Adolescencia, adherencia y transición: Experiencia de un centro de trasplante renal pediátrico / Adolescence, adherence, and transition: Experience from a pediatric renal transplant center

Con el advenimiento de nuevas técnicas quirúrgicas y medicaciones inmunosupresoras la sobrevida de los niños trasplantados mejoró, llegando a la adultez. La continuidad de su tratamiento requiere un proceso planificado que permita su tránsito a un sistema de salud orientado al adulto. El objeto de este trabajo es mostrar la transición a centros de adultos en una cohorte de pacientes trasplantados renales en el Hospital Garrahan, describir sus características clínicas y demográficas, su evolución, y oportunidades de mejora implementadas. Debido a cambios médicos y su abordaje desde la interdisciplina, se dividió a la población en tres periodos: era 1 (1988-1999), era 2 (2000-2009), y era 3 (2010- 2023). En la era 1, 179 adolescentes continuaron su atención médica en un centro de adultos, 212 en la era 2 y 201 en la era 3. En la era 1 el seguimiento estaba coordinado por el nefrólogo de cabecera y eran consultados los servicios de Urología, Servicio Social y Salud Mental. En la era 2, se fortaleció el trabajo en interdisciplina y aún más a partir del 2011. Surgieron centros de trasplante de adultos que recibían adolescentes y médicos dedicados a ellos en forma preferencial. En la actualidad la transición comienza a los 12 años y progresa hasta los 18. El modelo implementado es la transición directa, entre el nefrólogo pediatra y el de adultos, con varias consultas secuenciales en ambos centros. Si bien la sobrevida del paciente e injerto mejoraron, el rechazo, asociado a no adherencia, es una asignatura por mejorar (AU)

With the advent of new surgical techniques and immunosuppressive medications, the survival of transplanted children has improved, allowing them to reach adulthood. The continuity of their treatment requires a planned process that facilitates their transition to an adult-oriented healthcare system. The aim of this study was to examine the transition to adult centers in a cohort of renal transplant patients at Garrahan Hospital, describing their clinical and demographic characteristics, their evolution, and the improvement opportunities implemented. Based on medical changes and the interdisciplinary approach, the population was divided into three periods: era 1 (1988- 1999), era 2 (2000-2009), and era 3 (2010-2023). In era 1, 179 adolescents continued their medical care in an adult center, 212 in era 2, and 201 in era 3. In era 1, follow-up was coordinated by the attending nephrologist with consultations from Urology, Social Services, and Mental Health Services. In era 2, interdisciplinary work was strengthened, and even more so since 2011. Adult transplant centers were created to receive adolescents with physicians dedicated to their care on a preferential basis. Currently, the transition begins at 12 years of age and progresses up to 18. The implemented model involves direct transition between the pediatric nephrologist and the adult nephrologist, with several sequential consultations in both centers. Although patient and graft survival have improved, rejection associated with non-adherence remains an area for improvement

Bacterial diversity in high Andean grassland soils disturbed with Lepidium meyenii crops evaluated by metagenomics / Diversidade bacteriana em solos de prados andinos elevados perturbados por culturas de Lepidium meyenii avaliadas por metagenômica

Soil quality is usually determined by its physical-chemical characteristics without taking into account the bacterial communities that play a fundamental role in the chemical decomposition of plant nutrients. In this context, the objective of the study was to evaluate bacterial diversity in high Andean grassland soils disturbed with Lepidium meyenii cultivation under different gradients of use (first, second and third use) and crop development (pre-sowing, hypocotyl development and post-harvest). The sampling was carried out in the Bombón plateau in the central Andes of Peru, during the rainy and low water seasons, by the systematic method based on a specific pattern assigned in a geometric rectangular shape at a depth of 0 - 20 cm. The characterization of the bacterial communities was carried out through the metagenomic sequencing of the 16S rRNA. 376 families of bacteria were reported, of which it was determined that there was a significant change in bacterial composition and distribution in relation to use pressure. There were no major changes due to the development of Lepidium meyenii. The families most sensitive to use pressure and soil poverty indicators were Verrucomicrobiaceae, Acidobacteraceae and Aakkermansiaceae.(AU)

A qualidade do solo é normalmente determinada pelas suas características físico-químicas sem ter em conta as comunidades bacterianas que desempenham um papel fundamental na decomposição química dos nutrientes das plantas. Neste contexto, o objetivo do estudo foi avaliar a diversidade bacteriana em solos de prados andinos elevados perturbados pelo cultivo de Lepidium meyenii sob diferentes gradientes de utilização (primeira, segunda e terceira utilizações) e desenvolvimento das culturas (pré-semeadura, desenvolvimento do hipocótilo e pós colheita). A amostragem foi realizada no planalto de Bombón, nos Andes centrais do Peru, durante as estações das chuvas e das águas baixas, pelo método sistemático baseado num padrão específico atribuído em forma geométrica retangular a uma profundidade de 0 - 20 cm. A caracterização das comunidades bacterianas foi realizada através da sequenciação metagenômica do rRNA 16S. Foram relatadas 376 famílias de bactérias, das quais se verificou uma alteração significativa na composição e distribuição bacteriana em relação à pressão de utilização. Não se registaram grandes alterações devido ao desenvolvimento do Lepidium meyenii. As famílias mais sensíveis à utilização de indicadores de pressão e pobreza do solo foram as Verrucomicrobiaceae, Acidobacteraceae e Aakkermansiaceae.(AU)

Bacterial diversity in high Andean grassland soils disturbed with Lepidium meyenii crops evaluated by metagenomics / Diversidade bacteriana em solos de prados andinos elevados perturbados por culturas de Lepidium meyenii avaliadas por metagenômica

Soil quality is usually determined by its physical-chemical characteristics without taking into account the bacterial communities that play a fundamental role in the chemical decomposition of plant nutrients. In this context, the objective of the study was to evaluate bacterial diversity in high Andean grassland soils disturbed with Lepidium meyenii cultivation under different gradients of use (first, second and third use) and crop development (pre-sowing, hypocotyl development and post-harvest). The sampling was carried out in the Bombón plateau in the central Andes of Peru, during the rainy and low water seasons, by the systematic method based on a specific pattern assigned in a geometric rectangular shape at a depth of 0 - 20 cm. The characterization of the bacterial communities was carried out through the metagenomic sequencing of the 16S rRNA. 376 families of bacteria were reported, of which it was determined that there was a significant change in bacterial composition and distribution in relation to use pressure. There were no major changes due to the development of Lepidium meyenii. The families most sensitive to use pressure and soil poverty indicators were Verrucomicrobiaceae, Acidobacteraceae and Aakkermansiaceae.

