Nutrition has a fundamental role in the management of kidney patients, acute and chronic, on conservative or on substitutive dialysis treatment or after kidney transplantation. In chronic kidney disease (CKD), independently from the cause of the original renal damage there is a progressive and irreversible loss of nephrons and organ function leading to the final stages of kidney failure (ESRD) when dialysis treatment needs to be started. Some nutritional intervention may be useful to prevent or delay the development of kidney disease associated with some chronic conditions such as overweight (leading to Obesity-related glomerulopathy, ORG), diabetes mellitus. or hypertension or to delay the progression toward the end stages of kidney disease. In later stages of CKD, dietary modifications (protein, phosphate, calcium, potassium and sodium) are part of the management of some uremic complications. Since protein-energy malnutrition (PEM) is a common finding in CRF and its presence at the beginning of dialysis caries a bad prognosis, with higher mortality and complication rates, the nutritional status of the patient needs to be constantly monitored and every effort should be taken be prevented or to control malnutrition. In patients with CRF the rationale, the goals and the modalities of nutritional prescriptions change with the degree of loss of renal function, the etiology of kidney disease, the nutritional status of the subjects, the presence and the severity of clinical complications or co-morbidities and the need for dialysis treatment. When CRF patients start substitutive treatment the nutritional requirements change considerably. The big challenge for the nutritionist is to preserve the nutritional status, threatened by chronic nutrient losses and catabolism induced by dialysis, while at the same time controlling some of the symptoms not corrected by the dialysis sesions. Acute kidney failure(ARF) is associated with an acute type of PEM and nutritional interventions are generally similar to those for the acute hypercatabolic patients, with normal renal function.. In acute kidney patients however special substrates may be useful. Finally kidney transplant subjects require special care to counteract the effects on the nutritional status and nutrient requirements at first from the surgery and later from the post-transplant drug treatment.
