre con reactividad variable para todos los parámetros del tamizaje. Los paneles se procesaron en cada establecimiento participante y los resultados se enviaron a la Fundação Pro Sangue Hemocentro de São Paulo donde se realizaron análisis individuales y conjuntos. Había dos tipos de resultados discrepantes que eran posibles fallas del tamizaje: los positivos falsos (PF) y los negativos falsos (NF). Resultados. En total se evaluaron 23 136 muestras. Las tasas generales de PF, NF y resultados concordantes fueron, respectivamente, del 0,3%, 1,0% y 98,7%. Se obtuvieron siete NF en casos de HBsAg (1,0%), 12 en casos de sífilis (2,6%) y 21 en casos de enfermedad de Chagas (2,9%). No se obtuvieron NF en casos de infección por virus del VIH, el VHC o el VLTH. La precisión promedio de todos los laboratorios y bancos de sangre participantes en el EQAP durante el periodo de estudio fue del 99,5% (desviación típica: 0,5%). Conclusión. Los resultados de este análisis cualitativo son positivos en lo referente a la seguridad sanguínea en América Latina, con una precisión promedio del 99,5% entre los laboratorios y bancos de sangre participantes. Este informe refleja la considerable mejora del tamizaje serológico que se realiza en los bancos de sangre, en comparación con los resultados del informe del EQAP que contó con el apoyo de la OPS y se publicó en el 2003.

[RESUMO]. Objetivo. Avaliar a triagem de marcadores de doenças infecciosas em amostras de sangue realizada em laboratórios e bancos de sangue da América Latina de acordo com os resultados de um Programa Externo de Avaliação de Qualidade (EQAP, na sigla em inglês). Métodos. Esta análise qualitativa usou dados do EQAP coordenado pela Fundação Pró-Sangue Hemocentro de São Paulo, com o apoio da Organização Pan-Americana da Saúde, para avaliar o desempenho da triagem de sangue quanto a doenças infecciosas no período de 2014 a 2018 na América Latina. Cada laboratório ou banco de sangue participante recebeu um painel cego idêntico com 24 amostras de sangue de reatividade variável para todos os parâmetros de triagem. Os painéis foram processados em cada estabelecimento participante e os resultados foram devolvidos à Fundação Pró-Sangue Hemocentro de São Paulo para análises individuais e conjuntas. Dois tipos de resultados discrepantes representavam falhas em potencial: resultados falso-positivos e resultados falso-negativos (não reativos). Resultados. Foram avaliadas 23.136 amostras. As taxas globais de resultados falso-positivos, falso-negativos e concordantes foram de 0,3%, 1,0% e 98,7%, respectivamente. Foram encontrados sete resultados falso-negativos para HBsAg (1,0%), 12 para sífilis (2,6%) e 21 para doença de Chagas (2,9%). Não houve resultados falso-negativos para os vírus HIV, HCV e HTLV. A acurácia média de todos os laboratórios e bancos de sangue que participaram do EQAP durante o período do estudo foi de 99,5% (desvio padrão de 0,5%). Conclusões. Os resultados desta análise qualitativa são positivos para a segurança do sangue na América Latina, com uma acurácia média de 99,5% entre os laboratórios e bancos de sangue participantes. Este rela- tório reflete uma melhoria importante na triagem sorológica dos bancos de sangue em relação aos resultados do relatório do EQAP apoiado pela OPAS que foi publicado em 2003.

External quality control program in infectious diseases screening at laboratories and blood banks in Latin America: an analysis of the past 5 years / Programa de control externo de la calidad en el tamizaje de enfermedades infecciosas en laboratorios y bancos de sangre de América Latina: análisis de los últimos 5 años / Programa externo de controle de qualidade na triagem de doenças infecciosas em laboratórios e bancos de sangue da América Latina: análise dos últimos 5 anos

ABSTRACT Objective. To evaluate the screening of blood samples for infectious disease markers at laboratories and blood banks in Latin America per the findings of an External Quality Assessment Program (EQAP). Methods. This qualitative analysis used data from the EQAP coordinated by the Fundação Pro Sangue Hemocentro de São Paulo with the support of the Pan American Health Organization to assess the performance of blood screening for infectious diseases from 2014 to 2018 in Latin America. Each participating laboratory or blood bank received an identical blind panel with 24 blood samples with variable reactivity for all the screening parameters. Panels were processed at each participating facility and results were returned to the Fundação Pro Sangue Hemocentro de São Paulo for individual and joint analyses. Two types of discrepant results were potential failures: false positive results (FPRs) and false nonreactive results (FNRRs). Results. A total of 23 136 samples were evaluated. Global rates of FPR, FNRR, and concordant results were 0.3%, 1.0% and 98.7%, respectively. Seven FNRRs were found for HBsAg (1.0%), 12 for syphilis (2.6%), and 21 for Chagas disease (2.9%). No FNRRs were found for the HIV, HCV, and HTLV viruses. The average accuracy of all the laboratories and blood banks participating in the EQAP during the study period was 99.5% (standard deviation, 0.5%). Conclusion. The findings of this qualitative analysis are positive for blood safety in Latin America, with an average accuracy of 99.5% among the participating laboratories and blood banks. This report reflects an important improvement in blood bank serological screening EQAP-PAHO report since the 2003.