A qualidade do solo é normalmente determinada pelas suas características físico-químicas sem ter em conta as comunidades bacterianas que desempenham um papel fundamental na decomposição química dos nutrientes das plantas. Neste contexto, o objetivo do estudo foi avaliar a diversidade bacteriana em solos de prados andinos elevados perturbados pelo cultivo de Lepidium meyenii sob diferentes gradientes de utilização (primeira, segunda e terceira utilizações) e desenvolvimento das culturas (pré-semeadura, desenvolvimento do hipocótilo e póscolheita). A amostragem foi realizada no planalto de Bombón, nos Andes centrais do Peru, durante as estações das chuvas e das águas baixas, pelo método sistemático baseado num padrão específico atribuído em forma geométrica retangular a uma profundidade de 0 - 20 cm. A caracterização das comunidades bacterianas foi realizada através da sequenciação metagenômica do rRNA 16S. Foram relatadas 376 famílias de bactérias, das quais se verificou uma alteração significativa na composição e distribuição bacteriana em relação à pressão de utilização. Não se registaram grandes alterações devido ao desenvolvimento do Lepidium meyenii. As famílias mais sensíveis à utilização de indicadores de pressão e pobreza do solo foram as Verrucomicrobiaceae, Acidobacteraceae e Aakkermansiaceae.

Bacterial diversity in high Andean grassland soils disturbed with Lepidium meyenii crops evaluated by metagenomics / Diversidade bacteriana em solos de prados andinos elevados perturbados por culturas de Lepidium meyenii avaliadas por metagenômica

Soil quality is usually determined by its physical-chemical characteristics without taking into account the bacterial communities that play a fundamental role in the chemical decomposition of plant nutrients. In this context, the objective of the study was to evaluate bacterial diversity in high Andean grassland soils disturbed with Lepidium meyenii cultivation under different gradients of use (first, second and third use) and crop development (pre-sowing, hypocotyl development and post-harvest). The sampling was carried out in the Bombón plateau in the central Andes of Peru, during the rainy and low water seasons, by the systematic method based on a specific pattern assigned in a geometric rectangular shape at a depth of 0 - 20 cm. The characterization of the bacterial communities was carried out through the metagenomic sequencing of the 16S rRNA. 376 families of bacteria were reported, of which it was determined that there was a significant change in bacterial composition and distribution in relation to use pressure. There were no major changes due to the development of Lepidium meyenii. The families most sensitive to use pressure and soil poverty indicators were Verrucomicrobiaceae, Acidobacteraceae and Aakkermansiaceae.

A qualidade do solo é normalmente determinada pelas suas características físico-químicas sem ter em conta as comunidades bacterianas que desempenham um papel fundamental na decomposição química dos nutrientes das plantas. Neste contexto, o objetivo do estudo foi avaliar a diversidade bacteriana em solos de prados andinos elevados perturbados pelo cultivo de Lepidium meyenii sob diferentes gradientes de utilização (primeira, segunda e terceira utilizações) e desenvolvimento das culturas (pré-semeadura, desenvolvimento do hipocótilo e pós colheita). A amostragem foi realizada no planalto de Bombón, nos Andes centrais do Peru, durante as estações das chuvas e das águas baixas, pelo método sistemático baseado num padrão específico atribuído em forma geométrica retangular a uma profundidade de 0 - 20 cm. A caracterização das comunidades bacterianas foi realizada através da sequenciação metagenômica do rRNA 16S. Foram relatadas 376 famílias de bactérias, das quais se verificou uma alteração significativa na composição e distribuição bacteriana em relação à pressão de utilização. Não se registaram grandes alterações devido ao desenvolvimento do Lepidium meyenii. As famílias mais sensíveis à utilização de indicadores de pressão e pobreza do solo foram as Verrucomicrobiaceae, Acidobacteraceae e Aakkermansiaceae.

Bacterial diversity in high Andean grassland soils disturbed with Lepidium meyenii crops evaluated by metagenomics

Abstract Soil quality is usually determined by its physical-chemical characteristics without taking into account the bacterial communities that play a fundamental role in the chemical decomposition of plant nutrients. In this context, the objective of the study was to evaluate bacterial diversity in high Andean grassland soils disturbed with Lepidium meyenii cultivation under different gradients of use (first, second and third use) and crop development (pre-sowing, hypocotyl development and post-harvest). The sampling was carried out in the Bombón plateau in the central Andes of Peru, during the rainy and low water seasons, by the systematic method based on a specific pattern assigned in a geometric rectangular shape at a depth of 0 - 20 cm. The characterization of the bacterial communities was carried out through the metagenomic sequencing of the 16S rRNA. 376 families of bacteria were reported, of which it was determined that there was a significant change in bacterial composition and distribution in relation to use pressure. There were no major changes due to the development of Lepidium meyenii. The families most sensitive to use pressure and soil poverty indicators were Verrucomicrobiaceae, Acidobacteraceae and Aakkermansiaceae.

