Estimated glomerular filtration rate in clinical practice: Consensus positioning of the Brazilian Society of Nephrology (SBN) and Brazilian Society of Clinical Pathology and Laboratory Medicine (SBPC/ML) / Estimativa da taxa de filtração glomerular na prática clínica: posicionamento consensual da Sociedade Brasileira de Nefrologia (SBN) e Sociedade Brasileira de Patologia Clínica e Medicina Laboratorial (SBPC/ML)

ABSTRACT Chronic kidney disease (CKD) represents one of today's main public health problems. Serum creatinine measurement and estimation of the glomerular filtration rate (GFR) are the main tools for evaluating renal function. There are several equations to estimate GFR, and CKD-EPI equation (Chronic Kidney Disease - Epidemiology) is the most recommended one. There are still some controversies regarding serum creatinine measurement and GFR estimation, since several factors can interfere in this process. An important recent change was the removal of the correction for race from the equations for estimating GFR, which overestimated kidney function, and consequently delayed the implementation of treatments such as dialysis and kidney transplantation. In this consensus document from the Brazilian Societies of Nephrology and Clinical Pathology and Laboratory Medicine, the main concepts related to the assessment of renal function are reviewed, as well as possible existing controversies and recommendations for estimating GFR in clinical practice.

RESUMO A doença renal crônica (DRC) representa um dos principais problemas de saúde pública da atualidade. A dosagem da creatinina sérica e a estimativa da taxa de filtração glomerular (TFG) são as principais ferramentas para avaliação da função renal. Para a estimativa da TFG, existem diversas equações, sendo a mais recomendada a CKD-EPI (Chronic Kidney Disease - Epidemiology). Existem ainda algumas controvérsias com relação à dosagem da creatinina sérica e da estimativa da TFG, uma vez que vários fatores podem interferir nesse processo. Uma importante mudança recente foi a retirada da correção por raça das equações para estimativa da TFG, que superestimavam a função renal, e consequentemente retardavam a implementação de tratamentos como diálise e transplante renal. Neste documento de consenso da Sociedade Brasileira de Nefrologia e Sociedade Brasileira de Patologia Clínica e Medicina Laboratorial são revisados os principais conceitos relacionados à avaliação da função renal, possíveis controvérsias existentes e recomendações para a estimativa da TFG na prática clínica.

Estimated glomerular filtration rate in clinical practice: Consensus positioning of the Brazilian Society of Nephrology (SBN) and Brazilian Society of Clinical Pathology and Laboratory Medicine (SBPC/ML).

Chronic kidney disease (CKD) represents one of today's main public health problems. Serum creatinine measurement and estimation of the glomerular filtration rate (GFR) are the main tools for evaluating renal function. There are several equations to estimate GFR, and CKD-EPI equation (Chronic Kidney Disease - Epidemiology) is the most recommended one. There are still some controversies regarding serum creatinine measurement and GFR estimation, since several factors can interfere in this process. An important recent change was the removal of the correction for race from the equations for estimating GFR, which overestimated kidney function, and consequently delayed the implementation of treatments such as dialysis and kidney transplantation. In this consensus document from the Brazilian Societies of Nephrology and Clinical Pathology and Laboratory Medicine, the main concepts related to the assessment of renal function are reviewed, as well as possible existing controversies and recommendations for estimating GFR in clinical practice.

Consecutive Spontaneous Triplet and Twin Pregnancies in a Woman After Renal Transplantation.

BACKGROUND: There are numerous reports of successful pregnancies following kidney transplantation. However, little information is available regarding the management and evolution of multiple pregnancies in a kidney-transplanted woman. CASE REPORT: We report the case of successful consecutive spontaneous triplet and twin pregnancies in a woman who had undergone kidney transplantation at 30 years of age, 12 years before the first pregnancy, as a result of end-stage renal disease secondary to chronic glomerulonephritis due to diffuse proliferative lupus nephritis. An integrated multidisciplinary team closely followed progress during the pregnancies. Maternal complications during the pregnancies included light proteinuria, controlled hypertension, and anemia. No graft rejection episodes or deterioration of renal function was noted during the pregnancies or after the deliveries. CONCLUSION: Currently, more than 2 years after her last pregnancy, the mother and all 5 babies are healthy and the mother's renal transplant function is normal.

