The EKiTE network (epidemiology in kidney transplantation - a European validated database): an initiative epidemiological and translational European collaborative research.

BACKGROUND: Kidney transplantation is considered to be the treatment of choice for people with end-stage renal disease (ESRD). However, due to the shortage of available organs and the increase in the ESRD prevalence in Europe, it is essential to improve transplantation outcomes by studying the related prognostic factors. Today, there is no European registry collecting data to perform such clinical epidemiology studies. MAIN BODY: Entitled EKiTE, for European cohort for Kidney Transplantation Epidemiology, this prospective and multicentric cohort includes patients from Spanish (Barcelona), Belgian (Leuven), Norwegian (Oslo) and French (Paris Necker, Lyon, Nantes, Nancy, Montpellier, Nice and Paris Saint Louis) transplantation centers and currently contains 13,394 adult recipients of kidney (only) transplantation from 2005 and updated annually. A large set of parameters collected from transplantation until graft failure or death with numbers of post-transplantation outcomes. The long-term follow-up and the collected data enable a wide range of possible survival and longitudinal analyses. CONCLUSION: EKiTE is a multicentric cohort aiming to better assess the natural history of the ESRD in European kidney transplant recipients and perform benchmarking of clinical practices. The data are available for clinical epidemiology studies and open for external investigators upon request to the scientific council. Short-term perspectives are to extend EKITE network to other European countries and collect additional parameters in respect of the common thesaurus.

[Systemic AA amyloidosis induced by benign neoplasms]. / Amiloidosis secundaria (AA) asociada a tumoraciones benignas.

Amyloidosis is a systemic disorder characterized by the extracellular tissue deposition of insoluble, toxic aggregates in bundles of beta-sheet fibrillar proteins. These deposits are typically identified on the bases of their apple-green birrefringence under a polarized light microscope after staining with Congo red, and by the presence of rigid, nonbranching fibrils 8 to 10 nm in diameter on electron microscopy. The type of amyloid fibril unit can be further defined by immunohistology or by immunoelectron microscopy. It has been described at least 25 different human protein precursors of amyloid fibrils, which will describe its corresponding amyloid disease. The most common types of amyloidosis are AL (primary) and AA (secondary) types; the former, is the most frequent and is due to deposition of proteins derived from immunoglobulin light chain fragments, occurring alone or in association with multiple myeloma. The later (AA), is caused by deposition of fibrils composed of fragments of the acute phase reactant serum amyloid A (SAA) and complicates chronic diseases with ongoing or recurring inflammation, namely; rheumatoid arthritis (RA), juvenile chronic polyarthritis, ankylosing spondylitis, familial periodic fever syndromes (Familial Mediterranean Fever), chronic infections and furthermore, some neoplasms (mainly renal cell carcinoma and Hodgkin's disease). Despite its less frequent association, some benign neoplasms can subsequently complicate to AA amyloidosis, therefore, an early diagnose and successful treatment may lead indeed, to regression of the amyloid disease. Herein, we present two cases of AA amyloidosis, both of them caused by 2 different benign neoplasms: 1. A 34 year-old woman, after chronic oral contraceptive use, developed an hepatic adenoma (fig. 1) which finally lead to AA amyloidosis with primary kidney presentation (pure nephrotic syndrome) (table 1). Post-surgical complications yield to acute renal failure from which unfortunately could not be recovered. After being on hemodialysis therapy during 10 months she received a first renal allograft without any complication. 2. A 20 year old woman, was diagnosed of AA amyloidosis after a renal biopsy (fig. 2) because of nephrotic syndrome (table 1). Further investigation lead to the finding of a hialyne-vascular type Castleman's disease located in the retroperitoneum (fig. 2). Despite surgical resection and medical treatment (colchicine) she developed progressive renal failure requiring initialization of hemodialysis therapy. After 6 years being on hemodialysis, she received a first renal allograft which is currently functioning after one year of follow- up. Although other chronic inflammatory diseases complicate more frequently to AA amyloidosis, benign tumors have to be taken into account as a potential ethiological cause for secondary amyloidosis.