Resumo A qualidade do solo é normalmente determinada pelas suas características físico-químicas sem ter em conta as comunidades bacterianas que desempenham um papel fundamental na decomposição química dos nutrientes das plantas. Neste contexto, o objetivo do estudo foi avaliar a diversidade bacteriana em solos de prados andinos elevados perturbados pelo cultivo de Lepidium meyenii sob diferentes gradientes de utilização (primeira, segunda e terceira utilizações) e desenvolvimento das culturas (pré-semeadura, desenvolvimento do hipocótilo e pós-colheita). A amostragem foi realizada no planalto de Bombón, nos Andes centrais do Peru, durante as estações das chuvas e das águas baixas, pelo método sistemático baseado num padrão específico atribuído em forma geométrica retangular a uma profundidade de 0 - 20 cm. A caracterização das comunidades bacterianas foi realizada através da sequenciação metagenômica do rRNA 16S. Foram relatadas 376 famílias de bactérias, das quais se verificou uma alteração significativa na composição e distribuição bacteriana em relação à pressão de utilização. Não se registaram grandes alterações devido ao desenvolvimento do Lepidium meyenii. As famílias mais sensíveis à utilização de indicadores de pressão e pobreza do solo foram as Verrucomicrobiaceae, Acidobacteraceae e Aakkermansiaceae.

Bacterial diversity in high Andean grassland soils disturbed with Lepidium meyenii crops evaluated by metagenomics.

Soil quality is usually determined by its physical-chemical characteristics without taking into account the bacterial communities that play a fundamental role in the chemical decomposition of plant nutrients. In this context, the objective of the study was to evaluate bacterial diversity in high Andean grassland soils disturbed with Lepidium meyenii cultivation under different gradients of use (first, second and third use) and crop development (pre-sowing, hypocotyl development and post-harvest). The sampling was carried out in the Bombón plateau in the central Andes of Peru, during the rainy and low water seasons, by the systematic method based on a specific pattern assigned in a geometric rectangular shape at a depth of 0 - 20 cm. The characterization of the bacterial communities was carried out through the metagenomic sequencing of the 16S rRNA. 376 families of bacteria were reported, of which it was determined that there was a significant change in bacterial composition and distribution in relation to use pressure. There were no major changes due to the development of Lepidium meyenii. The families most sensitive to use pressure and soil poverty indicators were Verrucomicrobiaceae, Acidobacteraceae and Aakkermansiaceae.

Microscopic Study of Surface Microtopographic Characteristics of Dental Implants.

OBJECTIVE: To determine and compare the micro topographic characteristics of dental implants submitted to different surface treatments, using scanning electron microscopy (SEM). MATERIALS AND METHODS: Implants were divided into 7 groups of 3 specimens each, according to the surface treatment used: group 1: Osseotite, BIOMET 3i; group 2: SLA surface, Institut Straumann AG; group 3: Oxalife surface, Tree-Oss implant; group 4: B&W implant surface; group 5: Q-implant surface; group 6: ML implant surface; group 7: RBM surface, Rosterdent implant. The surfaces were examined under SEM (Carl Zeiss FE-SEM-SIGMA). Image Proplus software was used to determine the number and mean diameter of pores per area unit (mm). The data obtained were analyzed with the Mann-Whitney test. A confocal laser microscope (LEXT-OLS4100 Olympus) was used to conduct the comparative study of surface roughness (Ra). Data were analyzed using Tukey's HSD test. RESULTS: The largest average pore diameter calculated in microns was found in group 5 (3.45 µm+/-1.91) while the smallest in group 7 (1.47µm+/-1.29). Significant differences were observed among each one of the groups studied (p<0.05). The largest number of pores/mm(2) was found in group 2 (229343) and the smallest number in group 4 (10937). Group 2 showed significant differences regarding the other groups (p<0.05). The greatest roughness (Ra) was observed in group 2 (0.975µm+/-0.115) and the smallest in group 4 (0.304µm+/-0.063). Group 2 was significantly different from the other groups (p<0.05). CONCLUSION: The micro topography observed in the different groups presented dissimilar and specific features, depending on the chemical treatment used for the surfaces..

Edad al momento del trasplante: ¿Quiénes tienen riesgo de mala evolución ? / Age at transplantation: who are at risk of a poor outcome ?

Introducción: Si bien la sobrevida de paciente e injerto en niños con trasplante renal (TxR) ha mejorado, algunos sugieren que la edad al TxR es predictora de malos resultados, y los mayores tendrían peor evolución. Objetivo: Definir sobrevida de paciente e injerto según edad al TxR, y factores pronósticos de fracaso en aquellos con peor evolución. Material y métodos: Cohorte retrospectivo de todos los pacientes con TxR en el Hospital Garrahan desde el 01-01-2002 hasta el 01-03-2016. Resultados: de 431 pacientes, 44, (10%) tenían < 6a, 179 (42%)> 6 y <12 y 208 (48%) ≥12 años. La sobrevida del paciente a 8 años fue 97%, 99% y 95% (p=0,2), y la del injerto de: 86%, 69% y 30% respectivamente (p=<0,001). En los ≥ de 12 años, con peor evolución, se incluyeron al análisis univariado como factores de riesgo de pérdida de injerto: GSFS como causa de IRC : HR: 9,4; (p<0,001), Rechazo Agudo (RA) temprano: HR: 8,1; (p<0,001), RA tardío: HR: 4,3; (p<0.001), DGF: HR: 4,1; (p<0,001), No adherencia: HR: 2,3; (p=0,02), Edad de DC > 35a: HR: 1,95 (p=0,1), Tiempo en diálisis: HR: 1,1 (p=0,1), Número de incompatibilidades HLAB y HLADR: HR: 0,8 (p=0,3), Tiempo de Isquemia : 0,9 (p=0,5), Sexo del receptor: HR:0,8 (p=0,6), Donante Cadavérico: HR: 1,2; (p=0,6), 2do TxR : HR: 1,2; (p=0,7). En análisis multivariado: RA tardío: HR: 12,9 (p<0,001), GSFS como causa de IRC: HR: 12,5 (p<0,001), RA temprano: HR: 9 (p<0,001), y DGF: HR: 4,9 (p<0,001). Conclusión: la sobrevida del injerto en adolescentes es inferior. Merecen atención, la prevención de la no adherencia asociada a rechazo, el paciente con GSFS y el retardo de la función pos TxR (AU)