Água e a saúde do rim transplantado / Water and health of the transplanted kidney

Pacientes transplantados de rim apresentam grande volume de diurese e um risco maior de desidratação e de comprometimento do bom funcionamento do novo rim. Devem ser orientados ativamente para uma ingestão maior de líquidos, especialmente de água. Um estado de "sub-hidratação" poderia ter implicações no bom funcionamento do rim e na progressão de disfunção crônica do enxerto renal. A resposta à questão clássica de "quanto de água se deve beber por dia?" ainda permanece controversa, mas aparentemente o volume é maior do que aquele recomendado como "beber se tiver sede e na quantidade que mate a sede"...

Vitamin D deficiency and insufficiency in patients with chronic kidney disease.

INTRODUCTION: Vitamin D deficiency is common among patients with chronic kidney disease (CKD). A higher level of serum vitamin D is expected in residents of the tropics in relation to inhabitants of non-tropical regions, due to greater sun exposure and increased production of vitamin D. OBJECTIVE: To analyze serum levels of vitamin D, such as 25-hydroxyvitamin D - 25(OH)D, in Brazilian patients at the predialytic stage with CKD. METHODS: We studied 125 patients (aged 57.4 ± 16.2 years, 78 were white and 55.2%, male), with creatinine 2.67 ± 1.73 mg/dL and creatinine clearance 43.7 ± 34.5 mL/min. Body mass index was 27.4 ± 4.7 kg/m², and waist circumference was 95.0 ± 14.0 cm. Calcium was 9.3 ± 0.6 mg/dL, intact parathormone (iPTH) 212.6 ± 221.2 pg/mL and serum albumin 4.2 ± 0.6 g/dL. The mean 25(OH)D was 23.9 ± 10.7 ng/mL. RESULTS: Out of the 125 patients, we found that 92 (72.6%) had suboptimal levels of 25(OH)D < 30 ng/mL, and 65 (52%) had vitamin D insufficiency (15-29 ng/mL); 27 (21.5%) had deficiency (5-14 ng/mL) and only one patient had severe vitamin D deficiency <5 ng/mL. No differences were observed among the levels of 25 (H)D in stratified patients as to the CKD stage. Levels of 25(OH)D were higher among males (38.1 ± 20.6 versus 22.4 ± 9.7 ng/mL; p < 0.0001), and there was an inverse correlation between levels 25(OH)D and iPTH, proteinuria and abdominal circumference, and a positive correlation between 25(OH)D and calcium and serum albumin. Multivariate analysis only showed inverse correlation between serum 25(OH)D and iPTH and abdominal circumference. CONCLUSION: Even though the Brazilian population live in a tropical region, most patients had suboptimal levels of serum vitamin D, and this pattern may play a role in the development of hyperparathyroidism.

Insuficiência e deficiência de vitamina D em pacientes portadores de doença renal crônica / Vitamin D deficiency and insufficiency in patients with chronic kidney disease

INTRODUÇÃO: Hipovitaminose D é bem documentada em pacientes portadores de doença renal crônica (DRC). Espera-se níveis inferiores em habitantes de regiões não tropicais em relação aos habitantes de regiões tropicais, pela inferição de uma maior exposição solar e maior produção de vitamina D. OBJETIVO: Analisar os níveis séricos de vitamina D, como 25-hidroxivitamina D - 25(OH)D, de 125 pacientes brasileiros portadores de DRC em fase pré-dialítica. MÉTODOS: Foram estudados 125 pacientes (57,4 ± 16,2 anos, 78 brancos e 55,2% homens), com creatinina de 2,67 ± 1,73 mg/dL e o clearance estimado 43,7 ± 34,5 mL/min. O índice de massa corporal era de 27,4 ± 4,7 kg/m² e a circunferência abdominal de 95,0 ± 14,0 cm. O cálcio era de 9,3 ± 0,6 mg/dL, o paratormônio intacto (PTHi) 212,6 ± 221,2 pg/mL e a albumina sérica 4,2 ± 0,6 g/dL. A média de 25(OH)D era de 23,9 ± 10,7 ng/mL. RESULTADOS: Dos 125 pacientes, 92 (72,6%) apresentavam níveis de 25(OH)D < 30 ng/mL, sendo que 65 (52%) apresentavam insuficiência (15-29 ng/mL); 27 (21,5%) apresentavam deficiência (5-14 ng/mL) e apenas um paciente apresentava deficiência severa < 5 ng/mL. Não foram observadas diferenças entre os níveis de 25(OH)D nos pacientes estratificados quanto ao estágio de DRC. Os níveis de 25(OH)D foram maiores nos homens (38,1 ± 20,6 versus 22,4 ± 9,7 ng/ml; p < 0,0001), havendo também uma correlação inversa entre os níveis de 25(OH)D e de PTHi, proteinúria e circunferência abdominal, e uma correlação positiva entre 25(OH)D e cálcio total e albumina sérica. Na análise multivariada, encontrou-se apenas correlação inversa entre 25(OH)D e circunferência abdominal e PTHi. CONCLUSÃO: A despeito de a população do Brasil estar em um clima tropical, a maioria dos pacientes analisados apresentou níveis séricos subótimos de vitamina D, podendo este achado estar relacionado ao desenvolvimento de hiperparatireoidismo.

