Is hemodiafiltration superior to high-flow hemodialysis in reducing all-cause and cardiovascular mortality in kidney failure patients? A meta-analysis of randomized controlled trials.

INTRODUCTION: Hemodiafiltration (HDF) and high-flux hemodialysis (hf-HD) are different methods of kidney replacement therapy (KRT) used for the treatment of kidney failure patients. A debate has raged over the last decade about the survival benefit of patients with the use of HDF compared with hf-HD, but with divergent results from randomized controlled trials. Therefore, this study aimed to perform a meta-analysis to compare HDF and hf-HD regarding all-cause and cardiovascular mortality. METHODS: PubMed and Cochrane databases were searched until July 19, 2023, for randomized clinical trials comparing HDF and hf-HD in patients on maintenance dialysis. A meta-analysis was performed using Stata 16.1, applying fixed or random effect models according to the heterogeneity between studies. FINDINGS: Of the 496 studies found, five met the inclusion criteria. Compared with the hf-HD group, the risk ratio (RR) for all-cause mortality with HDF use was 0.76 (95% CI: 0.67-0.88, I2 = 0%). HDF was associated with lower cardiovascular mortality, although the sensitivity analysis showed that the result differed between scenarios. Subgroup analysis showed lower all-cause mortality among patients without diabetes in the HDF group compared with hf-HD (RR 0.66, 95% CI: 0.51-0.81, I2 = 0%), but not in diabetic patients (RR = 0.89, 95% CI: 0.65-1.12, I2 = 0.0%). A subgroup analysis considering convection volumes was not performed, but the studies with the highest weight in the meta-analysis described convection volume as more than 20 L/session. DISCUSSION: More clinical studies considering critical risk factors, such as advanced age and preexisting cardiovascular disease, are needed to confirm the supremacy of HDF over hf-HD on the survival of patients treated by these two forms of kidney replacement therapy.

Does uric acid-lowering treatment slow the progression of chronic kidney disease? A meta-analysis of randomized controlled trials / ¿El tratamiento para reducir el ácido úrico retarda la progresión de la enfermedad renal crónica? Un metaanálisis de ensayos controlados aleatorizados

Introduction: Hyperuricemia has been proposed as an independent factor in the development and progression of chronic kidney disease (CKD). However, the effect of uric acid-lowering therapies on delaying CKD progression is still uncertain. Therefore, this systemic review aims to assess the effect of uric acid-lowering therapies on renal outcomes in pre-dialysis CKD patients. Methods: PubMed, Cochrane Library, and Lilacs databases were searched until April 24, 2021, for randomized clinical trials of CKD patients on uric acid-lowering treatment with xanthine-oxidase (XO) inhibitors. The weighted mean difference (WMD) or standard mean difference (SMD) with confidence interval (CI) were pooled using a random-effects model. Results: Among 567 studies found, eighteen met the inclusion criteria (n=2463 participants). Compared to the patient's control group, the WMD for the glomerular filtration ratio (GFR) and serum creatinine changes of the treated group was 2.02ml/min/1.73m2 (95%CI 0.41 to 3.63, P=0.014) and −0.19mg/dl (95%CI −0.34 to −0.04, I2=86.2%, P=0.011), respectively. Subgroup analyses showed that the difference in follow-up time and CKD population type in the studies may explain the controversy about the role of uric acid-lowering therapies in CKD progression. The GFR and creatinine outcomes analysis by types of XO inhibitors showed no difference between the control and treated groups. Uric acid-lowering therapies were strongly associated with decreased serum uric acid and urinary protein–creatinine ratio and urinary albumin–creatinine ratio. (AU)

