Associations between 24-hour urinary sodium excretion and all-cause mortality in adults living in north China / 中华心血管病杂志

Objective: To investigate the associations between 24-hour urinary sodium excretion (24hUNaE) and all-cause mortality in adult Northern Chinese population. Methods: Data from this study were derived from the prospective urban and rural epidemiology (PURE) study in north China. Baseline information of all participants were obtained by face to face interview through trained research staffs based on questionnaires, and morning fasting urine samples of participants were collected to estimate 24hUNaE and 24-hour potassium excretion (24hUKE). Multivariable frailty Cox regression models were used to explore the association between 24hUNaE (<3.00, 3.00-3.99, 4.00-4.99, 5.00-5.99 and ≥6 g/d) and all-cause death. Results: A total of 27 310 participants were included in this study. The mean 24hUNaE was (5.84±1.73) g/d. After a median follow-up of 8.8 years, 1 024 participants died (3.7%), including 390 cardiovascular related deaths and 591 non-cardiovascular related deaths. The cause of death of the remaining patients could not be determined. Using 24hUNaE level of 4.00-4.99 g/d as the reference group, after fully adjustment, 24hUNaE ≥6.00 g/d was associated with an increased risk of all-cause death (HR=1.24, 95%CI: 1.02-1.49) and cardiovascular related death (HR=1.39, 95%CI: 1.02-1.88). 24hUNaE<3.00 g/d was associated with increased risk of all-cause mortality (HR=1.38, 95%CI: 0.96-1.99). There was no significant association between 24hUNaE and non-cardiovascular related death. Furthermore, using the combination of 24hUNaE 4.00-4.99 g/d and 24hUKE≥2.11 g/d as the reference group, the highest risk occurred in participants with the combination of low sodium (<3.00 g/d) and low potassium (<2.11 g/d). Conclusion: 24hUNaE equal or higher than 6 g/d or lower than 3 g/d is associated with increased risk of all-cause mortality and cardiovascular related death in Northern Chinese population. Besides, moderate sodium intake in combination with increased potassium intake might reduce the risk of all-cause death.

The role of urea-induced osmotic diuresis and hypernatremia in a critically ill patient: case report and literature review / O papel da diurese osmótica induzida por ureia na geração de hipernatremia no paciente crítico: relato de caso e revisão da literatura

Abstract Hypernatremia is a common electrolyte problem at the intensive care setting, with a prevalence that can reach up to 25%. It is associated with a longer hospital stay and is an independent risk factor for mortality. We report a case of hypernatremia of multifactorial origin in the intensive care setting, emphasizing the role of osmotic diuresis due to excessive urea generation, an underdiagnosed and a not well-known cause of hypernatremia. This scenario may occur in patients using high doses of corticosteroids, with gastrointestinal bleeding, under diets and hyperprotein supplements, and with hypercatabolism, especially during the recovery phase of renal injury. Through the present teaching case, we discuss a clinical approach to the diagnosis of urea-induced osmotic diuresis and hypernatremia, highlighting the utility of the electrolyte-free water clearance concept in understanding the development of hypernatremia.

Resumo A hipernatremia é um distúrbio eletrolítico comum no ambiente de terapia intensiva, com uma prevalência que pode chegar a 25%. Está associada a maior tempo de internação hospitalar e é um fator de risco independente para a mortalidade. Este relato ilustra um caso de hipernatremia de origem multifatorial no ambiente de terapia intensiva. Destacaremos o papel da diurese osmótica por geração excessiva de ureia, uma causa de hipernatremia pouco conhecida e subdiagnosticada. Este cenário pode estar presente em pacientes em uso de elevadas doses de corticoides, com sangramento gastrointestinal, em uso de dietas e suplementos hiperproteicos e estado de hipercatabolismo, especialmente durante a fase de recuperação de injúria renal. A seguir, discutiremos uma abordagem clínica para o diagnóstico da hipernatremia secundária à diurese osmótica induzida por ureia, destacando a importância do conceito de clearance de água livre de eletrólitos nesse contexto.

Estimation of daily sodium and potassium excretion from overnight urine of Japanese children and adolescents

BACKGROUND@#Estimates of daily sodium (Na) and potassium (K) excretion were explicitly biased when using equations for adults. We aimed to develop equations to estimate them using overnight urine from Japanese children and adolescents.@*METHODS@#The subjects comprised 70 students aged 10.49-15.76 years: validation group, n = 34; and verification group, n = 36. Each subject performed two operations of overnight spot urine (U@*RESULTS@#In validation, we formulated Na excretion (mg d@*CONCLUSION@#We obtained validated equations to estimate daily Na and K excretion with accessible variables such as Na, K, and Cr concentrations of overnight urine, body height and weight, and age for children and adolescents. When using the obtained equations, caution should be paid to small but definite biases and measurement errors.