RESUMEN Objetivo. Evaluar el tamizaje de muestras de sangre en las que se analizan marcadores de enfermedades infecciosas en laboratorios y bancos de sangre de América Latina según los resultados de un programa de evaluación externa de la calidad (EQAP, por su sigla en inglés). Métodos. Este análisis cualitativo utilizó datos del EQAP —coordinado por la Fundação Pro Sangue Hemocentro de São Paulo con el apoyo de la Organización Panamericana de la Salud— para evaluar la eficacia del tamizaje sanguíneo para la detección de enfermedades infecciosas que se realizó entre el 2014 y el 2018 en América Latina. Cada laboratorio o banco de sangre participante recibió un panel idéntico para análisis a ciegas compuesto por 24 muestras de sangre con reactividad variable para todos los parámetros del tamizaje. Los paneles se procesaron en cada establecimiento participante y los resultados se enviaron a la Fundação Pro Sangue Hemocentro de São Paulo donde se realizaron análisis individuales y conjuntos. Había dos tipos de resultados discrepantes que eran posibles fallas del tamizaje: los positivos falsos (PF) y los negativos falsos (NF). Resultados. En total se evaluaron 23 136 muestras. Las tasas generales de PF, NF y resultados concordantes fueron, respectivamente, del 0,3%, 1,0% y 98,7%. Se obtuvieron siete NF en casos de HBsAg (1,0%), 12 en casos de sífilis (2,6%) y 21 en casos de enfermedad de Chagas (2,9%). No se obtuvieron NF en casos de infección por virus del VIH, el VHC o el VLTH. La precisión promedio de todos los laboratorios y bancos de sangre participantes en el EQAP durante el periodo de estudio fue del 99,5% (desviación típica: 0,5%). Conclusión. Los resultados de este análisis cualitativo son positivos en lo referente a la seguridad sanguínea en América Latina, con una precisión promedio del 99,5% entre los laboratorios y bancos de sangre participantes. Este informe refleja la considerable mejora del tamizaje serológico que se realiza en los bancos de sangre, en comparación con los resultados del informe del EQAP que contó con el apoyo de la OPS y se publicó en el 2003.

RESUMO Objetivo. Avaliar a triagem de marcadores de doenças infecciosas em amostras de sangue realizada em laboratórios e bancos de sangue da América Latina de acordo com os resultados de um Programa Externo de Avaliação de Qualidade (EQAP, na sigla em inglês). Métodos. Esta análise qualitativa usou dados do EQAP coordenado pela Fundação Pró-Sangue Hemocentro de São Paulo, com o apoio da Organização Pan-Americana da Saúde, para avaliar o desempenho da triagem de sangue quanto a doenças infecciosas no período de 2014 a 2018 na América Latina. Cada laboratório ou banco de sangue participante recebeu um painel cego idêntico com 24 amostras de sangue de reatividade variável para todos os parâmetros de triagem. Os painéis foram processados em cada estabelecimento participante e os resultados foram devolvidos à Fundação Pró-Sangue Hemocentro de São Paulo para análises individuais e conjuntas. Dois tipos de resultados discrepantes representavam falhas em potencial: resultados falso-positivos e resultados falso-negativos (não reativos). Resultados. Foram avaliadas 23.136 amostras. As taxas globais de resultados falso-positivos, falso-negativos e concordantes foram de 0,3%, 1,0% e 98,7%, respectivamente. Foram encontrados sete resultados falso-negativos para HBsAg (1,0%), 12 para sífilis (2,6%) e 21 para doença de Chagas (2,9%). Não houve resultados falso-negativos para os vírus HIV, HCV e HTLV. A acurácia média de todos os laboratórios e bancos de sangue que participaram do EQAP durante o período do estudo foi de 99,5% (desvio padrão de 0,5%). Conclusões. Os resultados desta análise qualitativa são positivos para a segurança do sangue na América Latina, com uma acurácia média de 99,5% entre os laboratórios e bancos de sangue participantes. Este relatório reflete uma melhoria importante na triagem sorológica dos bancos de sangue em relação aos resultados do relatório do EQAP apoiado pela OPAS que foi publicado em 2003.

Comorbidities of Patients With Idiopathic Pulmonary Fibrosis in Four Latin American Countries. Are There Differences by Country and Altitude?

