What is central to renal nutrition: protein or sodium intake?

Historically, nutrition intervention has been primarily focused on limiting kidney injury, reducing generation of uraemic metabolites, as well as maintaining nutrition status and preventing protein-energy wasting in patients with chronic kidney disease (CKD). This forms an important rationale for prescribing restricted protein diet and restricted salt diet in patients with CKD. However, evidence supporting a specific protein intake threshold or salt intake threshold remains far from compelling. Some international or national guidelines organizations have provided strong or 'level 1' recommendations for restricted protein diet and restricted salt diet in CKD. However, it is uncertain whether salt or protein restriction plays a more central role in renal nutrition management. A key challenge in successful implementation or wide acceptance of a restricted protein diet and a restricted salt diet is patients' long-term dietary adherence. These challenges also explain the practical difficulties in conducting randomized trials that evaluate the impact of dietary therapy on patients' outcomes. It is increasingly recognized that successful implementation of a restricted dietary prescription or nutrition intervention requires a highly personalized, holistic care approach with support and input from a dedicated multidisciplinary team that provides regular support, counselling and close monitoring of patients. With the advent of novel drug therapies for CKD management such as sodium-glucose cotransporter-2 inhibitors or non-steroidal mineralocorticoid receptor antagonist, it is uncertain whether restricted protein diet and restricted salt diet may still be necessary and have incremental benefits. Powered randomized controlled trials with novel design are clearly indicated to inform clinical practice on recommended dietary protein and salt intake threshold for CKD in this new era.

Nutrition Management for Chronic Kidney Disease: Differences and Special Needs for Children and Adults

Common goals of nutritional therapy across the spectrum of pediatric and adult chronic kidney disease (CKD) include maintaining normal body mass and composition and reducing associated morbidity and mortality. Adult nephrologists caring for children and adolescents may be challenged by the existing complexities in identifying and interpreting the nutritional status and growth in children. Pediatric nephrologists may face situations that call for a sound knowledge of assessing nutritional status and providing nutrition therapy for adolescents and young adults. One important additional nutrition goal in children is to achieve normal growth and development. Children are growing and therefore need more calories and nutrients than just maintaining their body weight and composition. Lack of weight and height gain actually is considered failure to thrive in children. Some fundamental differences in approaches to nutritional therapy in CKD are necessitated based on the etiology of CKD. A large proportion of adults with CKD are diabetics, so the approach would be a low-carbohydrate diet. Children with CKD, especially young ones, often are anorexic, so calorie supplements that could include quite a lot of carbohydrates often are prescribed. More adults with CKD have hypertension and atherosclerotic comorbidities, which result in recommendations for low-salt and low-fat diets. Children with CKD often have salt and electrolyte wasting disease states and would require normal- or even high-salt diets, and fats often are included in supplements to bolster calorie intake. Low-protein diets often are recommended in adults with predialysis CKD to slow disease progression. Children are growing and have a higher protein daily requirement. Low-protein diets have not been found to be efficacious in children with CKD, in achieving normal growth, or in slowing disease progression. Adult nephrologists caring for children and adolescents may be challenged by the existing complexities in identifying and interpreting nutritional status and growth in children. Pediatric nephrologists may face situations that call for a sound knowledge of assessing nutritional status and providing nutrition therapy for adolescents and young adults. This article discusses the differences in the assessment of nutritional status between children and adults, as well as provides a comprehensive approach to nutritional management for CKD across the age spectrum. Semin Nephrol 43:x-xx © 2023 Elsevier Inc. All rights reserved.

Diet and Physical Activity in Adult Dominant Polycystic Kidney Disease: A Review of the Literature

Autosomal polycystic kidney disease is the most common inherited kidney disease determining 5% of all end-stage kidney disease. The only therapy approved for this condition is Tolvaptan, which, with its aquaretic effect, has a strong effect on patients' daily life. Recently, the literature has been enriched with new works that analyze possible non-pharmacological therapeutic strategies to slow cysts' enlargement and chronic kidney disease progression. Among them, dietary schemes reducing carbohydrate intake and inducing ketoses have been demonstrated to have efficacy in several pre-clinical and clinical studies. A ketogenic diet, calorie restriction, intermittent fasting, and time-restricted feeding can reduce aerobic glycolysis and inhibit the mTOR pathway, producing a reduction in cyst cell proliferation, a reduction in kidney volume, and helping to preserve kidney function. ADPKD's burden of disease has an impact on patients' quality of life, and the possibility to play sports or carry out physical exercise can help people in everyday life. The multisystemic character of the disease, especially cardiovascular involvement, needs to be carefully evaluated to establish the quality and quantity of physical activity that patients can safely carry out.

The 2020 Updated KDOQI Clinical Practice Guidelines for Nutrition in Chronic Kidney Disease

Over the last 2 decades, there has been a great accumulation of new evidence regarding the management of nutritional and metabolic aspects of kidney disease. The 2020 update to the KDOQI Clinical Practice Guideline for Nutrition in CKD provides a comprehensive up-to-date information on the understanding and care of patients with CKD. It provides updated information on nutritional aspects of kidney disease for the practicing clinician and allied health-care workers. The current manuscript provides an overview of the updated guideline statements on major subjects including nutritional assessment, dietary protein and energy intake, nutritional supplementation, micronutrients, and electrolytes. The guidelines are focused on dietary management rather than all possible nutritional interventions.