Antecedentes: La hiperuricemia se ha propuesto como un factor independiente en el desarrollo y la progresión de la enfermedad renal crónica (ERC). Sin embargo, el efecto de las terapias para reducir el ácido úrico en el retraso de la progresión de la ERC aún es incierto. Por lo tanto, esta revisión sistémica tiene como objetivo evaluar el efecto de los tratamientos para reducir el ácido úrico sobre los resultados renales en pacientes con ERC antes de la diálisis. Métodos: Se realizaron búsquedas en las bases de datos de PubMed, Cochrane Library y Lilacs hasta el 24 de abril de 2021 en busca de ensayos clínicos aleatorizados de pacientes con ERC en tratamiento para reducir el ácido úrico con inhibidores de la xantina-oxidasa (XO). La diferencia de medias ponderada (DMP) o la diferencia de medias estándar (DME) con el intervalo de confianza (IC) se agruparon mediante un modelo de efectos aleatorizados. Resultados: Entre los 567 estudios encontrados, 18 cumplieron los criterios de inclusión (n=2.463 participantes). En comparación con los pacientes del grupo control, la DMP para la tasa de filtración glomerular (TFG) y los cambios en la creatinina sérica del grupo tratado fueron de 2,02ml/min/1,73m2 (IC del 95%: 0,41 a 3,63, P=0,014) y −0,19mg/dl (IC del 95%: −0,34 a −0,04, I2=86,2%, P=0,011), respectivamente. Los análisis de subgrupos mostraron que la diferencia en el tiempo de seguimiento y el tipo de población con ERC en los estudios puede explicar la controversia sobre el papel de las terapias para reducir el ácido úrico en la progresión de la ERC. El análisis de resultados de TFG y de creatinina por tipos de inhibidores de la XO no mostró diferencias entre el grupo control y el grupo tratado. Las terapias para reducir el ácido úrico se asociaron fuertemente con una disminución del ácido úrico sérico y de la relación proteína-creatinina urinaria y la relación albúmina-creatinina urinaria. (AU)

Is the vitamin D status of patients with COVID-19 associated with reduced mortality? A systematic review and meta-analysis.

To conduct a systematic review and meta-analysis of studies assessing the association between serum vitamin D status and mortality in patients with COVID- 19. We searched PubMed and Embase for studies addressing the association of serum vitamin D levels and COVID-19 mortality published until April 24, 2022. Risk ratios (RRs) and 95% confidence interval (CIs) were pooled using fixed or random effects models. The risk of bias was assessed using the Newcastle-Ottawa Scale. The meta-analysis included 21 studies that measured serum vitamin D levels close to the date of admission, of which 2 were case-control and 19 were cohort studies. Vitamin D deficiency was associated with COVID-19 mortality in the overall analysis but not when the analysis was adjusted to vitamin D cutoff levels < 10 or < 12 ng/mL (RR 1.60, 95% CI 0.93-2.27, I2 60.2%). Similarly, analyses including only studies that adjusted measures of effect for confounders showed no association between vitamin D status and death. However, when the analysis included studies without adjustments for confounding factors, the RR was 1.51 (95% CI 1.28-1.74, I2 0.0%), suggesting that confounders may have led to many observational studies incorrectly estimating the association between vitamin D status and mortality in patients with COVID-19. Deficient vitamin D levels were not associated with increased mortality rate in patients with COVID-19 when the analysis included studies with adjustments for confounders. Randomized clinical trials are needed to assess this association.

Does uric acid-lowering treatment slow the progression of chronic kidney disease? A meta-analysis of randomized controlled trials.