INTRODUCTION: Vitamin D deficiency is common among patients with chronic kidney disease (CKD). A higher level of serum vitamin D is expected in residents of the tropics in relation to inhabitants of non-tropical regions, due to greater sun exposure and increased production of vitamin D. OBJECTIVE: To analyze serum levels of vitamin D, such as 25-hydroxyvitamin D - 25(OH)D, in Brazilian patients at the predialytic stage with CKD. METHODS: We studied 125 patients (aged 57.4 ± 16.2 years, 78 were white and 55.2%, male), with creatinine 2.67 ± 1.73 mg/dL and creatinine clearance 43.7 ± 34.5 mL/min. Body mass index was 27.4 ± 4.7 kg/m², and waist circumference was 95.0 ± 14.0 cm. Calcium was 9.3 ± 0.6 mg/dL, intact parathormone (iPTH) 212.6 ± 221.2 pg/mL and serum albumin 4.2 ± 0.6 g/dL. The mean 25(OH)D was 23.9 ± 10.7 ng/mL. RESULTS: Out of the 125 patients, we found that 92 (72.6%) had suboptimal levels of 25(OH)D < 30 ng/mL, and 65 (52%) had vitamin D insufficiency (15-29 ng/mL); 27 (21.5%) had deficiency (5-14 ng/mL) and only one patient had severe vitamin D deficiency <5 ng/mL. No differences were observed among the levels of 25 (H)D in stratified patients as to the CKD stage. Levels of 25(OH)D were higher among males (38.1 ± 20.6 versus 22.4 ± 9.7 ng/mL; p < 0.0001), and there was an inverse correlation between levels 25(OH)D and iPTH, proteinuria and abdominal circumference, and a positive correlation between 25(OH)D and calcium and serum albumin. Multivariate analysis only showed inverse correlation between serum 25(OH)D and iPTH and abdominal circumference. CONCLUSION: Even though the Brazilian population live in a tropical region, most patients had suboptimal levels of serum vitamin D, and this pattern may play a role in the development of hyperparathyroidism.

[Nephrogenic systemic fibrosis: a severe complication of use to gadolinium in patients with kidney failure]. / Fibrose sistêmica nefrogênica: uma complicação grave do uso do gadolínio em pacientes com insuficiência renal.

Nephrogenic systemic fibrosis (NSF), also known as nephrogenic fibrosing dermopathy (NFD), is a condition that has occurred only in patients with renal insufficiency. Besides lesions of the skin, this syndrome include fibrosis of skeletal muscle, joints, liver, lung, and heart, with possible fatal outcomes. This disease was first described in 1997 and several reports described the development of NSF after the exposure to gadolinium-based magnetic resonance imaging contrast agents. This review aims to alert physicians and nephrologists about this new pathology that affects patients with renal dysfunction, describing its demographic and epidemiologics aspects, clinic presentation, diagnosis and prognosis, beyond options to prevent and current treatment. We concluded that in all patient with elevated serum creatinine physicians should estimade his kidney function (creatinine clearence) in order to safety of magnetic resonance.

Fibrose sistêmica nefrogênica: uma complicação grave do uso do gadolínio em pacientes com insuficiência renal / Nephrogenic systemic fibrosis: a severe complication of use to gadolinium in patients with kidney failure

Fibrose sistêmica nefrogênica (FSN), também conhecida como dermopatia fibrosante nefrogênica (DFN), é uma condição que ocorre apenas em pacientes com disfunção renal. Além das lesões cutâneas, esta síndrome inclui fibrose de músculo esquelético, articulações, fígado, pulmão e coração e pode ser fatal. Esta doença foi primeiramente descrita em 1997 e vários estudos descrevem a relação etiológica da FSN com a exposição a agentes de contraste contendo gadolínio, usado em exames de ressonância magnética. Esta revisão tem como objetivo alertar médicos clínicos e nefrologistas sobre essa nova patologia que acomete pacientes com alteração da função renal, demonstrando aspectos demográficos e epidemiológicos, apresentação clínica, diagnóstico e prognóstico além das opções de prevenção e terapêuticas atuais. Concluímos que todo paciente apresentando creatinina sérica elevada deve ter sua função renal (clearance de creatinina) estimada, visando a segurança na realização da ressonância magnética.