Salt Preference is Linked to Hypertension and not to Aging / A Preferência ao Sal está Relacionada à Hipertensão e não ao Envelhecimento

Abstract Background: Seasoning is one of the recommended strategies to reduce salt in foods. However, only a few studies have studied salt preference changes using seasoning. Objectives: The aim of this study was to compare preference for salty bread, and if seasoning can change preference in hypertensive and normotensive, young and older outpatients. Methods: Outpatients (n = 118) were classified in four groups: older hypertensive subjects (OH) (n = 32), young hypertensive (YH) (n = 25); older normotensive individuals (ON) (n = 28), and young normotensive (YN) (n = 33). First, volunteers random tasted bread samples with three different salt concentrations. After two weeks, they tasted the same types of breads, with seasoning added in all. Blood pressure (BP), 24-hour urinary sodium and potassium excretion (UNaV, UKV) were measured twice. Analysis: Fisher exact test, McNamer's test and ANCOVA. Statistical significance: p < 0.05. Results: Systolic BP, UNaV, and UKV were greater in HO and HY and they had a higher preference for saltier samples than normotensive groups (HO: 71.9%, HY: 56% vs. NO: 25%, NY; 6%, p<0.01). With oregano, hypertensive individuals preferred smaller concentrations of salt, with reduced choice for saltier samples (HO: 71.9% to 21.9%, and HY: 56% to 16%, p = 0.02), NO preferred the lowest salt concentration sample (53.6% vs. 14.3%, p < 0.01), and NY further increased the preference for the lowest one (63.6% vs. 39.4%, p = 0.03). Conclusions: Older and younger hypertensive individuals prefer and consume more salt than normotensive ones, and the seasoned bread induced all groups to choose food with less salt. Salt preference is linked to hypertension and not to aging in outpatients.

Resumo Fundamento: Adicionar temperos aos alimentos é umas das estratégias recomendadas para diminuir a quantidade de sal nos alimentos. No entanto, poucos estudos investigaram alterações na preferência ao sal através do uso de temperos. Objetivos: O objetivo deste estudo foi comparar a preferência pelo pão salgado, e até que ponto o uso de temperos pode alterar as preferências dos indivíduos hipertensos e normotensos, pacientes ambulatoriais jovens e idosos. Métodos: Os pacientes ambulatoriais (n = 118) foram classificados em quatro grupos: idosos com hipertensão (IH) (n = 32), jovens hipertensos (JH) (n = 25); indivíduos idosos normotensos (IN) (n = 28), e jovens normotensos (JN) (n = 33). Primeiro, os voluntários provaram amostras aleatórias de pão com três diferentes concentrações de sal. Após duas semanas, eles provaram os mesmos tipos de pão, porém acrescidos de temperos. A pressão arterial (PA), e a excreção urinária de sódio e potássio de 24 horas (UNaV, UKV) foram medidas duas vezes. Análise: Teste exato de Fisher, teste de McNemar e teste ANCOVA. Significância estatística: p < 0,05. Resultados: A PA sistólica e a excreção urinária de sódio e potássio foram maiores nos grupos IH e JH, e eles tiveram maior preferência por amostras mais salgadas quando comparados com os grupos de normotensos (IH: 71,9%, JH: 56% vs. IN: 25%, JN; 6%, p < 0,01). Quando o orégano foi adicionado, a preferência dos indivíduos hipertensos foi pelas amostras com menores concentrações de sal, com uma diminuição da escolha por amostras mais salgadas (IH: 71,9% a 21,9%, e JH: 56% a 16%, p = 0,02); o grupo IN preferiu a amostra com a concentração de sal mais baixa (53,6% vs. 14,3%, p < 0,01) e no grupo JN aumentou ainda mais o número de indivíduos com preferência pela amostra com concentrações mais baixas de sal (63,6% vs. 39,4%, p = 0,03). Conclusões: Os idosos e jovens hipertensos preferem e consomem mais sal do que os normotensos, e o pão adicionado de tempero ajudou todos os grupos a escolher alimentos menos salgados. A preferência ao sal está ligada à hipertensão e não à idade nos pacientes ambulatoriais.

Fatores associados à relação sódio/potássio urinária em participantes do ELSA-Brasil / Factores asociados a la excreción urinaria sodio/potasio en participantes del ELSA-Brasil / Factors associated with urinary sodium/potassium ratio in participants in the ELSA-Brazil study

Resumo: Este estudo teve por objetivo identificar os fatores sociodemográficos associados à estimativa de alta relação de consumo de sódio/potássio. Foram avaliados 15.105 participantes, de 35 a 74 anos, de uma coorte de servidores públicos (ELSA-Brasil). Dados socioeconômicos foram coletados por meio de questionário e realizada coleta urinária de 12 horas noturnas para estimar o consumo de sódio e potássio. A relação sódio/potássio foi calculada em mmol/L e dividida em tercis: 1º tercil corresponde à "baixa" relação; 2º à "intermediária" e 3º tercil à "alta" relação sódio/potássio. Foram comparadas as proporções e médias segundo as classificações do tercil da relação sódio/potássio, utilizando-se os testes de qui-quadrado e análise de variância (ANOVA). Foram testados modelos brutos e ajustados de regressão logística multinomial, tendo como referência o 1º tercil. Os fatores associados à alta relação sódio/potássio foram: sexo masculino (OR = 1,78; IC95%: 1,60-1,98); indivíduos de 35 a 44 anos (OR = 1,71; IC95%: 1,33-2,19); Ensino Fundamental incompleto (OR = 2,38; IC95%: 1,78-3,18) e menor renda (OR = 1,47; IC95%: 1,26-1,73). Verificou-se que os homens, indivíduos mais jovens e de menor escolaridade e renda apresentaram médias mais elevadas da relação sódio/potássio.