INTRODUCTION: Hyperuricemia has been proposed as an independent factor in the development and progression of chronic kidney disease (CKD). However, the effect of uric acid-lowering therapies on delaying CKD progression is still uncertain. Therefore, this systemic review aims to assess the effect of uric acid-lowering therapies on renal outcomes in pre-dialysis CKD patients. METHODS: PubMed, Cochrane Library, and Lilacs databases were searched until April 24, 2021, for randomized clinical trials of CKD patients on uric acid-lowering treatment with xanthine-oxidase (XO) inhibitors. The weighted mean difference (WMD) or standard mean difference (SMD) with confidence interval (CI) were pooled using a random-effects model. RESULTS: Among 567 studies found, eighteen met the inclusion criteria (n=2463 participants). Compared to the patient's control group, the WMD for the glomerular filtration ratio (GFR) and serum creatinine changes of the treated group was 2.02ml/min/1.73m2 (95%CI 0.41 to 3.63, P=0.014) and -0.19mg/dl (95%CI -0.34 to -0.04, I2=86.2%, P=0.011), respectively. Subgroup analyses showed that the difference in follow-up time and CKD population type in the studies may explain the controversy about the role of uric acid-lowering therapies in CKD progression. The GFR and creatinine outcomes analysis by types of XO inhibitors showed no difference between the control and treated groups. Uric acid-lowering therapies were strongly associated with decreased serum uric acid and urinary protein-creatinine ratio and urinary albumin-creatinine ratio. CONCLUSIONS: These findings suggest that uric acid-lowering treatment may slow CKD progress and reduce protein and albumin excretion. However, larger and properly powered randomized clinical trials with specific CKD populations are needed to confirm these findings.

Is the vitamin D status of patients with COVID-19 associated with reduced mortality? A systematic review and meta-analysis

ABSTRACT To conduct a systematic review and meta-analysis of studies assessing the association between serum vitamin D status and mortality in patients with COVID- 19. We searched PubMed and Embase for studies addressing the association of serum vitamin D levels and COVID-19 mortality published until April 24, 2022. Risk ratios (RRs) and 95% confidence interval (CIs) were pooled using fixed or random effects models. The risk of bias was assessed using the Newcastle-Ottawa Scale. The meta-analysis included 21 studies that measured serum vitamin D levels close to the date of admission, of which 2 were case- control and 19 were cohort studies. Vitamin D deficiency was associated with COVID-19 mortality in the overall analysis but not when the analysis was adjusted to vitamin D cutoff levels < 10 or < 12 ng/mL (RR 1.60, 95% CI 0.93-2.27, I2 60.2%). Similarly, analyses including only studies that adjusted measures of effect for confounders showed no association between vitamin D status and death. However, when the analysis included studies without adjustments for confounding factors, the RR was 1.51 (95% CI 1.28-1.74, I2 0.0%), suggesting that confounders may have led to many observational studies incorrectly estimating the association between vitamin D status and mortality in patients with COVID-19. Deficient vitamin D levels were not associated with increased mortality rate in patients with COVID-19 when the analysis included studies with adjustments for confounders. Randomized clinical trials are needed to assess this association.

Hypoparathyroidism and Fahr's syndrome: case series / Hipoparatireoidismo e síndrome de Fahr: série de casos

Abstract Hypoparathyroidism (HP) is a rare metabolic disorder and causes hypocalcemia because parathyroid hormone secretion is inadequate to mobilize calcium from bone and reabsorb calcium from kidney and gut. Anterior neck surgery is the most common cause of acquired HP and autoimmune HP is the next most common form in adults. The duration, severity, and rate of development of hypocalcemia determine the clinical presentation. A variety of organs can be affected by calcification, more frequently kidneys, but also joints, eyes, skin, vasculature, and other organ systems and, although rarely seen, intracerebral calcifications. We report four cases of bilateral basal ganglia calcifications (BGC) also known as Fahr's syndrome related to hypoparathyroidism. Fahr's syndrome is characterized by bilateral symmetrical calcification of areas of the brain that control movements including basal ganglia, thalamus, and others; it is a rare inherited or sporadic neurological disorder with a prevalence of less than 1/1.000.000. Main symptoms related to bilateral BGC include extra-pyramidal and cerebellar disorders, cognitive impairment, epileptic seizures, and psychiatric changes. BGC has been established as a possible outcome of HP. Its prevalence, demonstrated in the HP cohorts, varied significantly from 12 up to 74%. Currently, computed tomography (CT) is the most valuable method for diagnosis. The treatment include symptomatic support and identification of causes, but there is no specific treatment limiting the progression of calcification in the basal ganglia. Especially in HP, an early treatment can prevent calcification and neurophysiological disorders.

