Metabolic and volume status evaluation of hemodialysis patients with and without residual renal function in the long interdialytic interval / Avaliação metabólica e volêmica no maior intervalo interdialítico de pacientes em hemodiálise com e sem função renal residual

Abstract Introduction: It is unclear whether residual renal function (RRF) in dialysis patients can attenuate the metabolic impact of the long 68-hour interdialytic interval, in which water, acid, and electrolyte accumulation occurs. Objective: to evaluate serum electrolyte levels, water balance, and acid-base status in dialytic patients with and without RRF over the long interdialytic interval (LII). Methodology: this was a single-center, cross-sectional, and analytical study that compared patients with and without RRF, defined by diuresis above 200 mL in 24 hours. Patients were weighed and serum samples were collected for biochemical and gasometric analysis at the beginning and at the end of the LII. Results: 27 and 24 patients with and without RRF were evaluated, respectively. Patients without RRF had a higher increase in serum potassium during the LII (2.67 x 1.14 mEq/L, p < 0.001), reaching higher values at the end of the study (6.8 x 5.72 mEq/L, p < 0.001) and lower pH value at the beginning of the interval (7.40 x 7.43, p = 0.018). More patients with serum bicarbonate < 18 mEq/L (50 x 14.8%, p = 0.007) and mixed acid-base disorder (57.7 x 29.2%, p = 0.042), as well as greater interdialytic weight gain (14.67 x 8.87 mL/kg/h, p < 0.001) and lower natremia (137 x 139 mEq/L, p = 0.02) at the end of the interval. Calcemia and phosphatemia were not different between the groups. Conclusion: Patients with RRF had better control of serum potassium, sodium, acid-base status, and volemia throughout the LII.

Resumo Introdução: Não se sabe ao certo se a função renal residual (FRR) de pacientes dialíticos pode atenuar o impacto metabólico do maior intervalo interdialítico (MII) de 68 horas, no qual ocorre acúmulo de volume, ácidos e eletrólitos. Objetivo: Avaliar os níveis séricos de eletrólitos, balanço hídrico e status ácido-básico de pacientes dialíticos com e sem FRR ao longo do MII. Metodologia: Tratou-se de estudo unicêntrico, transversal e analítico, que comparou pacientes com e sem FRR, definida como diurese acima de 200 mL em 24 horas. Para tal, os pacientes foram pesados e submetidos à coleta de amostras séricas para análise bioquímica e gasométrica no início e fim do MII. Resultados: Foram avaliados 27 e 24 pacientes com e sem FRR, respectivamente. Pacientes sem FRR apresentaram maior aumento de potássio sérico durante o MII (2,67 x 1,14 mEq/L, p < 0,001) atingindo valores mais elevados no fim (6,8 x 5,72 mEq/L, p < 0,001); menor valor de pH no início do intervalo (7,40 x 7,43, p = 0,018), maior proporção de pacientes com bicarbonato sérico < 18 mEq/L (50 x 14,8 %, p = 0,007) e distúrbio ácido-básico misto (70,8 x 42,3 %, p = 0,042), além de maior ganho de peso interdialítico (14,67 x 8,87 mL/kg/h, p < 0,001) e menor natremia (137 x 139 mEq/L, p = 0,02) no fim do intervalo. A calcemia e fosfatemia não foram diferentes entre os grupos. Conclusão: Pacientes com FRR apresentaram melhor controle dos níveis séricos de potássio, sódio, status ácido-básico e da volemia ao longo do MII.

Comparison of Urinary Protein Creatinine Index (uPCI) and Dipsticks for the Prediction of Renal Dysfunction in Chronic Cigarette Smokers.