Resumen: El objetivo de este estudio fue identificar los factores sociodemográficos asociados a la estimación respecto a la alta relación de consumo de sodio/potasio. Se evaluaron a 15.105 participantes, de 35 a 74 años, dentro de una cohorte de servidores públicos (ELSA-Brasil). Se recogieron datos socioeconómicos mediante un cuestionario y se realizó una toma nocturna de orina de 12 horas para estimar el consumo de sodio y potasio. La relación sodio/potasio se calculó en mmol/L y se dividió en terciles: 1er tercil corresponde a la "baja" relación; 2º tercil a la "intermedia" y 3er tercil a la "alta" relación sodio/potasio. Se compararon las proporciones y medias, según las clasificaciones del tercil de la relación sodio/potasio, utilizando los testes de chi-cuadrado y análisis de variancia (ANOVA). Se utilizaron modelos brutos y ajustados de regresión logística multinomial, teniendo como referencia el 1er tercil. Los factores asociados a la alta relación sodio/potasio fueron: sexo masculino (OR = 1,78; IC95%: 1,60-1,98); individuos de 35 a 44 años (OR = 1,71; IC95%: 1,33-2,19); enseñanza fundamental incompleta (OR = 2,38; IC95%: 1,78-3,18) y menor renta (OR = 1,47; IC95%: 1,26-1,73). Se verificó que los hombres, individuos más jóvenes y con menor escolaridad y renta presentaron medias más elevadas en la relación sodio/potasio.

Abstract: This study aimed to identify sociodemographic factors associated with high estimated sodium/potassium ratio. A total of 15,105 participants were assessed, from 35 to 74 years of age, from a cohort of public employees (ELSA-Brazil). Socioeconomic data were collected with a questionnaire, and 12-hour nighttime urine samples were collected to estimate sodium and potassium intake. Sodium/potassium ratio was calculated in mmol/L and divided into tertiles: 1st tertile, corresponding to "low"; 2nd tertile for "medium"; and 3rd tertile for "high" sodium/potassium ratio. The proportions and means were compared according to the classification of tertiles in the sodium/potassium ratio, using chi-square test and analysis of variance (ANOVA). Crude and adjusted multinomial logistic regression models were tested, with the 1st tertile as the reference. Factors associated with sodium/potassium ratio were: male sex (OR = 1.78; 95%CI: 1.60-1.98); age 35 to 44 years (OR = 1.71; 95%CI: 1.33-2.19); incomplete elementary schooling (OR = 2.38; 95%CI: 1.78-3.18); and lower income (OR = 1.47; 95%CI: 1.26-1.73). Men, younger individuals, and those with less schooling and income showed higher mean sodium/potassium ratio.

Association between estimated glomerular filtration rate and sodium excretion in urine of African descendants in Brazil: a population-based study / Associação entre taxa de filtração glomerular estimada e excreção urinária de sódio de descendentes de africanos no Brasil: um estudo populacional

ABSTRACT Introduction: Excessive salt intake is a risk factor for the development of chronic kidney disease (CKD). Objective: To evaluate the association between estimated glomerular filtration rate (eGFR) and sodium excretion in urine samples of Brazilians of African ancestry. Methods: Cross-sectional, population-based study of 1,211 Brazilians of African ancestry living in Alcântara City, Maranhão, Brazil. Demographic, nutritional, clinical, and laboratory data were analyzed. The urinary excretion of sodium was estimated using the Kawasaki equation. Calculations of eGFR were based on the Chronic Kidney Disease Epidemiology Collaboration equation. Multivariate linear-regression model was used to identify the relationship between sodium excretion and eGFR. Results: Mean age was 37.5±11.7 years and 52.8% were women. Mean urinary excretion of sodium was 204.6±15.3 mmol/day and eGFR was 111.8±15.3 mL/min/1.73m2. According to multivariate linear regression, GFR was independently correlated with sodium excretion (β=0.11; p<0.001), age (β=-0.67; p<0.001), female sex (β=-0.20; p<0.001), and body mass index (BMI; β=-0.09; p<0.001). Conclusions: The present study showed that age, female sex, BMI, and correlated negatively with eGFR. Sodium excretion was the only variable that showed a positive correlation with eGFR, indicating that high levels of urinary sodium excretion may contribute to hyperfiltration with potentially harmful consequences.

RESUMO Introdução: O consumo excessivo de sal é um fator de risco para o desenvolvimento de doença renal crônica (DRC). Objetivo: Avaliar a associação entre taxa de filtração glomerular estimada (eGFR) e excreção urinária de sódio em amostra isolada de urina de brasileiros de ascendência africana. Métodos: Trata-se de um estudo transversal de base populacional que incluiu 1.211 brasileiros de ascendência africana que vivem na cidade de Alcântara, no Maranhão. Foram analisados dados demográficos, nutricionais, clínicos e laboratoriais. A excreção urinária de sódio foi estimada usando a equação de Kawasaki. Os cálculos da TFGe foram realizados por meio da equação do Chronic Kidney Disease Epidemiology Collaboration. O modelo de regressão linear multivariada foi utilizado para identificar a relação entre excreção de sódio e TFGe. Resultados: A idade média foi de 37,5 ± 11,7 anos e 52,8% dos participantes eram mulheres. A média da excreção urinária de sódio, ao invés de excreção urinária média foi de 204,6 ± 15,3 mmol/dia e a TFGe foi de 111,8 ± 15,3 mL/min/1,73 m2. A regressão linear multivariada mostrou que a TFG correlacionou-se independentemente com a excreção de sódio (β = 0,11; p < 0,001), idade (β = -0,67; p < 0,001), sexo feminino (β = -0,20; p < 0,001) e índice de massa corporal (IMC; β = -0,09; p < 0,001). Conclusões: O presente estudo mostrou que idade, sexo feminino e IMC correlcionaram-se negativamente com TFGe. Ao negativamente correlacionados com TFGe. Excreção de sódio foi a única variável que mostrou correlação positiva com TFGe, indicando que a alta excreção urinária de sódio pode determinar um quadro de hiperfiltração, acarretando consequências adversas para a função renal a longo prazo.