Resumo O hipoparatireoidismo (HP) é um distúrbio metabólico raro e causa hipocalcemia, pois a secreção do paratormônio é inadequada para mobilizar o cálcio dos ossos e reabsorver o cálcio dos rins e intestino. A cirurgia cervical anterior é a causa mais comum de HP adquirido. O HP autoimune é a segunda causa mais comum em adultos. A duração, gravidade e taxa de desenvolvimento da hipocalcemia determinam a apresentação clínica. Diversos órgãos podem ser afetados pela calcificação, mais frequentemente os rins, mas também articulações, olhos, pele, vasculatura e outros órgãos e, embora raramente vista, calcificações intracerebrais. Relatamos quatro casos de calcificações dos gânglios da base (CGB) bilaterais, também conhecidas como síndrome de Fahr relacionadas ao hipoparatireoidismo. A síndrome de Fahr é caracterizada pela calcificação bilateral simétrica de áreas do cérebro que controlam os movimentos incluindo os gânglios da base, tálamo e outros; é um distúrbio neurológico raro, hereditário ou esporádico, com uma prevalência 1/1.000.000. Os principais sintomas relacionados à CGB bilateral incluem distúrbios extrapiramidais e cerebelares, comprometimento cognitivo, convulsões e alterações psiquiátricas. A CGB foi estabelecida como uma possível consequência do HP. Sua prevalência, demonstrada nas coortes de HP, variou significativamente de 12 a 74%. Atualmente, a tomografia computadorizada (TC) é o método mais valioso para o diagnóstico. O tratamento inclui suporte sintomático e identificação de causas, mas não há tratamento específico limitando a progressão da calcificação nos gânglios da base. Especialmente no HP, um tratamento precoce pode prevenir calcificações e distúrbios neurofisiológicos.

Polymyxin Acute Kidney Injury: a case of severe tubulopathy / Nefropatia por polimixina B: a tubulopatia pode ser muito séria!

Abstract Polymyxins are antibiotics developed in the 1950s. Polymyxin-induced neurotoxicity has been often described in medical literature. The same cannot be said of nephrotoxicity or tubulopathy in particular. This report describes the case of a patient prescribed polymyxin B to treat a surgical wound infection, which led to significant increases in fractional excretion of calcium, magnesium, and potassium and subsequent persistent decreases in the levels of these ions, with serious consequences for the patient. Severe hypocalcemia, hypomagnesemia, and hypokalemia may occur during treatment with polymyxin. Calcium, magnesium and potassium serum levels must be monitored during treatment to prevent life-threatening conditions.

Resumo Polimixinas são um grupo de antibióticos desenvolvidos na década de 1950. Seus efeitos neurotóxicos são comumente descritos na literatura, porém há menos relatos sobre seus efeitos nefrotóxicos, especialmente tubulopatias. O objetivo deste relato é descrever o uso de polimixina B em uma paciente para tratamento de infecção de ferida operatória, promovendo grande aumento das frações de excreção de cálcio, magnésio e potássio e acarretando reduções graves e persistentes desses íons, com sérias consequências para a paciente. Hipocalcemia, hipomagnesemia e hipocalemia severas podem ocorrer durante terapia com polimixina e é sugerido que sejam monitorizadas as concentrações séricas desses eletrólitos durante o tratamento como forma de evitar condições de risco à vida.

Polymyxin Acute Kidney Injury: a case of severe tubulopathy.