Introduction: Although patient and graft survival of children with a kidney transplantation (KTx) has improved, it has been suggested that older age at KTx is a predictive factor of poor outcome. Aim: To evaluate patient and graft survival according to age at KTx and define predictive factors in those with a poor outcome. Material and methods: A retrospective cohort study was conducted in all patients who underwent KTx at Garrahan Hopital between 01-01-2002 and 01-03-2016. Results: Of 431 patients, 44 (10%) were <6yr, 179 (42%) >6yr, and <12yr, and 208 (48%) ≥12yr. Eight-year patient survival was 97%, 99%, and 95% (p=0.2) and graft survival was 86%, 69%, and 30% (p=<0.001), respectively. In children ≥12 yr, with a worse outcome, the following risk factors of graft loss were included in univariate analysis: FSGS-related CFR: HR: 9.4; (p<0.001), early acute rejection (AR): HR: 8.1; (p<0.001), late AR: HR: 4.3; (p<0.001), DGF: HR: 4.1; (p<0.001), non-adherence: HR: 2.3; (p=0.02), age of deceased donor >35yr: HR: 1.95 (p=0.1), time on dialysis: HR: 1.1 (p=0.1), number of HLA-B and HLA-DR mismatches: HR: 0.8 (p=0.3), cold ischemia time: 0.9 (p=0.5), recipient sex: HR:0.8 (p=0.6), deceased donor: HR: 1.2; (p=0.6), second KTx: HR: 1.2; (p=0.7; and in multivariate analysis: late AR: HR: 12.9 (p<0.001), FSGS-related CFR: HR: 12.5 (p<0.001), early AR: HR: 9 (p<0.001), and DGF: HR: 4.9 (p<0.001). Conclusion: Graft survival is lower in adolescents. Prevention of rejection associated with non-adherence, FSGS, and post-KTx DGF should be taken into account (AU)

Glomerulonefritis con semilunas / Glomerulonephritis with crescents

La glomerulonefritis rápidamente progresiva (GNRP) es una entidad caracterizada por una brusca y progresiva declinación de la función renal y por la presencia en la biopsia renal de proliferación celular extra capilar (semilunas) que ocupan el espacio de Bowmans. Nosotros analizamos en forma retrospectiva 37 niños con diagnóstico de GNRP (50% o más de los glomérulos con semilunas) asistidos en esta institución durante los últimos 20 años. El propósito fue evaluar la presentación clínica e histopatológica, etiología, evolución y factores de mal pronóstico. La edad media al diagnóstico fue de 11 ± 3,5 años. Los síntomas de presentación fueron: hematuria 100% de los casos (hematuria macroscópica 56%); hipertensión arterial 92%; proteinuria 88%; síndrome nefrótico 57%. Fue necesaria diálisis al ingreso en el 64,1% de los casos. Las biopsias renales fueron realizadas a 38 ± 26 días desde el comienzo de los síntomas. El porcentaje de glomérulos que presentaron semilunas fue del 81,4%; las mismas fueron epiteliales en el 28,3% de los casos; fibroepiteliales en el 21,8% y fibrosas en el 31,3%. En el 75,8% de las biopsias se encontró fibrosis intersticial y atrofia tubular moderada y/o severa. La inmunofluorescencia no mostro depósitos de complejos inmunes (GN pauci-inmune) en el 40,6% de las biopsias, mostró depósitos granulares de complejos inmunes en el 48,6% y depósitos lineales de anticuerpos anti membrana basal glomerular (Goodpasture´s) en el 10,8%. El tratamiento fue iniciado a 36 ± 32 días desde el comienzo de los síntomas. Todos los pacientes recibieron tratamiento de sostén; en 29 de ellos se indicaron además esteroides y ciclofosfamida, y en 5 solo esteroides. El tiempo medio de seguimiento fue de 4,6 ± 3,9 años. La sobrevida de los pacientes al final del seguimiento fue del 87% (IC95% 55-97%) y la sobrevida del órgano fue del 17% (IC95% 7-38%). Por análisis multivariado encontramos que la fibrosis intersticial y atrofia tubular moderada y/o severa fue el único factor que se relacionó con pérdida del órgano (OR: 14,6 IC95%2,6-80) p= 0,001. Nuestros resultados muestran que la GNRP en niños es una entidad con pobre pronóstico en relación a la función renal. El factor de peor pronóstico que puede llevar a la pérdida del órgano es el compromiso túbulo-intersticial (AU)