Background: Comorbidities in idiopathic pulmonary fibrosis (IPF) affect quality of life, symptoms, disease progression and survival. It is unknown what are the comorbidities in patients with IPF in Latin America (LA) and if there are differences between countries. Our objective was to compare IPF comorbidities in four countries and analyze possible differences by altitude. Methods: Patients with IPF according 2012 ATS/ERS/JRS/ALAT guidelines, from two cities with an altitude of ≥2,250 m: Mexico City (Mexico) and Bogotá (Colombia) and from three at sea level: Buenos Aires (Argentina) and Lima and Trujillo (Peru). Comorbidities and pulmonary function tests were taken from clinical records. Possible pulmonary hypertension (PH) was defined by findings in the transthoracic echocardiogram of systolic pulmonary arterial pressure (sPAP) >36 mmHg or indirect signs of PH in the absence of other causes of PH. Emphysema as the concomitant finding of IPF criteria on chest tomography plus emphysema in the upper lobes. ANOVA or Kruskal Wallis and χ2-tests were used for comparison. Results: Two hundred and seventy-six patients were included, 50 from Argentina, 86 from Colombia, 91 from Mexico and 49 from Peru. There prevalence of PH was higher in Colombia and Mexico (p < 0.001), systemic arterial hypertension in Argentina (p < 0.015), gastro-esophageal reflux and dyslipidemia in Colombia and Argentina (p < 0.001) and diabetes mellitus in Mexico (p < 0.007). Other comorbidities were obesity (28.4%), coronary artery disease (15.2%) and emphysema (14.9%), with no differences between countries. There was more PH in the altitude cities than those at sea level (51.7 vs. 15.3%, p < 0.001). In patients from Bogotá and Mexico City, arterial oxygen pressure, saturation (p < 0.001) and carbon monoxide diffusing capacity (p = 0.004) were significantly lower than in cities at sea level. Conclusions: In this study with a significant number of patients, we were able to describe and compare the comorbidities of IPF in four LA countries, which contributes to the epidemiological data of this disease in the region. The main results were the differences in comorbidities between the countries and more PH in the subjects residing in the cities of higher altitude, a finding that should be validated in future studies.

Proptosis ocular como una manifestación de la granulomatosis con poliangeítis (Wegener): Reporte de un caso y revisión de la literatura / Ocular proptosis as a manifestation of Wegener's granulomatosis: A case report

RESUMEN La granulomatosis con poliangeítis (Wegener) es considerada como una enfermedad granulomatosa sistémica, no infecciosa, caracterizada histológicamente por una vasculitis necrosante de pequeño vaso. El tracto respiratorio superior e inferior son los más frecuentemente afectados, en asociación a manifestaciones renales. Sin embargo, también se describe el compromiso aislado de un solo órgano, como es el caso del globo ocular y la órbita. Presentamos el caso de una mujer cuya principal manifestación consistió en un proceso inflamatorio de tejido periorbitario y proptosis del globo ocular izquierdo. La paciente fue valorada en manejo conjunto con el servicio de plástica ocular, otorrinolaringología y finalmente se derivó a reumatología para inicio de terapia inmunosupresora. Se realizó una revisión de la literatura, en búsqueda de reportes de caso y series de caso que permitieran comparar las presentaciones clínicas y desenlaces más frecuentes.

A B S T R A C T Granulomatosis with polyangiitis (Wegener) is considered as a systemic, non-infectious granulomatous disease, histologically noted for its small vessel necrotising vasculitis. The upper and lower respiratory tracts are the most frequently affected, in association with renal manifestations. However, the isolated involvement of a single organ, such as the eyeball and the orbit is also described. The case is presented of a woman whose main manifestation was an inflammatory process of periorbital tissue and proptosis of the left eyeball. The patient was evaluated jointly with eye plastic surgery, and the ear, nose and throat, and rheumatology departments. A literature review was carried out, looking for case reports and case series that allowed comparisons to made between the clinical manifestations and the most frequent outcomes.

Comparative evaluation of immunoassays to improve access to diagnosis for Chagas disease in Colombia.

OBJECTIVE: Chagas disease affects over six million people, but less than 1% are diagnosed and treated. Complicated diagnostic processes are a major barrier. Colombia's previous diagnostic algorithm, using in-house tests, was difficult to scale up, creating significant access barriers for patients. A new algorithm using commercially manufactured immunoassays would potentially improve access, but these tests' performance in Colombian patients with Chagas disease is not well known. METHODS: We assessed seven commercially available assays. Samples (n=501), 93.8% originating from Colombia, were characterized as positive or negative based on standard procedure at the National Reference Laboratory. Performance characteristics were calculated for individual assays and hypothetical test pairings, then compared to the existing algorithm. RESULTS: Five of seven assays exhibited sensitivity >98% while six showed specificity >97%. A total antigen ELISA paired with a recombinant assay provided similar performance to the current diagnostic process. Six of six assays tested proved capable of detecting different Trypanosoma cruzi genetic lineages. CONCLUSIONS: The study indicated that several commercial assays accurately detect T. cruzi infection in Colombian patients. A simplified testing process with two commercial assays could perform comparably to the previous process, reducing cost and accessibility barriers and facilitating national scale-up.