Effect of phyllanthus niruri on metabolic parameters of patients with kidney stone: a perspective for disease prevention

ABSTRACT Phyllanthus niruri (P.niruri) or stone breaker is a plant commonly used to reduce stone risk, however, clinical studies on this issue are lacking. Objective: To prospectively evaluate the effect of P. niruri on the urinary metabolic parameters of patients with urinary lithiasis. Materials and Methods: We studied 56 patients with kidney stones <10mm. Clinical, metabolic, and ultrasonography assessment was conducted before (baseline) the use of P. niruri infusion for 12-weeks (P. niruri) and after a 12-week (wash out) Statistical analysis included ANOVA for repeated measures and Tukey's/McNemar's test for categorical variables. Significance was set at 5%. Results: Mean age was 44±9.2 and BMI was 27.2±4.4kg/m2. Thirty-six patients (64%) were women. There were no significant changes in all periods for anthropometric and several serum measurements, including total blood count, creatinine, uric acid, sodium, potassium, calcium, urine volume and pH; a significant increase in urinary potassium from 50.5±20.4 to 56.2±21.8 mg/24-hour (p=0.017); magnesium/creatinine ratio 58±22.5 to 69.1±28.6mg/gCr24-hour (p=0.013) and potassium/creatinine ratio 39.3±15.1 to 51.3±34.7mg/gCr24-hour (p=0.008) from baseline to wash out. The kidney stones decreased from 3.2±2 to 2.0±2per patient (p<0.001). In hyperoxaluria patients, urinary oxalate reduced from 59.0±11.7 to 28.8±16.0mg/24-hour (p=0.0002), and in hyperuricosuria there was a decrease in urinary uric acid from 0.77±0.22 to 0.54±0.07mg/24-hour (p=0.0057). Conclusions: P.niruri intake is safe and does not cause significant adverse effects on serum metabolic parameters. It increases urinary excretion of magnesium and potassium caused a significant decrease in urinary oxalate and uric acid in patients with hyperoxaluria and hyperuricosuria. The consumption of P.niruri contributed to the elimination of urinary calculi.

Efeito agudo da drenagem linfática manual sobre a natriurese e lipólise de mulheres jovens / Acute effect of manual lymphatic drainage on natriuresis and lipolysis in young women

Fundamentos: A importância da validação científica de técnicas coadjuvantes a diversos tratamentos de saúde é inquestionável. Desta forma, a influência da drenagem linfática manual (DLM) na natriurese e na lipólise sob interação de anticoncepcional oral precisa ser investigada. Objetivos: Avaliar o efeito agudo da DLM sobre a natriurese e lipólise de mulheres jovens usuárias ou não de anticoncepcional oral. Método: Participaram 29 mulheres não usuárias de anticoncepcional oral e 29 usuárias, autodeclaradas saudáveis, sedentárias e eutróficas. As análises foram realizadas em dois dias distintos, Controle (C), sem intervenção terapêutica e DLM. Nos dias C e DLM coletamos 4 amostras de urina com intervalos de 60 min. Seguimos o método de Leduc, abdomem e membros inferiores, durante 45 min. Analisamos o fluxo urinário e excreção urinária e sódio, glicerol e peptideo natriurético atrial. A normalidade dos dados foi analisada pelo teste Shapiro-Wilk. Os dados que não obedeceram à normalidade foram apresentados em mediana e intervalo interquartil (25%-75%), enquanto os que obedeceram foram apresentados em média ± erro padrão. O teste de Mann-Whitney foi usado para dados não pareados e Wilcoxon para dados pareados. Dados com normalidade foram avaliados pelo teste t-Student não pareado. O nível de significância estatística adotado foi de 5%. Resultados: O efeito agudo de uma sessão de DLM promove aumento da natriurese em mulheres não usuárias de anticoncepcional oral, por outro lado, em usuárias induz aumento na liberação de glicerol e de ANP

Background: The importance of scientific validation of supporting techniques to various treatments is unquestionable. In this context, the influence of manual lymphatic drainage (MLD) on natriuresis and lipolysis and its interaction with oral contraceptives still need to be investigated. Objectives: To evaluate the acute effect of MLD on natriuresis and lipolysis in young women using or not oral contraceptives. Methods: Twenty-nine non-users of oral contraceptives and 29 oral contraceptive users, self-reported healthy, sedentary, normal weight women were enrolled. Analyses were conducted on two different days ­ control (C), without therapeutic intervention and MLD day. Four urine samples were collected at 60-minute intervals. MLD was performed in lower limbs and abdomen for 45 min following the Leduc method. Urinary flow rat e and urinary sodium, glycerol and atrial natriuretic peptide excretion were analyzed. Data normality was tested by the Shapiro-Wilk test. Data without normal distribution were expressed as median and interquartile range (25%-75%), while normally distributed data were expressed as mean ± standard error. Mann-Whitney test was used for unpaired data and Wilcoxon test for paired data. Data with normal distribution were evaluated by the unpaired t-Student test. Statistical significance was set at 5%. Results: One MLD session had an acute effect on both groups, increasing natriuresis in non-users of oral contraceptives and glycerol and atrial natriuretic peptide excretion in oral contraceptive users. Conclusion: Oral contraceptives influence the effect of MLD on natriuresis

Validation of single measurement of 12-hour urine excretion for estimation of sodium and potassium intake. A longitudinal study

