ABSTRACT
La aldosterona, sintetizada en la zona glomerulosa de la corteza suprarrenal, es la principal hormona reguladora del metabolismo de sodio y potasio y del volumen extracelular. A través del receptor de mineralocorticoides, actúa como la señal endocrina final del sistema renina-angiotensina-aldosterona sobre el epitelio del túbulo renal y del colon distal, que estimula la reabsorción de sodio y la secreción de potasio. El agua se reabsorbe, vía ósmosis, favoreciendo la expansión del volumen circulante y, por ende, incrementando la presión arterial. Recientemente, se ha centrado el interés en las acciones no clásicas de la aldosterona sobre el endotelio vascular, corazón y riñón. Existe evidencia de que la aldosterona está involucrada en la remodelación vascular, la función endotelial y la formación de colágena, y que contribuye a la progresión de la insuficiencia cardiaca, así como del daño renal. Se revisa la evidencia clínica y experimental que fundamenta el uso de bloqueadores de aldosterona para detener la progresión del daño renal en diferentes modelos.
Aldosterone is synthesized in the adrenal cortex and is the main regulator of sodium and potassium metabolism and the extracellular volume. Acting through the mineralocorticoid receptor, it is the final endocrine signal of the renin-angiotensin-aldosterone system with effects on the renal tubular epithelium and distal colon stimulating sodium reabsorption and potassium secretion. Water is absorbed by osmosis favoring expansion of circulating volume and increasing arterial blood pressure. Recently there has been great interest in the non-classical actions of aldosterone on the vascular endothelium, heart and kidney. There is evidence suggesting that aldosterone participates in vascular remodeling, endothelial function and collagen deposition, contributing to heart failure progression and kidney damage. Clinical and experimental evidence supporting the use of aldosterone blocking agents in different models of kidney damage is reviewed.
ABSTRACT
La nefropatía crónica del trasplante (NCT) se caracteriza por fibrosis intersticial y atrofia tubular, pero su etiología es diversa. El objetivo del trabajo fue evaluar el seguimiento cualitativo de proteínas urinarias en pacientes con más de seis años de trasplante renal y compararlo con parámetros de laboratorio y con biopsia renal. Se evaluaron 17 pacientes durante un año, a través de creatinina sérica, proteinuria y fraccionamiento proteico por electroforesis en geles de poliacrilamida (SDS-PAGE) en una y dos dimensiones con coloración argéntica. Todos los pacientes con biopsias características de nefropatía crónica del trasplante presentaron un perfil tubular y aquellos con glomerulopatía del trasplante evidenciaron un perfil predominantemente glomerular. Los cambios en el perfil tubular se asociaron a infecciones urinarias, pulmonares e intestinales y a una respuesta inmunológica en el límite al rechazo (borderline), aún sin modificaciones evidentes en la creatinina sérica ni en la proteinuria. La electroforesis bidimensional permitió detectar claramente las proteínas orosomucoide y zinc alfa-2 glicoproteína, aparentemente asociadas a hialinosis arteriolar por toxicidad causada por ciclosporina. La electroforesis SDS-PAGE permitió identificar el sitio de lesión en el nefrón y cambios en la evolución, aún en presencia de vestigios de proteinuria. Las electroforesis SDS-PAGE mono y bidimensional se plantean como complemento para la evaluación de la condición clínica del paciente trasplantado renal crónico.
Post-transplant chronic nephropathy is characterized by interstitial fibrosis and tubular atrophy. These alterations are non-specific, but the glomerular and vascular lesions help to differentiate the etiological causes. The aim of this study was to determine the qualitative follow-up study of urine proteins in patients, six years after receiving a renal transplant, and compare their relationship to laboratory parameters and renal biopsy. The evolution of 17 patients with renal transplant was studied for one year, through serum creatinine, proteinuria, and polyacrylamide gel electrophoresis in the presence of sodium dodecylsulfate (SDS-PAGE) in one and two dimensions with silver staining. The patients with chronic nephropathy by renal biopsy presented a tubular profile of urinary proteins, and those who presented glomerulopathy showed a predominant glomerular profile. Changes in the tubular profiles during the follow-up study were associated to urinary tract, pulmonary, and intestinal infections, as well as borderline rejection, even without evident changes in either proteinuria or serum creatinine. The bidimensional electrophoresis clearly marked the orosomucoid proteins and zinc alpha-2 glycoprotein, generally associated to arterial hyalinosis due to ciclosporin toxicity. Even with traces of proteinuria, SDS-PAGE with silver staining made it possible to identify the renal lesion location. It also enabled the detection of the stable profiles of urinary proteins and changes in the evolution, without modification of serum creatinine. SDS-PAGE in one and two dimensions is used as a complement in the evaluation of renal transplant patients' clinical condition.