Detección de anticuerpos para Trypanosoma cruzi en donantes de sangre. Caquetá, Colombia, 1995 a 2010 / Detection of Trypanosoma cruzi antibodies in blood donors from Caquetá-Colombia, 1995-2010

RESUMEN Objetivo Caracterizar epidemiológicamente los casos reactivos y confirmados para Trypanosoma cruzi en donantes de sangre del departamento de Caquetá desde 1995 a 2010. Materiales y Métodos Estudio descriptivo, retrospectivo. La información fue obtenida en el banco de sangre y Laboratorio Departamental de Salud Pública de Caquetá, los datos se colectaron en un formulario estandarizado diseñado en Microsoft Excel® con variables específicas, posteriormente se depuró, corroboró y completó la información con las bases de datos nacionales (Registraduría Nacional de Colombia y Base de Datos Única de Afiliados del Fondo de Solidaridad y Garantía (FOSYGA) del sistema de salud colombiano. En el análisis se utilizó estadística descriptiva uni y bivariada en Microsoft Excel® y un análisis de correspondencia múltiple (ACM) con el programador matemático R® versión 3.0. Resultados De 42 516 donaciones tamizadas, se detectaron 261 casos reactivos, 92 resultaron positivos para T. cruzi, 12 negativos y 157 casos sin dato de confirmación. Se consultó la posible ubicación caso a caso con las bases de datos nacionales, estableciendo factibles migraciones a diferentes zonas del país. Conclusión La caracterización y ubicación actual por medio del contraste y búsqueda de información con bases de datos nacionales de los casos positivos confirmados para T. cruzi es un avance importante en salud pública, pues es la primeria línea de información existente en Colombia que entrega gran cantidad de datos caso a caso, con el fin que las autoridades competentes inicien búsqueda activa para el manejo clínico pertinente.(AU)

ABSTRACT Objective The aim of this article is an epidemiology characterize of screening positive samples and confirmed cases to Trypanosoma cruzi in blood donor at Caquetá, Colombia from 1995 to 2010. Material and methods This study was a descriptive and retrospective analysis where the information was obtained from blood bank and Public Health Departmental Laboratory of Caquetá. These were collected on standardized form in Microsoft Excel® with specific variables. Afterward, they were organized and information was added from Colombian data bases as FOSYGA and Registraduría Nacional. Both, multiple correspondence analysis and univariate and bivariate descriptive statistics were used to analyse the data on mathematic program R® and Microsoft Excel®, respectively. Results From a total of 42.516 blood donations, 261 were seropositive and 92 were confirmed cases to T. cruzi. Conclusion: Characterize the confirmed cases of T. cruzi and identify their current location through the looking for the information and its comparation with the national data bases is an important sources to find these confirmed cases in order to give a relevant clinical procedure by the competent authorities.(AU)

Supervivencia de receptores de trasplante renal en Colombia, 2008-2012 / Survival in renal transplant recipients in Colombia, 2008-2012

Resumen Introducción. La Red Nacional de Donación y Trasplantes del Instituto Nacional de Salud reportó que durante 2014 se realizaron en Colombia 1.059 trasplantes de órganos, de los cuales 761 fueron de riñón y, de estos, 643 (84,5 %) correspondieron a órganos provenientes de cadáveres. Objetivo. Describir las características sociodemográficas de los pacientes con trasplante renal y los resultados en términos de supervivencia. Materiales y métodos. Se hizo un estudio observacional y retrospectivo de cohorte mediante el análisis de la base nacional de datos de receptores de trasplante renal. Se estimó la supervivencia global con el método de Kaplan-Meier, se compararon las curvas según sexo, edad, tipo de donante, tipo de régimen de afiliación al sistema de salud y tiempo en lista de espera mediante la prueba de hipótesis de Mantel-Cox (log rank) y una regresión de Cox. Resultados. De los 3.980 pacientes incluidos en el estudio, 338 fallecieron según el Registro Único de Afiliados. Con una mediana de seguimiento de 49 meses, la supervivencia global fue de 6,35 años (IC95% 6,30-6,40), la supervivencia al año del trasplante fue de 97,2 %, a los tres años, de 93,2 %, y a los cinco años, de 90,8 %. La supervivencia fue mayor en los pacientes menores de 50 años receptores de trasplante con donante vivo y con menos de seis meses en lista de espera. Conclusiones. Los resultados reflejaron el panorama de los pacientes con trasplante renal en el país en términos de supervivencia, lo cual sirve de base para estudios prospectivos con seguimiento estricto.

Abstract Introduction: The Red Nacional de Donación y Trasplantes of the Colombian Instituto Nacional de Salud reported that in 2014, 1,059 organ transplants were performed, of which 761 were kidney transplants, and 643 (84.5%) of these were from cadaveric organ donors. Objective: To describe the socio-demographic characteristics of patients who received renal transplants, as well as their outcomes in terms of survival. Materials and methods: National kidney transplants were analyzed through an observational retrospective cohort study. Overall survival was estimated using the Kaplan-Meier method. The survival curves by sex, age, type of donor, type of insurance, and time on the waiting list were compared utilizing the log rank hypothesis and a Cox regression. Results: A total of 3,980 patients were included, of whom 338 died according to the Registry of Affiliates. The median follow-up time was 49 months, overall survival was 6.35 years (95% CI: 6.30 to 6.40), the one-year survival following transplantation was 97.2%, the three-year survival, 93.2%, and the five-year survival, 90.8%. The survival rate was higher in patients under 50 years of age, receptors of living donor transplants, and with less than six months on the waiting list. Conclusions: The results obtained serve as the basis for future studies with strict monitoring of survival among kidney transplant recipients in Colombia.