Polymyxins are antibiotics developed in the 1950s. Polymyxin-induced neurotoxicity has been often described in medical literature. The same cannot be said of nephrotoxicity or tubulopathy in particular. This report describes the case of a patient prescribed polymyxin B to treat a surgical wound infection, which led to significant increases in fractional excretion of calcium, magnesium, and potassium and subsequent persistent decreases in the levels of these ions, with serious consequences for the patient. Severe hypocalcemia, hypomagnesemia, and hypokalemia may occur during treatment with polymyxin. Calcium, magnesium and potassium serum levels must be monitored during treatment to prevent life-threatening conditions.

Hypoparathyroidism and Fahr's syndrome: case series.

Hypoparathyroidism (HP) is a rare metabolic disorder and causes hypocalcemia because parathyroid hormone secretion is inadequate to mobilize calcium from bone and reabsorb calcium from kidney and gut. Anterior neck surgery is the most common cause of acquired HP and autoimmune HP is the next most common form in adults. The duration, severity, and rate of development of hypocalcemia determine the clinical presentation. A variety of organs can be affected by calcification, more frequently kidneys, but also joints, eyes, skin, vasculature, and other organ systems and, although rarely seen, intracerebral calcifications. We report four cases of bilateral basal ganglia calcifications (BGC) also known as Fahr's syndrome related to hypoparathyroidism. Fahr's syndrome is characterized by bilateral symmetrical calcification of areas of the brain that control movements including basal ganglia, thalamus, and others; it is a rare inherited or sporadic neurological disorder with a prevalence of less than 1/1.000.000. Main symptoms related to bilateral BGC include extra-pyramidal and cerebellar disorders, cognitive impairment, epileptic seizures, and psychiatric changes. BGC has been established as a possible outcome of HP. Its prevalence, demonstrated in the HP cohorts, varied significantly from 12 up to 74%. Currently, computed tomography (CT) is the most valuable method for diagnosis. The treatment include symptomatic support and identification of causes, but there is no specific treatment limiting the progression of calcification in the basal ganglia. Especially in HP, an early treatment can prevent calcification and neurophysiological disorders.

A Randomized Trial of Short-term Treatment with Folic Acid to Reduce the Oxidative Stress of Patients with Chronic Kidney Disease.

BACKGROUND: Increased generation of reactive oxygen and nitrogen species in chronic kidney disease (CKD) patients leads to increased oxidative stress. The antioxidant capacity of folic acid has been shown to scavenge radicals efficiently. OBJECTIVE: The current study was carried out to examine the effects of folic acid treatment on biochemical and oxidative stress biomarkers in patients in different stages of CKD. METHODS: This was a randomized, non-blinded, clinical trial that assessed the effects of 3 months of treatment with 5 mg of folic acid daily or no treatment in 113 outpatients within CKD stages 3a and 3b. At the end of the intervention, we analyzed the data of 66 patients treated with folic acid and 47 in the control group. Serum homocysteine levels and biochemical and oxidative/nitrosative stress biomarkers were analyzed in all patients. RESULTS: In most patients, folic acid treatment normalized homocysteine levels and increased antioxidant enzyme activity (paraoxonase 1) and decreased sulfhydryl (SH) groups. In addition, oxidative biomarkers (products of nitric oxide and lipid hydroperoxide) were significantly lower post-treatment compared to baseline in the active intervention group. In the no active intervention group, no statistically significant effects were found on the oxidative and biochemical biomarkers. CONCLUSION: Folic acid treatment in stages 3a-4 CKD patients effectively ameliorated their hyperhomocysteinemia and increased the activity of antioxidant enzymes, as well as decreased the levels of pro-oxidant biomarkers in stage G3a and G3b CKD patients. Folic acid treatment attenuated oxidative/nitrosative stress and may be considered as a possible strategy to improve redox status and diminish the damages associated with oxidative/nitrosative stress in CKD patients. Further studies are needed to confirm these findings. Clinical Trials Registration No.: This study is registered in the Brazilian Record of Clinical Trials (ReBEC), under reference RBR-2bfthr.

Recommendations from the Brazilian Society of Nephrology regarding the use of cloth face coverings, by chronic kidney patients in dialysis, during the new coronavirus pandemic (Covid-19).