Rapidly progressive glomerulonephritis (RPGN) is characterized by a sudden and progressive decrease of kidney function and extra-capillary cell proliferation (crescents) occupying the Bowman's space on the biopsy. We retrospectively analysed 37 children with RPGN (50% or more of glomeruli with crescents) seen at our institution over the past 20 years. The purpose of the study was to evaluate clinical and histopathological presentation, etiology, outcome, and factors of poor prognosis. Mean age at diagnosis was 11 ± 3.5 years. Presenting symptoms were: hematuria in 100% of the cases (macroscopic hematuria 56%); arterial hypertension in 92%; proteinuria in 88%; and nephrotic syndrome in 57%. Dialysis was necessary on admission in 64.1% of the cases. Kidney biopsies were performed at 38 ± 26 days after symptom onset. The percentage of glomeruli that presented crescents was 81.4%; they were epithelial in 28.3% of the cases, fibroepithelial in 21.8%, and fibrous in 31.3%. In 75.8% of the biopsies interstitial fibrosis and moderate and/or severe tubular atrophy was found. Immunofluorescence techniques did not show immune complex deposits (pauci-immune GN) in 40.6% of the biopsies. Granular deposits of immune complexes were found in 48.6% and linear anti-glomerular basement membrane deposits (Goodpasture´s) in 10.8%. Treatment was started 36 ± 32 days after symptom onset. All patients received support treatment; in 29 steroids and cyclophosphamide were also indicated, and in 5 steroids only. Mean time of follow-up was 4.6 ± 3.9 years. Patient survival at the end of follow-up was 87% (95%CI 55-97%) and organ survival was 17% (95%CI 7-38%). On multivariate analysis we found that interstitial fibrosis and moderate and/or severe tubular atrophy was the only factor related to organ loss (OR: 14.6; 95%CI 2.6-80) p= 0.001). Our results show that RPGN in children has a poor prognosis regarding kidney function. Tubulo-interstitial involvement is the factor of poor prognosis that may lead to organ loss (AU)

Sobrevida de pacientes e injerto en niños con trasplante renal: experiencia del Hospital Garrahan en dos períodos / Patient and graft survival in children with a kidney transplant: The experience at Garrahan Hospital over two periods

En adultos y niños con trasplante renal (TxR) la sobrevida de paciente e injerto ha mejorado. En Argentina no existen datos de sobrevida en niños con TxR en diferentes décadas. El objeto de este trabajo fue valorar en niños con TxR sobrevida de paciente e injerto y analizar causas de muerte, perdida de injerto y factores de riesgo de pérdida. Dado que desde el año 2001 se unificaron prácticas de diagnóstico y tratamiento, se compararon dos periodos: 1988-2000 y 2001-2015. Se incluyeron 773 niños. A 1, 3, 5, 7 y 10 años, En TxR de DV (n=327), la sobrevida del paciente fue de 99%, 99%, 98%, 95%, 95% vs 100% y 96%, 96%, 96% y 96% (p=0.74); la del injerto de 97%, 91%, 85%, 78% y 67% vs 95%, 88%, 85%, 81% y 76% (p=0.81). En TxR de DC (n=446) la sobrevida de paciente fue de 97%, 93%, 90%, 89% y 87% en el 1er. periodo vs. 100%, 99% y 98% 98% y 98% en el 2do (p<0.001); la del injerto de 83%, 75%, 68%, 64% y 52% vs. 95%, 87%, 83%, 76% y 61% respectivamente (p<0. 001). El Rechazo Crónico fue la 1er causa de perdida (61% vs 62%); la 2da la muerte del paciente con injerto funcionante. La sepsis bacteriana fue la 1era causa de muerte (56% vs 67%). Ningún niño falleció por neoplasia entre el 2001 y 2015. En DV, fueron predictores de perdida de injerto: DGF (HR: 4.8; p<0.001), edad al TxR > 12 años (HR: 2.7; p=0.002) y RA tardío (HR: 2.1; p=0.009). En DC la necesidad de diálisis en la 1er semana post TxR (DGF): (HR: 4.4; p<0.001), el rechazo agudo (RA) tardío (HR: 3.7; p<0.001), GSFS como causa de IRC (HR: 2.5; p=0.01), y RA temprano (HR: 2.2; p=0.02). Conclusión: En el 2do periodo la sobrevida de paciente e injerto los TxR con DC mejoro, y en los TxR con DV no tuvo cambios. El rechazo crónico continúa siendo la 1era causa de perdida. Ningún paciente tuvo neoplasia (AU)

Patient and graft survival in kidney transplantation (KTx) has improved. In Argentina there are no data comparing transplant outcomes in children over different eras. The aim of this study was to evaluate patient and graft survival in children with KTx and to analyze cause of death, graft loss, and risk factors of graft loss. As diagnostic and treatment practices were unified in 2001, two periods were compared: 1988-2000 and 2001-2015. Overall, 773 children were included. Survival at 1, 3, 5, 7, and 10 years after a living-related donor (LRD) KTx was 99%, 99%, 98%, 95%, 95% vs 100% y 96%, 96%, 96% and 96% (p=0.74); graft survival was 97%, 91%, 85%, 78% y 67% vs 95%, 88%, 85%, 81%, and 76% (p=0.81). Patient survival after deceased donor (DD) KTx (n=446) was 97%, 93%, 90%, 89%, and 87% in the 1st period vs. 100%, 99% y 98% 98%, and 98% in the 2nd (p<0.001); graft survival was 83%, 75%, 68%, 64%, and 52% vs. 95%, 87%, 83%, 76%, and 61%, respectively (p<0. 001). Chronic rejection was the first cause of graft loss (61% vs 62%); the second was death of the patient with a functioning graft. Bacterial sepsis was the first cause of death (56% vs 67%). None of the patients died because of malignancies between 2001 and 2015. Among LRD transplants predicting factors of graft loss were: DGF (HR: 4.8; p<0.001), age at KTx >12 years (HR: 2.7; p=0.002), and late acute rejection (AR) (HR: 2.1; p=0.009). Among DD need for dialysis in the first week post-KTx (DGF): (HR: 4.4; p<0.001), late AR (HR: 3.7; p<0.001), FSGS-related CFR (HR: 2.5; p=0.01), and early AR (HR: 2.2; p=0.02). Conclusion: In the second period patient and graft survival after DD improved, while that of KTx with LRD remained unchanged. Chronic rejection continues being the first cause of graft loss. None of the patients developed malignancies.

First epidemiologic study in Argentina of the prevalence of BK viruria in kidney transplant patients.

