383 Feeding dogs and cats with renal disease: What do we really know.

Abstract

Dietary management of renal disease involves restricting protein, phosphorus, and sodium in the diet while enhancing the levels of water-soluble vitamins and the long-chain omega-3 polyunsaturated fatty acids, eicosapentaenoic acid (EPA). Recent evidence supports the avoidance of high phosphorus intake in older dogs and cats, even before overt biochemical or clinical signs of renal disease are present. Animals with decreased tubular function as indicated by loss of urine concentration, elevated serum symmetric dimethylarginine (SDMA), and evidence of structural changes on imaging studies, with or without elevations in creatinine, should be fed a diet with a dietary phosphorus level at or below the National Research Council (NRC) minimum requirement for an adult dog or cat. For animals with glomerular disease, loss of plasma proteins (such as albumin) into the urine can result in progressive renal tubular damage. The degree of proteinuria is exacerbated with increased protein intake. The dietary treatment for this form of renal disease involves a reduction of dietary protein intake to the NRC recommended minimum, which will help decrease glomerular capillary pressure and subsequently lessen proteinuria. Dogs can become hyperkalemic as a function of progressive renal disease or secondary to medications, such as the ACE inhibitors enalapril and benazapril, and potassium restriction may be required to prevent potentially fatal hyperkalemic cardiac arrhythmias. Conversely, cats with renal disease often have enhanced loss of potassium through their urine and coupled with poor overall dietary intake may require potassium supplementation as clinical hypokalemia can result in constipation and generalized muscle weakness. Imbalance in orexigenic compounds, such as ghrelin, and anorexigenic compounds, such as cholecystokinin, can also occur with advanced uremia resulting in dysregulation of food intake and progressive cachexia. Appetite stimulants or placement of a feeding tube may be required to deliver optimal nutritional support with advanced renal failure.