Nephrogenic systemic fibrosis (NSF), also known as nephrogenic fibrosing dermopathy (NFD), is a condition that has occurred only in patients with renal insufficiency. Besides lesions of the skin, this syndrome include fibrosis of skeletal muscle, joints, liver, lung, and heart, with possible fatal outcomes. This disease was first described in 1997 and several reports described the development of NSF after the exposure to gadolinium-based magnetic resonance imaging contrast agents. This review aims to alert physicians and nephrologists about this new pathology that affects patients with renal dysfunction, describing its demographic and epidemiologics aspects, clinic presentation, diagnosis and prognosis, beyond options to prevent and current treatment. We concluded that in all patient with elevated serum creatinine physicians should estimade his kidney function (creatinine clearence) in order to safety of magnetic resonance.

Resultados do censo de diálise da SBN, 2007 / Dialysis census results - 2007 from the Brazilian Society of Nephrology

Introdução: Apresentamos dados do censo da SBN sobre os pacientes em programa de diálise crônica em janeiro de 2007. Métodos: Estudotransversal nacional, utilizando questionário preenchido por responsáveis pelas unidades de diálise do Brasil cadastradas na SBN. Resultados: Dasunidades consultadas, 546 (87,9%) responderam ao censo. Os dados nacionais foram estimados para a população global em diálise. O número totalde pacientes estimado em diálise foi de 73.605. O aumento do número absoluto de pacientes foi de 3,9% no último ano. As taxas de prevalência e deincidência de tratamento dialítico foram de 391 e 181 pacientes por milhão da população. O número estimado de pacientes que iniciaram tratamentoem 2006 foi de 34.710. A taxa anual de mortalidade bruta foi de 14,3%. Em relação aos pacientes prevalentes, 25,5% tinham idade ≥ 65 anos, 91%estavam em hemodiálise e 9% em diálise peritoneal, 32.650 (44%) estavam em fila de espera para transplante, 26% eram diabéticos, 9,4% dospacientes em hemodiálise usavam cateter venoso central, 34% dos pacientes tinham fósforo sérico > 5,5mg/dL e 38% hemoglobina <11g/dL.Discussão/Conclusões: Esses dados destacam a importância do censo anual para o planejamento da assistência e indicam áreas que necessitamser melhoradas.

Introduction: We report data of the annual survey of the Brazilian Society of Nephrology about chronic renal failure patients undergoing dialysis inJanuary 2007. Methods: Cross-sectional study using a questionnaire filled out by responsibles for all dialysis units in the country accredited by theBrazilian Society of Nephrology. Results: 546 (87.9%) of the dialysis units in the country answered the questionnaire. National data were estimatedfor the overall dialysis population. The total estimated number of patients on dialysis was 73,605. The absolute increase in patient number was 3.9%from Jan. 2006 to 2007. Prevalence and incidence rates of dialysis treatment were 391 and 181 patients per million population, respectively. Theestimated number of new patients starting dialysis program in 2006 was 34,710. The annual gross mortality rate was 14.3%. For prevalent dialysispatients, 25.5% were aged 65 years or older, 91% were on hemodialysis and 9% on peritoneal dialysis, 32,650 (44%) were on a waiting list of renaltransplant, 26% were diabetics, 9.4% of the hemodialysis patients used a central venous catheter as dialysis access, 34% had serum phosphorus >5.5 mg/dl and 38% hemoglobin <11 g/dl. Discussion/Conclusions: These data highlight the importance of the census for health care planning andindicate areas that need improvement.