Determinación del polimorfismo de HLA-A, -B y -DRB1 en donantes de órganos con muerte encefálica representativos de la población general colombiana, 2007-2014 / Determination of HLA-A, -B and -DRB1 polymorphism in brain dead organ donors representative of the Colombian general population, 2007-2014

Resumen Introducción. Los genes que codifican para el sistema de antígenos leucocitarios humanos (Human Leukocyte Antigen, HLA) son muy polimorfos y de gran importancia en procedimientos de trasplante de órganos, ya que la determinación de las frecuencias alélicas en poblaciones específicas se tiene en cuenta entre los criterios científicos para la asignación de órganos. Objetivo. Establecer las frecuencias antigénicas y haplotípicas de HLA-A, -B y -DRB1 en donantes de órganos con muerte encefálica, representativos de la población colombiana. Materiales y métodos. En este estudio descriptivo retrospectivo de 2.506 donantes cadavéricos de órganos, se hizo un análisis alélico y de haplotipos de HLA-A, -B y -DRB1, y se determinó el equilibrio de Hardy-Weinberg. Resultados. Se encontraron 21, 43 y 15 grupos alélicos para los loci A*, B* y DRB1*, respectivamente. Se detectaron 1.268 haplotipos HLA-A, -B y -DR, 409 haplotipos HLA A-B, 383 haplotipos HLA-B-DR y 218 haplotipos HLA-A-DR. Los tres loci se encontraban en equilibrio de Hardy-Weinberg entre el número de heterocigóticos observados y el esperado, con valores de p<0,05. Conclusiones. En este estudio se proporciona información sobre la distribución de los alelos HLA de clase I y II en la población de donantes de órganos provenientes de las seis regionales en las que está dividido el país para la prestación de servicios de trasplante.

Abstract Introduction: Genes encoding for human leukocyte antigens (HLA) are highly polymorphic and of great importance in organ transplantation procedures, as determining allelic frequencies in defined populations is taken into account among the scientific criteria for organ allocation. Objective: The objective of this study was to establish the antigen HLA-A, -B, and -DRB1 haplotype frequencies in organ donors representative of the Colombian population after brain death. Materials and methods: We conducted a descriptive retrospective study involving 2,506 cadaveric organ donors including an allelic and haplotype analysis of HLA-A, -B and -DRB1; we also determined the Hardy-Weinberg equilibrium. Results: We identified 21, 43 and 15 allelic loci for groups A*, B* and DRB1*, respectively. We detected 1,268 HLA-A, -B and -DR, 409 HLA-A-B, 383 HLA-DR-B, and 218 HLA-A-DR haplotypes. The three loci were found to be in Hardy-Weinberg equilibrium between the number of heterozygotes observed and the expected number, with p values of <0.05. Conclusions: This study provides information on the allelic distribution of HLA class I and II in organ donors from the six regions in which Colombia is structurally divided to provide transplant services.

[Survival in renal transplant recipients in Colombia, 2008-2012].

INTRODUCTION: The Red Nacional de Donación y Trasplantes of the Colombian Instituto Nacional de Salud reported that in 2014, 1,059 organ transplants were performed, of which 761 were kidney transplants, and 643 (84.5%) of these were from cadaveric organ donors. OBJECTIVE: To describe the socio-demographic characteristics of patients who received renal transplants, as well as their outcomes in terms of survival. MATERIALS AND METHODS: National kidney transplants were analyzed through an observational retrospective cohort study. Overall survival was estimated using the Kaplan-Meier method. The survival curves by sex, age, type of donor, type of insurance, and time on the waiting list were compared utilizing the log rank hypothesis and a Cox regression. RESULTS: A total of 3,980 patients were included, of whom 338 died according to the Registry of Affiliates. The median follow-up time was 49 months, overall survival was 6.35 years (95% CI: 6.30 to 6.40), the one-year survival following transplantation was 97.2%, the three-year survival, 93.2%, and the five-year survival, 90.8%. The survival rate was higher in patients under 50 years of age, receptors of living donor transplants, and with less than six months on the waiting list. CONCLUSIONS: The results obtained serve as the basis for future studies with strict monitoring of survival among kidney transplant recipients in Colombia.

[Determination of HLA-A, -B and -DRB1 polymorphism in brain dead organ donors representative of the Colombian general population, 2007-2014].

INTRODUCTION: Genes encoding for human leukocyte antigens (HLA) are highly polymorphic and of great importance in organ transplantation procedures, as determining allelic frequencies in defined populations is taken into account among the scientific criteria for organ allocation. OBJECTIVE: The objective of this study was to establish the antigen HLA-A, -B, and -DRB1 haplotype frequencies in organ donors representative of the Colombian population after brain death. MATERIALS AND METHODS: We conducted a descriptive retrospective study involving 2,506 cadaveric organ donors including an allelic and haplotype analysis of HLA-A, -B and -DRB1; we also determined the Hardy-Weinberg equilibrium. RESULTS: We identified 21, 43 and 15 allelic loci for groups A*, B* and DRB1*, respectively. We detected 1,268 HLA-A, -B and -DR, 409 HLA-A-B, 383 HLA-DR-B, and 218 HLA-A-DR haplotypes. The three loci were found to be in Hardy-Weinberg equilibrium between the number of heterozygotes observed and the expected number, with p values of ;0.05. CONCLUSIONS: This study provides information on the allelic distribution of HLA class I and II in organ donors from the six regions in which Colombia is structurally divided to provide transplant services.