ABSTRACT BACKGROUND: Evaluation of sodium and potassium intake can be carried out using different methods. Biological markers are able to capture intra and inter-individual variability and are used as separate measurements of consumption. The aim of this study was to test the validity of a single measurement of urinary sodium and potassium excretion as representative of habitual intake. DESIGN AND SETTING: Longitudinal study, federal university. METHODS: Food consumption data from a sample of adult university students and public servants (25 to 74 years old) were collected through 24-hour records and 12-hour urinary sodium and potassium excretion at five different times over a one-year period. The dietary data were entered into a nutritional research data software system and the sodium and potassium intakes were estimated. The variables were tested for normal distribution using the Kolmogorov-Smirnov test. One-way analysis of variance or the Kruskal-Wallis test was used to evaluate means. Correlations between measurements using Pearson or Spearman coefficients were calculated. The degree of agreement between the five measurements was given by the intraclass correlation coefficient. RESULTS: Satisfactory agreement was found between the five measurements of urinary sodium and potassium excretion over a year, with little variability in consumption. CONCLUSION: A single measurement of urinary sodium and potassium accurately estimated the usual average consumption of these electrolytes. This can be used in population-based studies.

Bone turnover after bariatric surgery

ABSTRACT Objective The aim of the present study was to evaluate parameters of bone and mineral metabolism after bariatric surgery. Subjects and methods This sectional study included data from medical records from 61 bariatric surgery (BS) patients (minimum period of 6 months after the procedure) and from 30 class II and III obese patients as a control group (Cont), consisting of daily dietary intake of macronutrients, calcium and sodium, serum 25(OH)D and parathyroid hormone (PTH) and other biochemical serum and urinary parameters. Bone alkaline phosphatase (BAP), leptin, fibroblast growth factor-23 (FGF-23) and deoxypyridinoline (DPYD) were determined from available banked serum and urinary samples. Results Mean body mass index (BMI), median energy, carbohydrate, protein and sodium chloride consumption were significantly lower in the BS versus Cont, but calcium and lipids were not. No significant differences were found in ionized calcium, 25(OH)D, PTH and fibroblast growth factor 23 (FGF-23) between groups. Mean serum BAP was significantly higher for BS versus Cont and had a positive correlation with time after the surgical procedure. Mean serum leptin was significantly lower and median urinary DPYD higher in BS versus Cont. Conclusion The present study showed an increase in bone markers of both bone formation and resorption among bariatric patients up to more than 7 years after the surgical procedure, suggesting that an increased bone turnover persists even at a very long-term follow-up in such patients.

Perfil de riesgo litogénico en pacientes con urolitiasis en Paraguay / Lithogenic risk in patients from Paraguay with urolithiasis

The lithogenic risk profile is a graphical representation of metabolic factors and urinary saturation involved in the stone formation with their respective critical values. Aim: To determine the lithogenic risk profile in patients with urolithiasis. Material and Methods: Personal data such as anthropometric, history of diseases and family history of urolithiasis were recorded. Different compounds acting as promoters or inhibitors of crystallization were measured in serum and urine samples, and the data obtained were used to calculate urinary saturation using Equil software. Results: We included 30 men and 43 women with a median age of 45 (34-54) years. Overweight and family history of urolithiasis was reported in 63 and 32% respectively. Crystallization risk was detected in 74% of participants. The most common urinary abnormalities were hypocitraturia in 48% and hypercalciuria in 40%. Conclusions: The lithogenic profile revealed urinary saturation compatible with crystallization risk in 74% of the studied patients.

Fator natriurético atrial: ele é o responsável pela hiponatremia e natriurese em neurocirurgia? / Atrial natriuretic factor: is it responsible for hyponatremia and natriuresis in neurosurgery?

RESUMO Objetivo: Avaliar a presença de hiponatremia e natriurese, bem como suas associações com o fator natriurético atrial em pacientes de neurocirurgia. Métodos: Foram incluídos 30 pacientes submetidos à ressecção de tumor intracraniano e à clipagem de aneurisma cerebral. Os níveis plasmáticos e urinários de fator natriurético atrial foram medidos durante os períodos pré e pós-operatório. Resultados: Hiponatremia esteve presente em 63,33% dos pacientes, particularmente no primeiro dia pós-operatório. Observou-se natriurese em 93,33% dos pacientes, principalmente no segundo dia pós-operatório. Os níveis plasmáticos de fator natriurético atrial estavam aumentados em 92,60% dos pacientes em pelo menos um dos dias pós-operatórios, mas não houve associação estatisticamente significante entre fator natriurético atrial e sódio plasmático, e entre fator natriurético atrial e sódio urinário. Conclusão: Após neurocirurgia, na maior parte dos pacientes, estiveram presentes hiponatremia e natriurese; contudo, o fator natriurético atrial não pôde ser considerado diretamente responsável por tais alterações nos pacientes neurocirúrgicos. Provavelmente, há o envolvimento de outros fatores natriuréticos.

ABSTRACT Objective: To evaluate the presence of hyponatremia and natriuresis and their association with atrial natriuretic factor in neurosurgery patients. Methods: The study included 30 patients who had been submitted to intracranial tumor resection and cerebral aneurism clipping. Both plasma and urinary sodium and plasma atrial natriuretic factor were measured during the preoperative and postoperative time periods. Results: Hyponatremia was present in 63.33% of the patients, particularly on the first postoperative day. Natriuresis was present in 93.33% of the patients, particularly on the second postoperative day. Plasma atrial natriuretic factor was increased in 92.60% of the patients in at least one of the postoperative days; however, there was no statistically significant association between the atrial natriuretic factor and plasma sodium and between the atrial natriuretic factor and urinary sodium. Conclusion: Hyponatremia and natriuresis were present in most patients after neurosurgery; however, the atrial natriuretic factor cannot be considered to be directly responsible for these alterations in neurosurgery patients. Other natriuretic factors are likely to be involved.