Amiloidosis secundaria (AA) asociada a tumoraciones benignas / Systemic AA amyloidosis induced by benign neoplasms

La amiloidosis se caracteriza por el depósito de proteínas de características ultraestructurales fibrilares, con plegamiento Beta en capas e insolubles, que se depositan mayoritariamente a nivel de los espacios extracelulares de órganos y tejidos. Se clasifica típicamente según la naturaleza bioquímica de la proteína fibrilar, y según su distribución en el organismo podrá ser sistémica o localizada. La amiloidosis sistémica más frecuente en la práctica clínica es la denominada AL (idiopática primaria o asociada a mieloma múltiple) cuyas fibrillas están formadas por cadenas ligeras. En cambio, la amiloidosis AA (secundaria, reactiva o adquirida) es aquella que se desarrolla típicamente como complicación de una enfermedad inflamatoria crónica, destacando entre las más habituales; enfermedades de origen reumatológico (artritis reumatoide, espondilitis anquilopoyética, artritis psoriásica), la fiebre mediterránea familiar, la enfermedad inflamatoria intestinal, así como infecciones cronificadas (tuberculosis, osteomielitis). No obstante, otras causas responsables de su desarrollo y en muchas ocasiones infravaloradas, son las tumoraciones benignas. Algunas de estas entidades, también tendrán capacidad de actuar como estímulo responsable de la formación de estas proteínas, que finalmente se depositarán en diferentes tejidos del organismo. Es importante resaltar, que el diagnóstico precoz así como el tratamiento eficaz de la enfermedad subyacente ha permitido disminuir su incidencia, así como en algunos casos incluso revertirla. Aquí, presentamos dos casos clínicos paradigmáticos de tumoraciones benignas, adenoma hepático y Enfermedad de Castlemann, que desarrollaron posteriormente amiloidosis AA con afectación renal principalmente en forma de síndrome Nefrótico (AU)

Amyolidosis is a systemic disorder characterized by the extracellular tissue deposition of insoluble, toxic aggregates in bundles of Beta-sheet fibrillar proteins. These deposits are typically identified on the bases of their apple-green birrefringence under a polarized light microscope after staining with Congo red, and by the presence of rigid, non branching fibrils 8 to 10 nm in diameter on electron microscopy. The type of amyloid fibril unit can be further defined by immunohistology or by immunoelectron microscopy. It has been described at least 25 different human protein precursors of amyloid fibrils, which will describe its corresponding amyloid disease. The most common types of amyloidosis are AL (primary) and AA (secondary) types; the former, is the most frequent and is due to deposition of proteins derived from immunoglobulin light chain fragments, occurring alone or in association with multiple myeloma. The later (AA), is caused by deposition of fibrils composed of fragments of the acute phase reactant serum amyloid A (SAA) and complicates chronic diseases with ongoing or recurring inflammation, namely; rheumatoid arthritis (RA), juvenile chronic polyarthritis, ankylosing spondylitis, familial periodic fever syndromes (Familial Mediterranean Fever), chronic infections and furthermore, some neoplasms (mainly renal cell carcinoma and Hodking¿s disease). Despite its less frequent association, some benign neoplasms can subsequently complicate to AA amyloidosis, therefore, an early diagnose and successful treatment may lead indeed, to regression of the amyloid disease. Herein, we present two cases of AA amyloidosis, both of them caused by 2 different benign neoplasms: 1. A 34 year-old woman, after chronic oral contraceptive use, developed an hepatic adenoma (fig. 1) which finally lead to AA amyloidosis with primary kidney presentation (pure nephrotic syndrome) (table 1). Post-surgical complications yield to acute renal failure from which unfortunately could not be recovered. After being on hemodialysis therapy during 10 months she received a first renal allograft without any complication. 2. A 20 yearold woman, was diagnosed of AA amyloidosis after a renal biopsy (fig. 2) because of nephrotic syndrome (table 1). Further investigation lead to the finding of a hialyne-vascular type Castleman¿s disease located in the retroperotoneum (fig. 2). Despite surgical resection and medical treatment (colchicine) she developed progressive renal failure requiring initialization of hemodialysis therapy. After 6 years being on hemodialysis, she received a first renal allograft which is currently functioning after one year of follow- up. Although other chronic inflamatory diseases complicate more frequently to AA amyloidosis, benign tumors have to be taken into account as a potential ethiological cause for secondary amyloidosis (AU)