Subject(s)
Kidney Transplantation , Electrophoresis , Electrophoresis, Polyacrylamide Gel , Renal Insufficiency, Chronic , Urine , Cyclosporine , Hyaline Fibromatosis SyndromeABSTRACT
La enfermedad renal crónica (ERC) es un grave problema de salud pública. Se espera que el número de personas con insuficiencia renal que reciben tratamiento con diálisis y trasplante aumente dramáticamente en los próximos años. Los malos resultados de la ERC no se limitan a la insuficiencia renal terminal, sino que también incluyen a las complicaciones derivadas de una menor función renal, como hipertensión arterial, anemia, desnutrición, trastornos óseos y minerales, neuropatía, así como un mayor riesgo de enfermedad cardiovascular. El diagnóstico precoz basado en la presencia de proteinuria o una velocidad de filtración glomerular estimada reducida, puede permitir la intervención temprana para reducir: el riesgo de insuficiencia renal progresiva, los eventos cardiovasculares y la mortalidad que se asocian con la ERC. Las estrategias eficaces para frenar la progresión de la ERC y reducir el riesgo cardiovascular están disponibles en la actualidad. Los modelos clínicos de atención que faciliten la entrega de los aspectos diversos y complejos del tratamiento en forma simultánea, podrían mejorar la gestión y probablemente los resultados clínicos
Chronic kidney disease (CKD) is a serious public health problem. The number of persons with kidney failure who are treated with dialysis and transplantation is expected to rise dramatically in the coming years. The poor outcomes of CKD are not restricted to kidney failure but also include the complications of decreased kidney function, such as hypertension, anemia, malnutrition, bone and mineral disorders and neuropathy, as well as increased risk of cardiovascular disease. Early diagnosis on the basis of presence of proteinuria or reduced estimated glomerular filtration rate could permit early intervention to reduce the risk of: kidney failure, cardiovascular events and death that are associated with CKD. Effective strategies are available to slow the progression of CKD and reduce cardiovascular risk. Clinical models of care that facilitate delivery of the many complex aspects of treatment simultaneously could enhance management and probably the clinical outcomes
Subject(s)
Humans , Renal Insufficiency, Chronic/diagnosis , Renal Insufficiency, Chronic/prevention & control , Proteinuria , Cardiovascular Diseases/prevention & control , Risk Factors , Early Diagnosis , Diabetes Complications , Albuminuria , Renal Insufficiency, Chronic/complications , Glomerular Filtration Rate , Hypertension/complications , Hypertension/drug therapy , Antihypertensive Agents/therapeutic useABSTRACT
A caquexia tem sido relacionada à maior mortalidade de pacientes com doença renal crônica, tanto em humanos, como em animais. O escore de condição corporal (ECC) pode ser utilizado em conjunto com o peso para melhor avaliação da composição corporal desses animais. O objetivo deste trabalho foi de correlacionar o escore de condição corporal com o prognóstico de felinos com doença renal crônica. Avaliaram-se 110 felinos idosos, dos quais 70 apresentavam-se hígidos (Grupo I) e 40 apresentavam doença renal crônica (Grupo II). No grupo I, apenas 5,7 por cento dos gatos apresentaram ECC abaixo do ideal e destes nenhum foi classificado como caquético. No grupo II, 70 por cento dos gatos apresentaram ECC abaixo do ideal, dos quais 32,5 por cento eram caquéticos. A taxa de mortalidade no grupo II foi significantemente maior naqueles caquéticos. O ECC abaixo do considerado ideal indica um prognóstico desfavorável nos pacientes com doença renal crônica.