Are patients with lichen planus really prone to urolithiasis? Lichen planus and urolithiasis

ABSTRACT Purpose to investigate whether patients with lichen planus (LP) are really prone to urolithiasis or not. Patients and Methods We performed a prospective analysis of 40 patients diagnosed with lichen planus (LP) (group I), and 40 volunteers did not have LP before (group II). Participants were all checked for urolithiasis by radiological investigations. Blood samples were analyzed for biochemistry parameters including calcium and uric acid. 24-h urine samples were analyzed to investigate oxalate, citrate calcium, uric acid, magnesium, sodium and creatinine. Results Men/women ratio and mean age were similar between group I and II (p>0.05). A presence or history of urolithiasis was detected in 8 (20%) and 2 (%5) patients in group I and II, respectively (p<0.05). Hypocitraturia was the most common anomaly with 35% (n:14) in group I. The rate of hypocitraturia in group II was 12.5% (n:5) and the difference was statistically significantly different (p=0.036). In group I, hyperuricosuria and hyperoxaluria followed with rates of 27.5% (n:11) and 25% (n:10), respectively. The rate of hyperuricosuria and hyperoxaluria were both 5% (n:2) in group II and the differences were significant (p<0.05). Hyperuricemia was another important finding in the patients with LP. It was detected in 13 (32.5%) patients in group I and in 1 (2.5%) participant in group II (p=0.001). Conclusion According to our results, metabolic disorders of urolithiasis were highly detected in the patients with LP. However, similar to the etiology of LP, the exact reasons for these metabolic abnormalities in LP remain a mystery.

Prediction of Cortical Defect Using C-Reactive Protein and Urine Sodium to Potassium Ratio in Infants with Febrile Urinary Tract Infection

PURPOSE: We investigated whether C-reactive protein (CRP) levels, urine protein-creatinine ratio (uProt/Cr), and urine electrolytes can be useful for discriminating acute pyelonephritis (APN) from other febrile illnesses or the presence of a cortical defect on 99mTc dimercaptosuccinic acid (DMSA) scanning (true APN) from its absence in infants with febrile urinary tract infection (UTI). MATERIALS AND METHODS: We examined 150 infants experiencing their first febrile UTI and 100 controls with other febrile illnesses consecutively admitted to our hospital from January 2010 to December 2012. Blood (CRP, electrolytes, Cr) and urine tests [uProt/Cr, electrolytes, and sodium-potassium ratio (uNa/K)] were performed upon admission. All infants with UTI underwent DMSA scans during admission. All data were compared between infants with UTI and controls and between infants with or without a cortical defect on DMSA scans. Using multiple logistic regression analysis, the ability of the parameters to predict true APN was analyzed. RESULTS: CRP levels and uProt/Cr were significantly higher in infants with true APN than in controls. uNa levels and uNa/K were significantly lower in infants with true APN than in controls. CRP levels and uNa/K were relevant factors for predicting true APN. The method using CRP levels, u-Prot/Cr, u-Na levels, and uNa/K had a sensitivity of 94%, specificity of 65%, positive predictive value of 60%, and negative predictive value of 95% for predicting true APN. CONCLUSION: We conclude that these parameters are useful for discriminating APN from other febrile illnesses or discriminating true APN in infants with febrile UTI.

Relationship between salt consumption measured by 24-h urine collection and blood pressure in the adult population of Vitória (Brazil)

High salt intake is related to an increase in blood pressure and development of hypertension. However, currently, there are no national representative data in Brazil using the gold standard method of 24-h urine collection to measure sodium consumption. This study aimed to determine salt intake based on 24-h urine collection in a sample of 272 adults of both genders and to correlate it with blood pressure levels. We used a rigorous protocol to assure an empty bladder prior to initiating urine collection. We excluded subjects with a urine volume <500 mL, collection period outside of an interval of 23-25 h, and subjects with creatinine excretion that was not within the range of 14.4-33.6 mg/kg (men) and 10.8-25.2 mg/kg (women). The mean salt intake was 10.4±4.1 g/day (d), and 94% of the participants (98% of men and 90% of women) ingested more than the recommended level of 5 g/d. We found a positive association between salt and body mass index (BMI) categories, as well as with salt and blood pressure, independent of age and BMI. The difference in systolic blood pressure reached 13 mmHg between subjects consuming less than 6 g/d of salt and those ingesting more than 18 g/d. Subjects with hypertension had a higher estimated salt intake than normotensive subjects (11.4±5.0 vs 9.8±3.6 g/d, P<0.01), regardless of whether they were under treatment. Our data indicate the need for interventions to reduce sodium intake, as well the need for ongoing, appropriate monitoring of salt consumption in the general population.