Estimation of personal exposure to asbestos of brake repair workers.

Exposure assessments are key tools to conduct epidemiological studies. Since 2010, 28 riveters from 18 brake repair shops with different characteristics and workloads were sampled for asbestos exposure in Bogotá, Colombia. Short-term personal samples collected during manipulation activities of brake products, and personal samples collected during non-manipulation activities were used to calculate 103 8-h TWA PCM-equivalent personal asbestos concentrations. The aims of this study are to identify exposure determinant variables associated with the 8-h TWA personal asbestos concentrations among brake mechanics, and propose different models to estimate potential asbestos exposure of brake mechanics in an 8-h work-shift. Longitudinal-based multivariate linear regression models were used to determine the association between personal asbestos concentrations in a work-shift with different variables related to work tasks and workload of the mechanics, and some characteristics of the shops. Monte Carlo simulations were used to estimate the 8-h TWA PCM-Eq personal asbestos concentration in work-shifts that had manipulations of brake products or cleaning activities of the manipulation area, using the results of the sampling campaigns. The simulations proposed could be applied for both current and retrospective studies to determine personal asbestos exposures of brake mechanics, without the need of sampling campaigns or historical data of air asbestos concentrations.

[Detection of Trypanosoma cruzi antibodies in blood donors from Caquetá-Colombia, 1995-2010]. / Detección de anticuerpos para Trypanosoma cruzi en donantes de sangre. Caquetá, Colombia, 1995 a 2010.

OBJECTIVE: The aim of this article is an epidemiology characterize of screening positive samples and confirmed cases to Trypanosoma cruzi in blood donor at Caquetá, Colombia from 1995 to 2010. MATERIAL AND METHODS: This study was a descriptive and retrospective analysis where the information was obtained from blood bank and Public Health Departmental Laboratory of Caquetá. These were collected on standardized form in Microsoft Excel® with specific variables. Afterward, they were organized and information was added from Colombian data bases as FOSYGA and Registraduría Nacional. Both, multiple correspondence analysis and univariate and bivariate descriptive statistics were used to analyse the data on mathematic program R® and Microsoft Excel®, respectively. RESULTS: From a total of 42.516 blood donations, 261 were seropositive and 92 were confirmed cases to T. cruzi. CONCLUSION: Characterize the confirmed cases of T. cruzi and identify their current location through the looking for the information and its comparation with the national data bases is an important sources to find these confirmed cases in order to give a relevant clinical procedure by the competent authorities.

OBJETIVO: Caracterizar epidemiológicamente los casos reactivos y confirmados para Trypanosoma cruzi en donantes de sangre del departamento de Caquetá desde 1995 a 2010. MATERIALES Y MÉTODOS: Estudio descriptivo, retrospectivo. La información fue obtenida en el banco de sangre y Laboratorio Departamental de Salud Pública de Caquetá, los datos se colectaron en un formulario estandarizado diseñado en Microsoft Excel® con variables específicas, posteriormente se depuró, corroboró y completó la información con las bases de datos nacionales (Registraduría Nacional de Colombia y Base de Datos Única de Afiliados del Fondo de Solidaridad y Garantía (FOSYGA) del sistema de salud colombiano. En el análisis se utilizó estadística descriptiva uni y bivariada en Microsoft Excel® y un análisis de correspondencia múltiple (ACM) con el programador matemático R® versión 3.0. RESULTADOS: De 42 516 donaciones tamizadas, se detectaron 261 casos reactivos, 92 resultaron positivos para T. cruzi, 12 negativos y 157 casos sin dato de confirmación. Se consultó la posible ubicación caso a caso con las bases de datos nacionales, estableciendo factibles migraciones a diferentes zonas del país. CONCLUSIÓN: La caracterización y ubicación actual por medio del contraste y búsqueda de información con bases de datos nacionales de los casos positivos confirmados para T. cruzi es un avance importante en salud pública, pues es la primeria línea de información existente en Colombia que entrega gran cantidad de datos caso a caso, con el fin que las autoridades competentes inicien búsqueda activa para el manejo clínico pertinente.

Factors Associated With Non-compliance of Asbestos Occupational Standards in Brake Repair Workers.

