Association between dietary factors and calcium oxalate and magnesium ammonium phosphate urolithiasis in cats

Objective-To identify dietary factors associated with the increase in occurrence of calcium oxalate (CaOx) uroliths and the decrease in occurrence of magnesium ammonium phosphate (MAP) uroliths in cats. Design-Case-control study. Animals-173 cats with CaOx uroliths, 290 cats with MAP uroliths, and 827 cats without any urinary tract diseases. Procedure-Univariate and multivariate logistic regression were performed. Results-Cats fed diets low in sodium or potassium or formulated to maximize urine acidity had an increased risk of developing CaOx uroliths but a decreased risk of developing MAP uroliths. Additionally, compared with the lowest contents, diets with the highest moisture or protein contents and with moderate magnesium, phosphorus, or calcium contents were associated with decreased risk of CaOx urolith formation, In contrast, diets with moderate fat or carbohydrate contents were associated with increased risk of CaOx urolith formation. Diets with the highest magnesium, phosphorus, calcium, chloride, or fiber contents and moderate protein content were associated with increased risk of MAP urolith formation. On the other hand, diets with the highest fat content were associated with decreased risk of MAP urolith formation. Conclusions and Clinical Relevance-Results suggest that diets formulated to contain higher protein, sodium, potassium, moisture, calcium, phosphorus, and magnesium contents and with decreased urine acidifying potential may minimize formation of CaOx uroliths in cats. Diets formulated to contain higher fat content and lower protein and potassium contents and with increased urine acidifying potential may minimize formation of MAP uroliths.