Cachexia has been associated with higher mortality in patients with chronic renal disease both in human and veterinary medicine. Body condition score (BCS) can be used along with body weight for a better evaluation of a patient's body composition. The objective of this study was to associate body condition score with prognosis of cats with chronic renal disease. One hundred and ten elderly cats were evaluated; of which 70 were healthy (Group I) and 40 had been diagnosed with chronic renal disease (Group II). In Group I, only 5.7 percent of the cats presented a BCS below ideal, though none were found to be cachectic. In Group II, 70 percent of the cats presented a BCS below ideal, where 32.5 percent were cachectic. Mortality was significantly higher within the cachectic patients of Group II. BCS below ideal indicates a poor prognosis for patients with chronic renal disease.
ABSTRACT
Lithium is a drug widely used in clinical psychiatry, often as first-line treatment. However, it has generated much controversy because of the likely adverse effects of both acute and chronic use, mainly in the kidney. With respect to prolonged exposure to lithium, it would be detrimental to the kidneys at variable extent, depending on factors such as duration of treatment, dosage of drug, patient age, renal damage, prior comorbidities, among others not yet sufficiently elucidated. The principal mechanism of renal function changes was determined by morphological changes, such as interstitial nephritis, interstitial-medullar fibrosis and tubular atrophy, all irreversible phenomena that ultimately lead to a tubuloglomerular imbalance and commitment of the GFR. Other aspects of chronic nephropathy induced by lithium and their production mechanisms are being studied, also the search and advanced diagnostic techniques to predict and / or detect early changes. Among them have described the pathology (renal biopsy), although this form of diagnosis is very late. Thus it seeks the introduction of imaging and serological markers of kidney failure as tools that provide information about kidney condition earlier.
El Litio es un fármaco ampliamente utilizado en psiquiatría, muchas veces como tratamiento de primera línea. Existe en la actualidad una activa controversia acerca de sus probables efectos adversos a nivel renal, tanto agudos como crónicos, ya que la exposición prolongada al Litio sería deletérea para el riñón en una magnitud variable, dependiendo de factores como duración del tratamiento, dosis del fármaco, edad del paciente, daño renal previo y comorbilidad, entre otros aún no suficientemente dilucidados. El origen del mecanismo principal de alteración de la función renal estaría en alteraciones morfológicas como la Nefritis Intersticial, la Fibrosis Intersticio-Medular y la Atrofia Tubular, todos fenómenos irreversibles que finalmente conducirían a un desbalance tubuloglomerular y a un compromiso de la VFG. Otros aspectos de la Neuropatía Crónica inducida por Litio y de sus mecanismos de producción se encuentran en estudio, así como también la búsqueda y perfeccionamiento de técnicas diagnósticas que permitan predeciry/o detectar tempranamente los cambios mencionados. Entre estas últimas se ha descrito la anatomía patológica (biopsia renal), aunque esta es una forma de diagnóstico muy tardía. Es por ello que se busca la introducción de la imagenología y de marcadores serológicos de falla renal como herramientas que entreguen información sobre la condición del riñón más precozmente.
Subject(s)
Humans , Kidney Failure, Chronic , Lithium , Lithium/adverse effectsABSTRACT
O transplante renal alcançou expressivos e crescentes índices de sucesso desde sua implantação, constituindo atualmente uma terapia substitutiva de larga escala. É cada vez mais freqüente o encontro de biópsias de enxerto renal na rotina dos laboratórios de patologia, cujos achados são os mais variados. Este artigo resulta da experiência dos membros do Clube do Rim (da Sociedade Brasileira de Patologia) e apresenta um panorama geral da patologia do transplante renal, enfatizando a atual classificação de Banff, com suas principais categorias e entidades de diagnóstico problemático.
Renal transplant has reached remarkable and growing rates of success since its introduction; nowadays it is a widely used replacement therapy. Renal allograft biopsies are increasingly more frequent in the routine of pathology laboratories, whose histological findings are varied. This paper results from the expertise of the members of the Kidney Club of Sociedade Brasileira de Patologia, and presents a general overview of renal allograft pathology, focusing on the current Banff classification, its main categories and cases of difficult diagnosis.