Perfil dos pacientes encaminhados à terapia renal substitutiva de umambulatório de nefrologia pertencente a um hospital terciário / Profile of patients with end-stage renal disease before starting renalreplacement therapy, derived from a tertiary nephrology center

ambulatório de nefrologia de um hospital terciário. Materiais e métodos: Foram analisados retrospectivamente dados epidemiológicos, clínicos elaboratoriais de 246 pacientes com DRC encaminhados para TRS entre janeiro de 2004 e janeiro de 2006. Resultados: 50,6% eram homens, com54,5±15,5 anos de idade e tempo médio de acompanhamento de 24,8+34,5 meses. As principais causas de DRC foram: diabetes (DM-32,9%), hipertensãoarterial (HAS-25,2%) e glomerulonefrite crônica (GNC-13%). Apenas 20,6% apresentavam fistula artério-venosa (FAV) funcionante. Apenas três pacientes(1,2%) foram encaminhados a programa de diálise peritoneal (DP). Os homens tiveram chance 2,3 vezes maior de ter FAV confeccionada em relação àsmulheres (p=0,012 IC 1,2-4,4). Nos pacientes com mais de 12 meses de acompanhamento, havia chance 4,6 vezes maior para a presença de FAV(p=<0,0001 e IC 2,1-10,0). A doença com maior prevalência de FAV confeccionada foi doença renal policística (31,8%) e a com menor, DM (13,4%). Ospacientes diabéticos apresentaram risco 2,3 vezes maior de ter tempo de seguimento ambulatorial inferior a 12 meses (p=0,0027 e IC 1,3-3,9) e risco de2,3 vezes maior de não ter FAV confeccionada (p=0,029 e IC 1,1-4,9). Conclusão: Os dados analisados assemelham-se à estatística norte-americana emrelação ao DM como causa principal de DRC. O baixo encaminhamento para DP sugere dificuldade do sistema para absorver pacientes nesta modalidadee/ou tendência preferencial de encaminhamento para hemodiálise. Dificuldades locais concernentes à confecção de FAV refletem-se na baixa prevalênciade acessos funcionantes por ocasião do encaminhamento (20,6%), principalmente quando o tempo de seguimento é inferior a 12 meses, o sexo é ofeminino e a doença de base é DM.

Objectives: to analyze the profile of chronic kidney disease (CKD) patients before starting renal replacement therapy (RRT), from a tertiary nephrologycenter. Materials and Methods: we analyzed retrospectively, epidemiologic, clinical and laboratory data from 246 CKD patients assigned to RRT, fromJanuary 2004 to January 2006. Results: In this study, 50.6% were male. The main etiologies of CKD were: diabetes (DM-32.9%), hypertension (HTN-25.2%), and chronic glomerulonephritis (CGN-13%). The median age and follow-up time were 54.5+15.5 years and 24.8+34.5 months, respectively. Only20.6% patients had a patent arteriovenous fistula (AVF). Only 3 patients were assigned to a peritoneal dialysis program (PDP). After analysis, men had 2.3times greater chance of AVF through vascular access, than women (p=0.012, CI 1.2-4.4). However, for those with more than 12 months of follow-up, ahigher probability (4.6 times) of AVF was detected (p<0.0001, CI 2.1-10.0). PKD patients had the best scores for AVF placements (31.8%) and patients withdiabetes revealed the worst scores (13.4%). CGN presented the longest ambulatory follow-up time before starting RRT, whereas obstructive nephropathypresented the smallest. There was no difference between gender distribution and creatinine clearance in patients with and without diabetes. However,diabetic patients were 2.3 times more prone to have a follow-up time less than 12 months (p=0.0027, CI 1.3-3.9) and 2.3 times less prone to have anaccessible AVF (p=0.029, CI 1.1-4.9). Conclusions: The analyzed data in this tertiary hospital are in tandem with the North-American statistics, which referto diabetes as the main cause of CKD. The low number of patients assigned to a PDP suggests that the structure and organization of peritoneal dialysisfacilities cannot meet the demand and also suggests a preference towards hemodialysis as the mode of choice for RRT...

Qualidade de vida de pacientes com insuficiência renal crônica terminal em hemodiálise de alta eficiência / Quality of life in patients with chronic renal failure under high-efficiency hemodialysis

Este estudo teve como objetivo avaliar a qualidade de vida (QV) de pacientes com insuficiência renal crônica em hemodiálise de alta eficiência, através do questionário Medical Outcomes Study 36 Item Short Form Health Survey (SF36) correlacionar seus escores aos dados sociodemográficos, clínicos, laboratoriais, Escala de Karnofsky e Índice Cognitivo de Depressão (ICD). Estudamos 50 pacientes com idade média 37 anos, tempo médio de tratamento 50,6 meses e observamos alteração da QV evidenciada por correlações entre escores do SF36 e aspectos sociodemográficos, clínicos, Escala de Karnofsky e ICD. O estudo permitiu concluir que o uso isolado do SF36 pode subsidiar a avaliação da conduta terapêutica.