These recommendations were created after the publication of informative note 3/2020- CGGAP/DESF/SAPS/MS, of April 4, 2020, in which the Brazilian Ministry of Health recommended the use of a cloth mask by the population, in public places. Taking into account the necessary prioritization of the provision of Personal Protective Equipment (PPE) for patients with suspected or confirmed disease, as well as for healthcare professionals, the SBN is favorable concerning the wear of cloth masks by chronic kidney patients in dialysis, in public settings, except in the dialysis setting. The present recommendations have eleven items, related to this rationale, the procedures, indications, contraindications, as well as appropriate fabrics for the mask, and hygiene care to be adopted. These recommendations may change, at any time, in the light of new evidence.

Covid-19 (Sars-Cov-2 Infection) Information for Patients with Predialytic Chronic Kidney Disease.

Patients with Chronic Kidney Disease are among those individuals at increased risk for developing more serious forms of Covid-19. This increased risk starts in the pre-dialysis phase of the disease. Providing useful information for these patients, in language that facilitates the understanding of the disease, can help nephrologists and other healthcare professionals to establish a more effective communication with these patients and help minimize contagion and the risks of serious illness in this population.

Good Practice Recommendations from the Brazilian Society of Nephrology to Dialysis Units Concerning the Pandemic of the New Coronavirus (Covid-19).

Dialysis units are environments potentially prone to the spread of Covid-19. Patients cannot suspend treatment, and they often have comorbidities, which assigns them a higher risk and worse prognosis. The Brazilian Society of Nephrology prepared this document of good practices, whose technical recommendations deal with general measures that can be implemented to reduce the risk of transmission and prevent the spread of the disease in the unit.

Non-recovery of renal function is a strong independent risk factor associated with mortality in AKI patients.

INTRODUCTION: Acute kidney injury (AKI) is a recurrent complication in the intensive care unit (ICU) and is associated with negative outcomes. OBJECTIVE: To investigate factors associated with mortality in critically ill AKI patients in a South Brazilian ICU. METHODS: The study was observational retrospective involving AKI patients admitted to the ICU between January 2011 and December 2016 of at least 18 years old upon admission and who remained in the ICU at least 48 hours. Comparisons between selected characteristics of survivor and non-survivor groups were done using univariate analysis; multivariate logistic regression was applied to determine factors associated with patient mortality. RESULTS: Of 838 eligible patients, 613 participated in the study. Men represented the majority (61.2%) of the patients, the median age was 53 years, and the global mortality rate was 39.6% (n= 243). Non-recovery of renal function after AKI (OR= 92.7 [38.43 - 223.62]; p <0.001), major surgery-associated AKI diagnosis (OR= 16.22 [3.49 - 75.38]; p <0.001), and the use of vasoactive drugs during the ICU stay (OR = 11.49 [2.46 - 53.70]; p <0.002) were the main factors independently associated with patient mortality. CONCLUSION: The mortality rate observed in this study was similar to that verified in other centers. Non-recovery of renal function was the variable most strongly associated with patient mortality, suggesting that the prevention of factors that aggravate or maintain the AKI episode should be actively identified and mitigated, possibly constituting an important strategy to reduce mortality in AKI patients.

Vitamin D deficiency is not associated with increased oxidative stress in chronic kidney disease pre-dialysis patients.