BACKGROUND: The worldwide seroprevalence of human BK polyomavirus (BKV) in adults is 80%. About 10%-60% of renal transplant recipients experience BKV infection, nephropathy of the graft may occur in 5% of the cases, and up to 45% lose the graft. The aim of this work was to describe the prevalence of BK viruria during the 1st year after transplantation. METHODS: An epidemiologic multicenter cross-sectional study was carried out in consecutive patients at each site with kidney transplantation from August 2011 to July 2012. Clinically significant viruria was defined as >10(7) copies/mL. Viral DNA was extracted with the use of silica columns. Quantification was performed with the use of real-time polymerase chain reaction with primers that amplify a fragment of the large T-antigen gene and with a specific Taqman-MGB probe for BKV. For each assay, a standard curve with a quantified plasmid was included. RESULTS: Of 402 renal transplant recipients at 18 renal transplant sites, we analyzed 382; median age was 46.33 years, and 46.40% were female. The median of the temporal distribution for urine samples was 153 days. BK virus was detected in 50/382 samples (13%), 18 with values >10(7) copies/mL (4.7%). The median of the distribution of positive values was 123 days and the highest frequency of positive values was in months 3-7. The conditions of recipient older than 34 years and donor older than 41 years were the only ones that showed statistically significant association with BK viruria. No association with any specific immunosuppressive drug was observed. CONCLUSIONS: This is the first multicenter study conducted in Argentina to determine the prevalence of BK viruria in renal transplant recipients. Because of the growing number of the population susceptible to this infection, it is important to register and describe data about its epidemiology and associated risk factors.

Anomalías nefro-urologicas en el riñón contralateral de pacientes con displasia renal multiquística unilateral / Urological and nephrological abnormalities in the contralateral kidney in patients with unilateral multicystic dysplastic kidney

La displasia renal multiquística unilateral (DRMU) es la enfermedad quística renal más frecuente en pediatría. En estos pacientes, la función renal depende exclusivamente del riñón único funcionante contralateral. El objetivo de este trabajo retrospectivo fue determinar la prevalencia y tipo de anomalías nefro-urológicas en el riñón contralateral funcionante de 103 pacientes con DRMU atendidos en el Hospital Nacional de Pediatría Prof. Dr. Juan P. Garrahan entre 1995-2008. Se analizaron sólo aquellos niños que tenían ecografía renal y vesical, cistouretrografía miccional (CUGM) y centellograma renal con ácido dimercaptosuccínico (DMSA-Tc99m). Por ecografía se encontraron anomalías en el riñón contralateral funcionante en el 18.5%. Las más frecuentes fueron dilatación de la vía urinaria (6.8%) y aumento de la ecogenicidad (6.8%). La CUGM detectó la presencia de reflujo vesicoureteral en el riñón contralateral en 11 niños (10.7%), la mayoría leve a moderado. El centellograma renal con DMSA-Tc99m demostró escaras en 12 niños (11.6%). Los resultados muestran que el 23.3% de los pacientes con DRMU tienen alguna anomalía nefro-urológica en el riñón único funcionante contralateral.

Anomalías nefro-urologicas en el riñón contralateral de pacientes con displasia renal multiquística unilateral / Urological and nephrological abnormalities in the contralateral kidney in patients with unilateral multicystic dysplastic kidney

La displasia renal multiquística unilateral (DRMU) es la enfermedad quística renal más frecuente en pediatría. En estos pacientes, la función renal depende exclusivamente del riñón único funcionante contralateral. El objetivo de este trabajo retrospectivo fue determinar la prevalencia y tipo de anomalías nefro-urológicas en el riñón contralateral funcionante de 103 pacientes con DRMU atendidos en el Hospital Nacional de Pediatría Prof. Dr. Juan P. Garrahan entre 1995-2008. Se analizaron sólo aquellos niños que tenían ecografía renal y vesical, cistouretrografía miccional (CUGM) y centellograma renal con ácido dimercaptosuccínico (DMSA-Tc99m). Por ecografía se encontraron anomalías en el riñón contralateral funcionante en el 18.5%. Las más frecuentes fueron dilatación de la vía urinaria (6.8%) y aumento de la ecogenicidad (6.8%). La CUGM detectó la presencia de reflujo vesicoureteral en el riñón contralateral en 11 niños (10.7%), la mayoría leve a moderado. El centellograma renal con DMSA-Tc99m demostró escaras en 12 niños (11.6%). Los resultados muestran que el 23.3% de los pacientes con DRMU tienen alguna anomalía nefro-urológica en el riñón único funcionante contralateral. (AU)

The actin filament network associated to Sertoli cell ectoplasmic specializations

Junctional devices in Sertoli cells conform the blood-testis barrier and play a key role in maturation and differentiation of germ cells. The spacial distribution of ectoplasmic specializations of Sertoli cells was studied by beta-actin immunolabelling, using laser confocal and transmission electron microscopy. For confocal microscopy, beta-actin immunolabelling of ectoplasmic specializations was studied over the background of either prosaposin or glutaredoxin immunolabelling of the Sertoli cytoplasm. Labelling was found near the basal lamina, surrounding early spermatocytes (presumably in leptotene-zygotene) or at one of two levels in the seminiferous epithelium: (1) around deep infoldings of the Sertoli cell cytoplasm, in tubular stages before spermiation, and (2) in the superficial part of the seminiferous epithelium, in tubular stages after or during spermiation. For transmission electron microscopy, beta-actin immunolabelling of ectoplasmic specializations was also used. Ectoplasmic specializations were found at two different levels of the seminiferous epithelium. We also used freeze fracture to analyze the characteristics of tubulo-bulbar complexes, a known component of apical ectoplasmic specializations. Also, these different approaches allowed us to study the complex arrangement of the actin cytoskeleton of Sertoli cells branches, which surround germ cells in different stages of the spermatogenic cycle. Our results show a consistent labelling for beta-actin before, during and after the release of spermatozoa in the tubular lumen (spermiation) suggesting a significant role of the actin network in spermatic cell differentiation. In conclusion, significant interrelations among the beta-actin network, the junctional complexes of the blood-testis barrier and the ectoplasmic specializations were detected at different stages of the seminiferous cycle.