Asbestos and non-asbestos containing brake products are currently used in low- and middle-income countries like Colombia. Because brake products are distributed detached from their supports, they require manipulation before installation, which release fibers and expose workers. Previous studies of our research group have documented exposures in excess of the widely accepted 0.1 f/cm(3) exposure guideline. The aim of this study is to identify factors associated with non-compliance of the 8-h time weighted average (TWA) 0.1 f/cm(3) asbestos occupational limit among brake mechanics (i.e. riveters). Eighteen brake repair shops (BRS) located in Bogotá (Colombia) were sampled during 3 to 6 consecutive days for the entire work-shift. Personal and short-term personal samples were collected following NIOSH methods 7400 and 7402. Longitudinal based logistic regression models were used to determine the association between the odds of exceeding the 8-h TWA 0.1 f/cm(3) asbestos occupational limit and variables such as type of tasks performed by workers, workload (number of products manipulated daily), years of experience as riveters, and shop characteristics. These models can be used to estimate the odds of being currently or historically overexposed when sampling data do not exist. Since the information required to run the models can vary for both retrospective and current asbestos occupational exposure studies, three models were constructed with different information requirements. The first model evaluated the association between the odds of non-compliance with variables related to the workload, the second model evaluated the association between the odds of non-compliance with variables related to the manipulation tasks, and the third model evaluated the association between the odds of non-compliance with variables related with both the type of tasks performed by workers and the workload. Variables associated with the odds of non-compliance included conducting at least one manipulation activity with beveling and grinding of asbestos and non-asbestos containing brake products during the work shift, the location of the worker in the shop during non-manipulation activities, cleaning activities of the manipulation area, the years of experience working as riveters, and the number of asbestos and non-asbestos containing brake products manipulated daily. These models could be useful for current and retrospective occupational studies, in determining the odds of non-compliance of the asbestos occupational limit among brake mechanics.

Personal exposure to asbestos and respiratory health of heavy vehicle brake mechanics.

Asbestos brake linings and blocks are currently used in heavy vehicle brake repair shops (BRSs) in Bogotá, Colombia. Some brake products are sold detached from their supports and without holes, requiring manipulation before installation. The aim of this study was to assess asbestos exposures and conduct a preliminary evaluation of respiratory health in workers of heavy vehicles in BRSs. To estimate asbestos exposures, personal and area samples were collected in two heavy vehicle BRSs. Each shop was sampled during six consecutive days for the entire work shift. Personal samples were collected on 10 workers including riveters, brake mechanics, and administrative staff. Among workers sampled, riveters had the highest phase contrast microscopy equivalent (PCME) asbestos concentrations, with 8-h time-weighted average (TWA) personal exposures ranging between 0.003 and 0.157 f/cm(3). Respiratory health evaluations were performed on the 10 workers sampled. Three workers (30%) had circumscribed pleural thickening (pleural plaques), with calcifications in two of them. This finding is strongly suggestive of asbestos exposure. The results of this study provide preliminary evidence that workers in heavy vehicle BRSs could be at excessive risk of developing asbestos-related diseases.

Perfiles serológicos de hepatitis B en donantes de sangre con anti-HBc reactivos / Serological profiles of hepatitis-B HBcAb-positive blood donors

Objetivo Determinar los perfiles serológicos para el virus de hepatitis B, en donantes de sangre anti-HBc reactivo y antígeno de superficie no reactivo, provenientes de cuatro ciudades del país Métodos Se realizó un estudio prospectivo transversal, durante un período de 17 meses, aplicando el perfil serológico completo de la hepatitis B, en muestras de donantes con anti-HBc reactivo y antígeno de superficie de hepatitis B no reactivo. Los resultados fueron analizados utilizando Microsoft® Excel y Epiinfo V 3.5.1. Resultados Se encontró que el 75 % de los donantes reactivos para anti-HBc en los bancos de sangre, presentaban algún marcador adicional de exposición para el VHB; el 1,3 % de los donantes presentaban marcadores serológicos de infección crónica por hepatitis B y un caso que resultó reactivo solamente para antígeno de superficie de hepatitis B. Se halló perfil de vacunación en el 6,1 % de donantes, que fueron reactivos solamente para anticuerpo contra antígeno de superficie.Conclusiones. Se ratifica la importancia de la tamización de anti-HBc, a los donantes de sangre...(AU)

To assess the serological profiles for HBV in blood donors that were anti-HBc reactive and non-reactive to HBsAg in four Colombian cities. Materials and Methods A prospective transversal study was conducted during 17 months, applying a complete serological profile for HBV in samples from blood donors that were anti-HBc reactive and non-reactive to HBsAg, results were analyzed employing descriptive statistics using Microsoft Excel and Epiinfo V. 3.5.1. Results From donors reactive to anti-HBc, 75.0 % shown some additional infection marker for HBV. 1.3 % of blood donors had serological markers for chronical infection with hepatitis B, and a case had reactivity only for hepatitis B surface antigen (HBsAg). 6.1 % of donors showed a vaccination serological profile, only with reactivity to anti-HBsAg antibodies. Conclusions With this study, anti-HBc blood screening importance was confirmed...(AU)

[Serological Profiles of Hepatitis-B HBcAb-Positive Blood donors ]. / Perfiles serológicos de hepatitis B en donantes de sangre con anti-HBc reactivos.

OBJECTIVE: To assess the serological profiles for HBV in blood donors that were anti-HBc reactive and non-reactive to HBsAg in four Colombian cities. MATERIALS AND METHODS: A prospective transversal study was conducted during 17 months, applying a complete serological profile for HBV in samples from blood donors that were anti-HBc reactive and non-reactive to HBsAg, results were analyzed employing descriptive statistics using Microsoft Excel and Epiinfo V. 3.5.1. RESULTS: From donors reactive to anti-HBc, 75.0 % shown some additional infection marker for HBV. 1.3 % of blood donors had serological markers for chronical infection with hepatitis B, and a case had reactivity only for hepatitis B surface antigen (HBsAg). 6.1 % of donors showed a vaccination serological profile, only with reactivity to anti-HBsAg antibodies. CONCLUSIONS: With this study, anti-HBc blood screening importance was confirmed.

