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.

[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.

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.

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.

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

This study aimed at assessing the quality of life (QL) of patients with chronic kidney failure under high efficiency hemodialysis. The Medical Outcomes Study 36 Item Short Form Health Survey (SF36) was applied, and the results were correlated with social-demographic profile, clinical and laboratorial data, Karnofsky's Scale and Depression Cognitive Index (DCI). The sample consisted of 50 patients with an average age of 37 and mean treatment duration of 50.6 months. LQ changes were evidenced by correlations of SF36 scores with social-demographic aspects, clinical data, Karnofsky's Scale, and DCI. It was concluded that the individual use of SF36 may aid the assessment of therapeutic conduct.

The relationship between ultrafiltrate volume with icodextrin and peritoneal transport pattern according to the peritoneal equilibration test.

OBJECTIVE: To establish a relationship between peritoneal transport membrane pattern, analyzed by the peritoneal equilibration test (PET), and drained volume using icodextrin (7.5% Ico) and glucose (3.86% Glu) solutions. DESIGN: Thirty peritoneal dialysis patients were submitted to a standard 4-hour PET and divided into 4 transport categories based on dialysate-to-plasma ratio of creatinine (D/Pcr) and dialysate ratio of glucose at 4 and zero hours of the dwell (D4/D0). Patients were asked to perform exchanges for 2 consecutive nights in 10-hour dwells (2 L 3.86% Glu solution on the first night, and 2 L 7.5% Ico solution on the second night). The drained volume was measured and dialysate samples from the overnight exchanges were obtained for beta2-microglobulin (B2M) levels. RESULTS: PET classification using D/Pcr showed that 46.6% of the patients were high and high-average transporters, or 23.3% when D4/D0 was used. In spite of this difference, both methods showed significant correlation (p = 0.0001, r = 0.862). The mean drained volumes were similar for both solutions (for 3.86% Glu, 2696 +/- 369 mL; for 7.5% Ico, 2654 +/- 424 mL). The high and high-average transport patients classified by D4/D0 achieved a higher ultrafiltration with 7.5% Ico than with 3.86% Glu (p = 0.0235). When classified by D/Pcr, the difference was not significant (p = 0.2243). In the low and low-average transport patients classified by D/Pcr, we observed a significantly lower ultrafiltration when 7.5% Ico was used compared to 3.86% Glu solution (p = 0.0197). Using D4/D0, we saw a tendency toward lower ultrafiltration (p = 0.0719) in the same group. We then correlated the PET results and the difference between drained volume with 7.5% Ico and 3.86% Glu solution [deltaV (I-G)]. We found a significant negative correlation between D4/D0 and deltaV (I-G) (p = 0.002, r = -0.5390), and a positive correlation between D/Pcr and deltaV (I-G) (p = 0.005, r = 0.4932). The levels of B2M obtained with 7.5% Ico were higher than those obtained with 3.86% Glu solution (for 7.5% Ico, 9.47 +/- 6.71 microg/vol; for 3.86% Glu, 7.29 +/- 4.91 microg/vol; p = 0.004). Furthermore, we found significant correlation between the total amount of B2M obtained with 7.5% Ico solution and D4/D0 (p < 0.0001, r = -0.4493), and D/Pcr (p < 0.0001, r = 0.5431). CONCLUSION: Mean drained volume was similar between the two solution groups. High transporters, as defined by D4/D0, achieved higher ultrafiltration with 7.5% Ico than with 3.86% Glu solution. This is most likely due to the higher number of small pores in the peritoneal membrane. Low transporters, as classified by D/Pcr, achieved lower ultrafiltration with 7.5% Ico than with 3.86% Glu solution. The deltaV (I-G) and the PET results showed significant correlation, confirming that high transporters have a higher ultrafiltration volume with 7.5% Ico. The total B2M mass obtained with 7.5% Ico was greater than with 3.86% Glu solution and significantly higher in the high transport patients, indicating a larger number of small pores. Thus, the deltaV (I-G) could give us an idea of the peritoneal transport pattern in peritoneal dialysis patients.

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.

High-efficiency short daily haemodialysis--morbidity and mortality rate in a long-term study.

BACKGROUND: In conventional haemodialysis (CHD), the morbidity and mortality rate is unacceptably high; consequently, variations in the length and frequency of the haemodialysis sessions have been studied to reduce the complications of dialysis treatment. In this sense, high-efficiency short daily haemodialysis (SDHD) has been proposed as an alternative for patients on renal replacement therapy. In this study, we have related our experience with this dialysis modality. METHODS: Twenty-six patients (16 males, mean age 35.6 +/- 14.7 years) were treated by SDHD for 33.6 +/- 18.5 months (range 6-57 months). The mean time on CHD before the switch to SDHD was 25.5 +/- 31.9 months (range 1-159 months). In 23 (88.5%) patients, native arteriovenous fistulae were used for vascular access. SDHD was performed six times a week, 1.5-2 h per session, and high flux polysulfone dialysers (surface area: 1.8 m(2)) were employed. The blood flow and dialysate flow rate were 350 and 800 ml/min, respectively. RESULTS: In this trial, the patient survival was 100%. The vascular access survival after 12, 24, 36 and 48 months on SDHD was 100, 89, 89 and 80%, respectively. There were three failures of vascular access in 72.7 patient-years (0.04 failures/patient-year). In 15 patients on SDHD during 36 consecutive months, the vascular access survival after 12, 24, 36 and 48 months was 100, 93, 93 and 84%, respectively. Also, in this group of patients, there were 0.27 hospitalizations/patient-year and 1.24 days of hospitalizations/patient-year. CONCLUSIONS: We concluded that in a long-time study of patients on SDHD the morbidity and mortality rate is very low. Furthermore, we observed that failures of vascular access are not a significant problem. Consequently, we believe that SDHD is a powerful renal replacement therapy for treatment of patients on maintenance haemodialysis.

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.

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"...

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.