The actin filament network associated to Sertoli cell ectoplasmic specializations

Junctional devices in Sertoli cells conform the blood-testis barrier and play a key role in maturation and differentiation of germ cells. The spacial distribution of ectoplasmic specializations of Sertoli cells was studied by beta-actin immunolabelling, using laser confocal and transmission electron microscopy. For confocal microscopy, beta-actin immunolabelling of ectoplasmic specializations was studied over the background of either prosaposin or glutaredoxin immunolabelling of the Sertoli cytoplasm. Labelling was found near the basal lamina, surrounding early spermatocytes (presumably in leptotene-zygotene) or at one of two levels in the seminiferous epithelium: (1) around deep infoldings of the Sertoli cell cytoplasm, in tubular stages before spermiation, and (2) in the superficial part of the seminiferous epithelium, in tubular stages after or during spermiation. For transmission electron microscopy, beta-actin immunolabelling of ectoplasmic specializations was also used. Ectoplasmic specializations were found at two different levels of the seminiferous epithelium. We also used freeze fracture to analyze the characteristics of tubulo-bulbar complexes, a known component of apical ectoplasmic specializations. Also, these different approaches allowed us to study the complex arrangement of the actin cytoskeleton of Sertoli cells branches, which surround germ cells in different stages of the spermatogenic cycle. Our results show a consistent labelling for beta-actin before, during and after the release of spermatozoa in the tubular lumen (spermiation) suggesting a significant role of the actin network in spermatic cell differentiation. In conclusion, significant interrelations among the beta-actin network, the junctional complexes of the blood-testis barrier and the ectoplasmic specializations were detected at different stages of the seminiferous cycle

The actin filament network associated to Sertoli cell ectoplasmic specializations

Junctional devices in Sertoli cells conform the blood-testis barrier and play a key role in maturation and differentiation of germ cells. The spacial distribution of ectoplasmic specializations of Sertoli cells was studied by beta-actin immunolabelling, using laser confocal and transmission electron microscopy. For confocal microscopy, beta-actin immunolabelling of ectoplasmic specializations was studied over the background of either prosaposin or glutaredoxin immunolabelling of the Sertoli cytoplasm. Labelling was found near the basal lamina, surrounding early spermatocytes (presumably in leptotene-zygotene) or at one of two levels in the seminiferous epithelium: (1) around deep infoldings of the Sertoli cell cytoplasm, in tubular stages before spermiation, and (2) in the superficial part of the seminiferous epithelium, in tubular stages after or during spermiation. For transmission electron microscopy, beta-actin immunolabelling of ectoplasmic specializations was also used. Ectoplasmic specializations were found at two different levels of the seminiferous epithelium. We also used freeze fracture to analyze the characteristics of tubulo-bulbar complexes, a known component of apical ectoplasmic specializations. Also, these different approaches allowed us to study the complex arrangement of the actin cytoskeleton of Sertoli cells branches, which surround germ cells in different stages of the spermatogenic cycle. Our results show a consistent labelling for beta-actin before, during and after the release of spermatozoa in the tubular lumen (spermiation) suggesting a significant role of the actin network in spermatic cell differentiation. In conclusion, significant interrelations among the beta-actin network, the junctional complexes of the blood-testis barrier and the ectoplasmic specializations were detected at different stages of the seminiferous cycle

Disfunción crónica del injerto renal antes y después de la conversión de ciclosporina a sirolimus / Chronic allograft failure before and after a switch from cyclosporine to sirolimus

El propósito de este estudio fue evaluar la progresión de la disfunción crónica del injerto en receptores pediátricos de un TxR que recibían CsA como parte de su inmunosupresión y ésta fue reemplazada por SRL, a causa de un lento y progresivo aumento de la creatinina sérica, signos histológicos de nefropatía crónica del trasplante y ausencia de rechazo agudo en la biopsia renal. Se empleó la inversa la de creatinina sérica (1/CrS) para estimar la velocidad de progresión de la disfunción crónica del injerto, durante el año previo al cambio de la medicación y dos años después del mismo. Analizamos 26 pacientes trasplantados a los 9.76 ± 3.9 años que recibían CsA y en quienes se reemplazó ésta por SRL a los 57.07 ± 39.1 meses post trasplante. La pendiente de la 1/CrS disminuyó de -0.016 mg/dl/mes antes del cambio a -0.002 mg/dl/mes durante el primer año después del mismo y a -0.001 mg/dl/mes durante el segundo año (p= 0.007). Cuando separamos los pacientes según el grado de NCT que mostraban las biopsias renales, aquellos pacientes que tenían NCT grado I (n= 11), la pendiente de la 1/CrS mejoró de -0.012 mg/dl/mes basal a -0.006 mg/dl/mes durante el primer año y a +0.001 mg/dl/mes durante el segundo año (p= 0.01). En cambio, los pacientes que tenían NCT grado II en sus biopsias, mostraron mejoría de la pendiente de la 1/CrS durante el primer año luego del cambio, pero la misma no fue sostenida ni significativa durante el segundo año de observación. Entre ambos grupos, las únicas variables que mostraron diferencias significativas fueron el filtrado glomerular y el tiempo post trasplante al momento del cambio de la inmunosupresión. Conclusión: nuestros resultados muestran una significativa disminución de la velocidad de progresión de la disfunción crónica del injerto cuando se reemplaza la CsA por SRL en pacientes con mínimos cambios morfológicos en la biopsia renal y con un filtrado glomerular cercano a 60 ml/min/1.73.