INTRODUCTION: The progressive decline in 25-hydroxyvitamin D [25(OH)D] in chronic kidney disease (CKD) limits the kidney ability of synthesizing the vitamin. Vitamin D deficiency as defined by KDIGO (25(OH)D <20 ng/mL) is prevalent in CKD patients and associated to oxidative stress (OS). We studied a possible association between vitamin D deficiency and OS in pre-dialysis patients. METHODS: A cross-sectional study with 206 CKD patients was carried out. Laboratory tests for 25(OH)D, 1,25(OH)2D, inflammatory markers, and OS were added to routine tests including creatinine, albumin, calcium, phosphorus, alkaline phosphatase, iPTH, glucose, hemoglobin, uric acid, total cholesterol, LDL, HDL, and triglycerides. RESULTS: Vitamin D deficiency was present in 55 CKD patients and normal vitamin D levels were seen in 149 patients. There was a significant association between vitamin D and estimated glomerular filtration rate (eGRF). Homocysteine levels were best predicted by eGRF, sex, and age; high sensitivity C-reactive protein (hsCRP) by staging and BMI; nitric oxide metabolites (NOx) were increased in late disease; leptin was influenced by BMI and higher in women than man; and adiponectin levels were higher in women. CONCLUSIONS: OS biomarkers were not correlated with vitamin D deficiency but increased NOx were seen in stages 4-5 CKD patients. Even though a relatively large number of CKD patients was included and a broad number of OS and inflammatory biomarkers were used in this studied we failed to find an association between vitamin D levels and eGRF. More studies are needed to evaluate the influence of vitamin D status in OS in pre-dialysis CKD patients.

Recommendations from the Brazilian Society of Nephrology regarding the use of cloth face coverings, by chronic kidney patients in dialysis, during the new coronavirus pandemic (Covid-19) / Recomendações da Sociedade Brasileira de Nefrologia quanto ao uso de máscaras de pano por pacientes renais crônicos em diálise, durante a pandemia pelo novo coronavírus (Covid-19)

ABSTRACT These recommendations were created after the publication of informative note 3/2020- CGGAP/DESF/SAPS/MS, of April 4, 2020, in which the Brazilian Ministry of Health recommended the use of a cloth mask by the population, in public places. Taking into account the necessary prioritization of the provision of Personal Protective Equipment (PPE) for patients with suspected or confirmed disease, as well as for healthcare professionals, the SBN is favorable concerning the wear of cloth masks by chronic kidney patients in dialysis, in public settings, except in the dialysis setting. The present recommendations have eleven items, related to this rationale, the procedures, indications, contraindications, as well as appropriate fabrics for the mask, and hygiene care to be adopted. These recommendations may change, at any time, in the light of new evidence.

RESUMO As presentes recomendações foram elaboradas após a publicação da Nota Informativa nº 3/2020 CGGAP/DESF/SAPS/MS, em 4 de abril de 2020, na qual o Ministério da Saúde recomenda o uso de máscara de pano por toda a população, em locais públicos. Levando-se em consideração a necessária priorização do fornecimento de Equipamentos de Proteção Individual (EPIs) para pacientes com suspeita ou confirmação da doença, assim como para profissionais de saúde, a Sociedade Brasileira de Nefrologia (SBN) posicionou-se favoravelmente ao uso de máscaras de pano por pacientes renais crônicos em diálise, em ambientes públicos, exceto no ambiente da diálise. As presentes recomendações englobam onze itens relativos ao que é racional para posicionamento, procedimentos, indicações, contraindicações, assim como tecidos apropriados para confecção e os cuidados de higiene a serem adotados. Essas recomendações poderão ser modificadas a qualquer momento, à luz de novas evidências.

Covid-19 (sars-cov-2 infection) information for patients with predialytic chronic kidney disease / Informações para pacientes com doença renal crônica pré-dialítica sobre Covid-19 (infecção pelo SARS-CoV-2)

ABSTRACT Patients with Chronic Kidney Disease are among those individuals at increased risk for developing more serious forms of Covid-19. This increased risk starts in the pre-dialysis phase of the disease. Providing useful information for these patients, in language that facilitates the understanding of the disease, can help nephrologists and other healthcare professionals to establish a more effective communication with these patients and help minimize contagion and the risks of serious illness in this population.