Renal biomarkers of male and female Wistar rats (Rattus norvegicus) undergoing renal ischemia and reperfusion

PURPOSE: To investigate biomarkers of acute renal injury in Wistar rats, subjected to left renal ischemia for 10 minutes, and then compare reperfusion at 24 hours, and at 5, 7, 14 and 21 days after the procedure. METHODS: Eight female and male rats between 60 and 81 days old were used in the Central Animal Facility of the UFMS. Assessed biomarkers included urine protein, urea, creatinine, glucose, sodium, potassium, urine alkaline phosphatase and gamma-glutamyl transferase activities, and protein-to-creatinine ratio; and in serum: urea, creatinine, sodium and potassium, fractional excretion of sodium, potassium, urine flow and creatinine clearance. RESULTS: Greater variance was observed in the parameters at 24 hours and at five days (p<0.05) after reperfusion. On the 21st day, these parameters approximated those obtained for the control group. CONCLUSIONS: Renal ischemia for 10 minutes was sufficient to raise urine levels of protein, glucose, fractional excretion of potassium, urea, creatinine clearance, urine activity of gamma-glutamyltransferase and alkaline phosphatase enzymes in the first 24 hours, up to five days after reperfusion, which may indicate risk of acute kidney injury, according to the RIFLE classification. .

Evaluation of Random Urine Sodium and Potassium Compensated by Creatinine as Possible Alternative Markers for 24 Hours Urinary Sodium and Potassium Excretion

Sodium and potassium intake was assessed on the basis of its respective excretion levels in 24 hr urine samples. However, owing to the inconvenience of collection, we evaluated random spot urine for alternative sodium and potassium excretion markers. We included 250 patients who submitted 24 hr- and spot urine for clinical tests. However, 22 patients who showed 24 hr urine creatinine excretion levels <500 mg/day were excluded, because these samples possibly resulted from incomplete urine collection. Moreover, 24 patients were excluded because of their use of diuretics during the urine collection period. We observed significant correlations between 24 hr urine sodium excretion and both the sodium/creatinine (r=0.34, P<0.0001) and the sodium/specific gravity unit (SGU) ratios (r=0.19, P=0.007) in random urine samples. Similarly, 24 hr urine potassium excretion and both the spot urine potassium/creatinine (r=0.47, P<0.0001) and potassium/SGU ratios (r=0.28, P<0.0001) were significantly correlated. Although the estimated sodium/creatinine and potassium/creatinine ratios showed a significant correlation with 24 hr urine sodium and potassium excretion, respectively, further studies are required to develop a spot urine test for individualized monitoring of sodium and potassium excretion.

Fluid distribution kinetics during cardiopulmonary bypass

OBJECTIVE: The purpose of this study was to examine the isovolumetric distribution kinetics of crystalloid fluid during cardiopulmonary bypass. METHODS: Ten patients undergoing coronary artery bypass grafting participated in this prospective observational study. The blood hemoglobin and the serum albumin and sodium concentrations were measured repeatedly during the distribution of priming solution (Ringer's acetate 1470 ml and mannitol 15% 200 ml) and initial cardioplegia. The rate of crystalloid fluid distribution was calculated based on 3-min Hb changes. The preoperative blood volume was extrapolated from the marked hemodilution occurring during the onset of cardiopulmonary bypass. Clinicaltrials.gov: NCT01115166. RESULTS: The distribution half-time of Ringer's acetate averaged 8 minutes, corresponding to a transcapillary escape rate of 0.38 ml/kg/min. The intravascular albumin mass increased by 5.4% according to mass balance calculations. The preoperative blood volume, as extrapolated from the drop in hemoglobin concentration by 32% (mean) at the beginning of cardiopulmonary bypass, was 0.6-1.2 L less than that estimated by anthropometric methods (p<0.02). The mass balance of sodium indicated a translocation from the intracellular to the extracellular fluid space in 8 of the 10 patients, with a median volume of 236 ml. CONCLUSIONS: The distribution half-time of Ringer's solution during isovolumetric cardiopulmonary bypass was 8 minutes, which is the same as for crystalloid fluid infusions in healthy subjects. The intravascular albumin mass increased. Most patients were hypovolemic prior to the start of anesthesia. Intracellular edema did not occur. .

Influence of clinical therapy and nutritional counseling on the recurrence of urolithiasis

PURPOSE: To evaluate the influence of combined clinical therapy and nutritional guidance on the recurrence of urolithiasis. METHODS: From our registry of patients with recurrent urolithiasis we selected 57 who had at least 5-years of follow-up. We collected 24h urine samples in order to analyze Ca, Na, uric acid, citrate, oxalate, and Mg concentrations and to assess urine volume. Patients filled out a clinical questionnaire before treatment, and abdominal radiographs and/or ultrasound were performed both before treatment and during the follow-up period. During follow-up, specific and individualized dietary advice was given based on the individual's metabolic disorders. Patients also received specific pharmacological treatment for their metabolic alterations. Outcome measures were metabolites in urine and the urolith recurrence rate. Pre- and post- intervention values were compared using tests as appropriate. RESULTS: Fifty six of the patients were male and the majority of patients were overweight. The mean BMI was 27 kg/m2. Urinary excretion of calcium, uric acid and sodium decreased significantly over the five year follow-up period. The number of uroliths that formed during the 5-year follow-up also decreased significantly compared to pre-treatment values. CONCLUSION: Individualized dietary advice combined with pharmacological treatment significantly reduces long-term urolithiasis recurrence. .