Background: Proteinuria is recognized as one of the earliest sign of renal function deterioration in chronic smokers. Proteinuria occurs due to alteration in glomerular permeability and later due to failure of reabsorption of filtered protein by the tubular cells. Normally, most healthy adults excrete 20 – 150 mg of protein in urine over 24 hours. However, it is difficult to collect 24 hrs urine samples. Objectives: To advocate the use of PCI (protein creatinine index) in assessment of proteinuria and to compare dipstick result with PCI in the assessment of proteinuria in chronic cigarette smokers. Material & Methods: A total of 30 cigarette smokers and 40 age and sex matched controls were included for the study. A random specimen of urine collected from each cigarette smoker and non- smoker was tested quantitatively by manual sulfosalicylic acid colorimetric method for the estimation of protein concentration. Creatinine concentration in each specimen was measured by modified Jaffe’s method and the urinary PCI was calculated. Results: Normal range of PCI which has been established in this study is 50 to 259. Significantly higher amounts of protein were found to be excreted in urine in chronic smokers (9.313 ± 4.003 mg/dl) as compared to healthy non smokers (7.738 ± 2.05 mg/dl). On comparison of PCI between healthy non smoker and chronic smoker subjects, PCI has been found to be significantly elevated in chronic smokers (healthy non smoker- 118.32 ± 56.86, chronic smoker- 180.1 ± 88.23) (p=0.001). Conclusion: PCI of random urine sample can provide a very useful, simple and convenient method for the quantitative assessment of proteinuria to confirm the advent of kidney damage, avoiding the drawbacks of 24 hrs urine collection.

Ras oncoprotein level and urinary enzymes activity as sensitive indicators of renal injury in acute and chronic renal failure

Sixty-one patients with renal failure and ten healthy controls were included in this study. Patients were subdivided into three groups; group I included 20 patients with acute renal failure [ARF], group II included 20 patients with chronic renal failure [CRF] and group III included 21 patients with renal impairment [RI]. Serum ras oncoprotein was significantly higher in patients with ARF, CRF and RI compared with the controls. Ras oncoprotein level, sialic acid level and urinary excretion of the studied enzymes were not changed significantly with increased degrees of albuminuria or with the presence of casts, RBCs or pus cells in urine. Neither kidney size sonographically nor degree of echogenicity has an effect on the studied bioindices. The study revealed statistically significant correlations between ras oncogene expression and urinary enzymes excreted during renal damage

Estimativa da funçäo renal na síndrome de imunodeficiência adquirida - nota prévia / Estimative of the renal function in acquired immunodeficiency syndrome - previous note

Métodos de estimativa da taxa de depuraçao da creatinina (CCr) a partir do nível da creatinina sérica têm sido largamente utilizados. Tais estimadores, contudo têm mostrado precisao variável de acordo com a populaçao estudada. Neste estudo avaliamos o grau de correlaçao e a precisao de três diferentes métodos de estimativa da CCr: as fórmulas de Cockcroft e Gault (CG), de Jellife (J) e o monograma de Sirsbaek-Nielsen (S-N) em um grupo de pacientes com a Síndrome de Imunodeficiência Adquirida (SIDA). Estudamos 43 pacientes (35 homens, 8 mulheres; idade = 37 + 9,1 anos). A média da CCr foi 82 + 43 ml/min. Os coeficientes de correlaçao (r) para (J) foi de 0,62 (IC 95 por cento = 0,39-0,77), enquanto para os outros dois métodos foi de 0,69 (IC 95 por cento = 0,49-0,82). Calculamos o erro de prediçao (EP) e o percentual de erro absoluto de prediçao (PEAP). A média do erro de prediçao tendeu a ser maior com (J) (18 + 38,6) que com (CG) (-3 + 27,5) ou (S-N) (-0,2 + 27,3) nao havendo, entretanto, significância estatística. O mesmo sucedeu ao PEAP que foi respectivamente, de 41 + 47 por cento, 26 + 23 por cento e 27 + 26 por cento. Subdividimos a populaçao em três grupos de acordo com a faixa de CCr: < 80ml/min (n = 15), ( 80 e ( 120 (n = 20) e > 120ml/min (n = 8). Embora as diferenças nao tenham alcançado a significância estatística, houve tendência a um maior PEAP no grupo com CCr < 80ml/min com todos os métodos estudados. Os valores médios de EP indicaram tendência a superestimaçao da CCr neste grupo de pacientes (J = 31,5 + 37; CG = 12,4 + 17; S-N = 17 + 19,5). Estes resultados preliminares sugerem que os métodos de estimativa estudados tendam a causar importante superestimaçao da CCr nos pacientes com SIDA e insuficiência renal, o que pode ocasionar ajustes inadequados na dosagem de drogas excretadas pelo rim, nestes pacientes.