RESUMO Pacientes com Doença Renal Crônica estão entre os indivíduos de risco aumentado para desenvolvimento de formas mais sérias de Covid-19. Esse risco aumentado inicia-se já na fase pré-dialítica da doença. Fornecer informações úteis para esses pacientes, em linguagem que facilite o entendimento da doença, pode ajudar nefrologistas e outros profissionais de saúde a estabelecerem uma comunicação mais efetiva com esses pacientes e ajudar a minimizar o contágio e os riscos de doença grave nessa população.

Functional iron deficiency in patients on hemodialysis: prevalence, nutritional assessment, and biomarkers of oxidative stress and inflammation / Deficiência funcional de ferro em pacientes em hemodiálise: prevalência, avaliação nutricional e de biomarcadores de estresse oxidativo e de inflamação

Abstract Introduction: Anemic patients with chronic kidney disease (CKD) can be divided into anemic patients without or with functional iron deficiency (FID). The increase in the number of cases of hemosiderosis in patients on hemodialysis (HD) attributed to excessive intravenous iron replacement has called for the investigation of the factors involved in the genesis of FID. Objectives: This study aimed to describe the prevalence of FID in patients with CKD on HD, characterize the included individuals in terms of clinical and workup parameters, and assess their nutritional, oxidative stress, and inflammation statuses. This cross-sectional study assembled a convenience sample of 183 patients with CKD on HD treated in Southern Brazil. Patients meeting the inclusion and exclusion criteria were divided into two groups, one with anemic subjects with FID and one with anemic patients without FID. Participants answered a questionnaire probing into socio-epidemiological factors, underwent anthropometric measurements, and were tested for markers of anemia, oxidative stress, inflammation, and nutrition. Statistical analysis: The date sets were treated on software package GraphPad InStat version 3.1. Variables were tested with the Kolmogorov-Smirnov, chi-square, Student's t, and Mann-Whitney tests. Statistical significance was attributed to differences with a p < 0.05. Results: Markers of inflammation were not statistically different between the two groups. Markers of anemia and nutrition were significantly lower in patients with FID. Patients with FID were prescribed higher doses of parenteral iron (p < 0,05). Discussion: FID was associated with lower nutritional marker levels, but not to increased levels of markers of inflammation or oxidative stress, as reported in the literature. Additional studies on the subject are needed.

Resumo Introdução: A anemia na DRC pode ser dividida em anemia sem deficiência funcional de ferro e com deficiência funcional de ferro (ADFF). Diante do aumento dos casos de hemossiderose em pacientes em hemodiálise, atribuídos à reposição excessiva de ferro endovenoso, maiores conhecimentos sobre os fatores envolvidos na gênese da ADFF são importantes. Objetivos: documentar a prevalência de ADFF em renais crônicos em hemodiálise. Caracterizar clínica e laboratorialmente os portadores de ADFF em HD e avaliar o estado nutricional, estresse oxidativo e inflamatório. Estudo transversal, amostra de conveniência, envolvendo 183 renais crônicos em hemodiálise no sul do Brasil. Após aplicação dos critérios de exclusão, os pacientes foram separados em dois grupos: portadores de anemia com e sem deficiência funcional de ferro. Foram submetidos a questionário socioepidemiológico, à análise antropométrica e análise laboratorial dos marcadores de anemia, estresse oxidativo, inflamatórios e nutricionais. Análise estatística: programa GraphPad InStat versão 3.1. Foram aplicados os testes: Kolmogorov-Smirnov, qui-quadrado, t de Student e Mann-Whitney. Nível de significância adotado de 5%. Resultados: não houve diferença significativa nos marcadores inflamatórios entre os dois grupos. Houve diferença significativa nos marcadores de anemia e nutrição, significativamente menores nos pacientes com ADFF. Pacientes com ADFF receberam doses mais elevadas de ferro parenteral (p < 0,05). Discussão: ADFF esteve associada a menores valores de marcadores nutricionais, mas não esteve associada a marcadores inflamatórios ou de estresse oxidativo aumentados, como relatado na literatura. Estudos adicionais sobre o tema são necessários.