[External evaluation of serology results in blood banks in Colombia]. / Evaluación externa de los resultados serológicos en los bancos de sangre de Colombia.

OBJECTIVE: To analyze the serological results found in Colombian blood banks that participate in the external quality program (EQP) of that country's National Institute of Health, in order to improve the quality of the screening of blood for the main serological markers of transfusion-transmitted infectious diseases. METHODS: Each blood bank received a panel of six sera with different reactivity and positivity to hepatitis B surface antigen (HBsAg), as well as to antibodies to HIV 1-2, Trypanosoma cruzi (the causative agent of Chagas' disease), Treponema pallidum (the causative agent of syphilis), hepatitis B core (HBc) antigen, hepatitis C virus (HCV), and human T-lymphotropic virus (HTLV). The screening techniques used were enzyme-linked immunosorbent assay (ELISA), microparticle enzyme immunoassay (MEIA), and hemagglutination. With the panel sera, the participating blood banks were asked to apply the same tests that they use on a daily basis to screen blood units and to send their results to the National Blood Banks Unit of the Colombian National Institute of Health. RESULTS: Of the 46 blood banks participating in the EQP, 43 of them (93%) returned their results within the requested timeframe. The ELISA test was the one that was used most often (83.0%). There were a total of 49 (5%) false positive results and 12 (3%) false negative results. Of those 12 false negative results, 6 of them corresponded to the detection of syphilis, 2 to Chagas' disease, 2 to anti-HBc antibodies, 1 to anti-HCV antibodies, and 1 to HBsAg. Eighty percent of the discordant results came from 23 blood banks that each collected fewer than 6 000 units of blood per year, and 15% came from 5 blood banks that collected 6 000 to 12 000 units per year. One of the blood banks that collected more than 12 000 units annually had three false positive results, and none of those larger blood banks had any false positive results. CONCLUSIONS: The percentage of false negative results (3%) found during the EQP can be considered high, since tests that are negative during blood screening are not repeated, and the decision to declare a unit of blood suitable for transfusion is based on that single result. There is a need to thoroughly review the procedures for screening blood in Colombia, particularly at the centers that performed poorly in this EQP exercise.

Evaluación externa de los resultados serológicos en los bancos de sangre de Colombia / External evaluation of serology results in blood banks in Colombia

OBJETIVO: Analizar los resultados serológicos obtenidos en los bancos de sangre colombianos que participan en el programa externo de calidad (PEC) con el fin de mejorar la calidad del tamizaje de la sangre según los principales marcadores serológicos de enfermedades infecciosas de posible transmisión sanguínea. MÉTODOS: Se evaluó un panel de seis sueros con diferente reactividad y positividad a anticuerpos contra los virus de la inmunodeficiencia humana (VIH) 1-2, el virus de la hepatitis C (VHC), Trypanosoma cruzi, Treponema pallidum y el virus linfotrópico de células T humanas (HTLV), y contra el antígeno de superficie del virus de la hepatitis B (HBsAg). Las técnicas de tamizaje utilizadas fueron el ensayo de inmunoadsorción enzimática (ELISA), el inmunoensayo enzimático de micropartículas (MEIA) y la hemaglutinación (HA). Se solicitó a los bancos de sangre participantes que aplicaran a los sueros las pruebas que diariamente realizaban para el tamizaje de unidades de sangre y que enviaran los resultados a la Coordinación Nacional de Bancos de Sangre del Instituto Nacional de Salud de Colombia. RESULTADOS: De 46 bancos de sangre que participaron, 43 (93 por ciento) devolvieron los resultados en el plazo indicado. La prueba de ELISA fue la más utilizada (83,02 por ciento). Se obtuvo un total de 49 (5 por ciento) resultados positivos falsos y 12 (3 por ciento) resultados negativos falsos. De estos últimos, 50 por ciento correspondieron a la detección de la sífilis; 16,7 por ciento a la de la enfermedad de Chagas; 16,7 por ciento a la de anticuerpos anti-HBc; 8,3 por ciento a la de anticuerpos anti-VHC y 8,3 por ciento a la del HBsAg. Ochenta por ciento de los resultados discordantes se presentaron en 23 bancos de sangre con un volumen de menos de 6 000 unidades de sangre al año, y 15 por ciento en 5 bancos de sangre con un volumen de 6 000 a 12 000 unidades de sangre al año. De los bancos de sangre que recogían más de 12 000 unidades anuales, solo uno notificó tres resultados positivos falsos. No se notificaron resultados negativos falsos. CONCLUSIONES: El porcentaje de resultados negativos falsos (3 por ciento) obtenidos durante el PEC puede considerarse elevado, ya que las pruebas que resultan negativas durante el tamizaje de los bancos de sangre no se repiten y la decisión de declarar una unidad de sangre apta para transfusión se basa en ese único resultado. Es preciso revisar minuciosamente los procedimientos para el tamizaje de la sangre,...