Seguridad y eficacia de la biopsia renal percutánea / Safety and efficacy of percutaneous renal biopsy

Se realizó una evaluación de la seguridad y eficacia del procedimiento de la biopsia renal percutánea BRP de riñones nativos bajo control ecográfico simultáneo. Se revisaron las historias clínicas de todos los pacientes que fueron biopsiados en el período comprendido entre enero de 2005 y diciembre de 2008 en el Servicio de Nefrología del Hospital de Pediatría Juan P. Garrahan. Se excluyeron del análisis los procedimientos realizados bajo anestesia general y en riñón transplantado. Se evaluaron 117 procedimientos realizados en 114 pacientes: 59 varones (50.4%) y 55 mujeres (49.6%). Las indicaciones más frecuentes de BRP fueron: proteinuria masiva o significativa con o sin hematuria 45 (38,6%), Lupus Eritematoso Sistémico 32 (27.4%) y síndrome nefrótico cortico-resistente 23 (20%); otras menos frecuentes estuvieron representadas por: Púrpura de Schönlein-Henoch 7 (6%), insuficiencia renal aguda (IRA) 5 (4%) e insuficiencia renal crónica (IRC) 5 (4%). No se produjeron eventos adversos (EA) en 97 (83%) procedimientos. En 20 (17%), se produjeron EA. Los EA no serios fueron 9: microhematuria (n=3), macrohematuria (n=3) y dolor lumbar (n=3). Los 11 restantes fueron EAS (serios) que correspondieron a hematomas perirrenales de los cuales 2 requirieron transfusión de glóbulos rojos. Las muestras obtenidas fueron suficientes para el diagnóstico en 113 procedimientos (97%), con un número de glomérulos de 30 ± 11. Los resultados demostraron que el procedimiento de BRP con disparador automático, anestesia local y control ecográfico simultáneo es seguro y eficaz. El número de EAS registrados en este estudio es similar o menor según las series analizadas. A diferencia de la publicación internacional en nuestro centro se realiza el procedimiento con el paciente despierto (AU)

In this study we evaluated the safety and efficacy of ultrasound-guided percutaneous renal biopsy (PRB) of native kidneys. The clinical charts of all patients that underwent PRB between January 2005 and December 2008 at the Department of Nephrology of the Pediatric Hospital Juan P. Garrahan were reviewed. Procedures performed under general anesthesia and in transplanted kidneys were excluded from the analysis. We evaluated 117 procedures performed in 114 patients: 59 were male (50.4%) and 55 female (49.6%). The most frequent indications for PRB were: massive or significant proteinuria with or without hematuria 45 (38,6%), systemic lupus erythematosus 32 (27.4%), and steroid-resistant nephrotic syndrome 23 (20%); other less frequent indications were: Henoch-Schönlein purpura 7 (6%), acute renal insufficiency (ARI) 5 (4%), and chronic renal insufficiency (CRI) 5 (4%). No adverse events (AE) were observed in 97 (83%) procedures. AE were seen in 20 (17%). There were 9 minor AE: microhematuria (n=3), gross hematuria (n=3), and lumbar pain (n=3). Serious AE observed were perinephric hematoma in 11 patients of whom 2 required red blood cell transfusions. The sample size was sufficient for diagnosis in 113 procedures (97%), with a number of glomeruli of 30 ± 11. The results show that ultrasoundguided PRB with an automatic trigger and local anesthesia is a safe and effective procedure. The number of serious AE in this study is similar to or lower than reported in previous series. Unlike other international series, at our center the procedure is performed while the patient is awake (AU)

Trasplante renal 1988 - 2008 / Kidney transplantation 1988 2008

Evaluación retrospectiva de 575 trasplantes (TX), 64,3 por ciento con donante cadavérico (DC), en 550 pacientes (311 varones) edad por x: 10.8 más menos 4.2 años, efectuados entre 1988 y 2008. edad por de donante: DC 22.5 más menos 14 años y DVR: 37.3 más menos 7.7 años. Principales causas de IRC: nefropatía por reflujo: 34,1 por ciento, hipo-displasia: 15.1 por ciento, SUH; 12.9 por ciento, GSF: 9.82 por ciento, glomerulonefritis varias: 16.4 por ciento. Inmunosupresion: en la mayoría de los pacientes, Cicloporina A; Azatioprina o micofenolato mofetil o ácido micofenólico y esteroides con linfo o timoglobulina secuencia en TXDC y profilaxis con gaciclovir en riesgo de infección por CMV. La sobrevida actuarial funcional renal (SA) a 1.3 a 5 años fue 96.5 por ciento, 94.4 por ciento y 86,2 por ciento TX DVR y 90,1 por ciento, 85,5 por ciento y 77.6 por ciento TX DC, p= 0.04, similar a resultados en EEUU (NAPRCTS 1999 - 2002). La GSF con 45.5 por ciento de recurrencia del síndrome nefrótico, tuvo inferior SA al 5to año, p= 0.001, comparado con otras etiologías de IRC. Los TX sin diálisis (D) previa, p= 0.003. Tuvieron trombosis 2.61 por ciento de los TX, más frecuentes con DPCA pre tx que con hemo D o sin diálisis, p= 0.01, con TXDC, p= 0.02 y con TX de donantes < de 6 años, p = 0.02. Los pacientes que requirieron diálisis post trasplante, tuvieron mayor creatinina al año D: 1.8 más menos 2.27 mg/dl.SD: 1.19 más menos 1.2, p < 0.01, e inferior SA al quinto año, p=0.001. Con tiempo de isquemia fria superior a 24 horas, 31,6 por ciento de los DC necesitaron diálisis. El rechazo celular agudo se dianosticó en el 14,8 por ciento de los pacientes. Las causas más frecuentes de fracaso del trasplante fueron: nefropatía crónica (69,8 por ciento) asociado a inadecuada adherencia en 54.7 por ciento, trombosis (12.6 por ciento), recurrencia (5.9 por ciento), ausencia de función (5 por ciento) rechazo severo (5 por ciento)Desarrollaron enfermedad. (AU)