Nutrition and chronic renal failure

Clinical symptoms of renal dysfunction (polydipsia, polyuria) are not evident until a large portion of renal tissue has been destroyed. Until this point, many cases can be undiagnosed. Chronic renal failure has many physiological effects. These include the decreased ability to excrete nitrogenous waste (and thus build up of azotaemia), sodium and phosphorus, and an increased loss of potassium and water-soluble vitamins. Other clinical symptoms also include systemic hypertension, secondary hyperparathyroidism and nonregenerative anaemia (Lane, 2005).

Most veterinary practices offer owners renal screening for older patients, as part of senior clinics or as part of preanaesthetic screening or before the start of pharmaceutical regimes (normally osteoarthritis treatments). Early identification of these cases is required to manage the different stages of chronic renal failure. Guidelines set out by the International Renal Interest Society (IRIS, 2019) help to establish which types of management are required at the different disease stages.