Dietary potassium intake and renal handling, and their impact on the cardiovascular health of normotensive Afro-Caribbeans / Ingesta dietética de potasio y manejo renal, y su impacto en la salud cardiovascular de los normotensos Afrocaribeños

OBJECTIVE: Recent nutritional profiles of dietary intake have indicated a shift from the ancient diet to the Western diet. The ancient diet provided high potassium and low sodium intake, which in turn led to sodium conservation and potassium excretion. This change in the dietary intake is expected to affect potassium and sodium handling in the kidneys. Numerous studies have been done to emphasize the importance of sodium handling by the kidneys and its impact on cardiovascular health . This study will investigate potassium intake and handling, and its impact on the cardiovascular health of a sample of normotensive Afro-Caribbeans by the possible modulation of the renin angiotensin aldosterone system (RAAS). METHODS: A sample of 51 normotensive Afro-Caribbean participants was recruited for the study. Participants were observed over a two-day period in which they were given a 24-hour ambulatory blood pressure monitor and a container to collect blood pressure data and a 24-hour urine sample. Anthropometric measurements were noted. Urinary electrolytes and supine plasma renin activity (PRA) were determined from the 24-hour urine collection and a blood sample. Dietary potassium intake was estimated based on dietary intake observations, and calculated based on the urinary potassium excretion. SPSS version 19 was used to analyse the data to make inferences. RESULTS: The daily potassium intake was observed to be 2.95 g/day and measured intake from the urinary potassium was between 4.95 and 7.32 g/day. Urinary potassium excretion was 3.66 (± 1.40) g/day. The urinary potassium excretion in the Afro-Caribbean sample in Barbados was higher than the other population samples. The averaged PRA of the participants (supine) was 0.778 (± 1.072) ng/mL/hour. The averaged nocturnal systolic blood pressure dip of the participants was 5.97 (± 4.324) %. There was no significant correlation between urinary potassium excretion, blood pressure, nocturnal systolic blood pressure dip and PRA. CONCLUSIONS: The Afro-Caribbean sample has an inadequate daily potassium intake based on the observed intake and recommended values, with a high urinary excretion of the electrolyte compared to other values in the literature. This high potassium excretion could have been partly due to low plasma renin activity levels in the study participants. As a possible consequence, an increase in the nocturnal peripheral resistance is a likely cause for the diminished systolic dip. The lack of correlations between dietary potassium excretion and the blood pressure parameters does not allow any firm inference of the electrolyte's handling and its impact on cardiovascular health in the normotensive Afro-Caribbean participants. However, further research is needed to get a more accurate daily potassium intake value, and a more statistically robust sample to assess whether potassium handling and blood pressure would be affected by a change in potassium intake.

OBJETIVO: Los perfiles nutricionales recientes de ingesta dietética han indicado un cambio de la dieta antigua a la dieta occidental. La dieta antigua ofrecía un consumo alto de potasio frente a un consumo bajo de sodio, lo que a su vez llevaba a la conservación del sodio y a la excreción del potasio. Se espera que este cambio en la ingesta dietética afecte el manejo del potasio y el sodio en los riñones. Se han realizado numerosos estudios con el fin de enfatizar la importancia del manejo del sodio por los riñones y su impacto en la salud cardiovascular. Este estudio investigará la ingesta y manejo del potasio, y su impacto en la salud cardiovascular de una muestra de normotensos afrocaribeños mediante la posible modulación del sistema renina-angiotensina-aldosterona (SRAA). MÉTODOS: Una muestra de 51 participantes normotensos afrocaribeños fue reclutada para el estudio. Los participantes fueron puestos bajo observación por un período de dos días, en los que recibieron un monitor ambulatorio para registrar la presión arterial por 24 horas, y un recipiente para recoger los datos de la presión arterial, y una muestra de orina de 24 horas. Se observaron las mediciones antropométricas. Los electrolitos urinarios y la actividad de renina plasmática (ARP) en posición supina, se determinaron a partir de la orina de 24 horas y una muestra de sangre. La ingesta dietética de potasio fue estimada en base a las observaciones hechas de la ingesta dietética, y se calculó a partir de la excreción del potasio urinario. La versión 19 del SPSS fue utilizada para analizar los datos y hacer inferencias. RESULTADOS: Se observó una ingestión diaria de potasio de 2.95 g/día, y la ingestión medida a partir del potasio urinario estuvo entre 4.95 y 7,32 g/día. La excreción del potasio urinario fue 3.66 (± 1.40) g/día. La excreción del potasio urinario en la muestra afrocaribeña en Barbados fue mayor que en las otras poblaciones. La actividad ARP promedio (supina) de los participantes fue 0.778 (± 1.072) ng/mL/hora. La caída nocturna promedio de la presión arterial sistólica de los participantes fue (± 4.324) 5.97%. No hubo ninguna correlación significativa entre la excreción del potasio urinario, la presión arterial, la caída nocturna de la presión arterial sistólica, y la actividad ARP. CONCLUSIONES: Partiendo de la base del consumo observado y los valores recomendados, la muestra afrocaribeña presenta una ingesta diaria inadecuada de potasio, con una alta excreción urinaria de electrólito, en comparación con otros valores en la literatura. Esta elevada excreción de potasio podría haberse debido en parte a niveles bajos de actividad de renina plasmática en los participantes del estudio. Una posible consecuencia es el aumento de la resistencia periférica nocturna como causa probable del descenso sistólico. La falta de correlación entre los parámetros de la presión arterial y la excreción de potasio dietético no permite ninguna inferencia sólida del manejo del electrólito y su impacto sobre la salud cardiovascular en los normotensos afrocaribeños participantes. Sin embargo, es necesario investigar más a fin de obtener un valor más exacto de la ingesta diaria de potasio y una muestra estadísticamente más sólida para evaluar si el manejo del potasio y la presión arterial podrían ser afectados por un cambio en la ingesta de potasio.