Evaluation of and the prognostic factors for cats with big kidney-little kidney syndrome.

Abstract

BACKGROUND: The term big kidney-little kidney syndrome in cats has been used for many years, but the definitions are not consistent and relevant research is limited. OBJECTIVE: To determine the factors that differ between normal and BKLK cats, as well as to develop models for predicting the 30-day survival of cats with ureteral obstruction (UO). ANIMALS: Sixteen healthy cats and 64 cats with BKLK. METHODS: Retrospective study. To define BKLK by reference to data from clinically healthy cats. The demographic and clinicopathological data among groups were statistically analyzed. RESULTS: Big kidney-little kidney syndrome cats had higher blood urea nitrogen (BUN) (median [interquartile range] 69 [28-162] vs 21 [19-24]&#xa0;mg/dL, P&#x2009;<&#x2009;.001), creatinine (5.6 [1.9-13.3] vs 1.3 [1.05-1.40]&#xa0;mg/dL, P&#x2009;<&#x2009;.001), and white blood cells (10&#xa0;800 [7700-17&#x2009;500] vs 6500 [4875-9350] /&#x3bc;L, P&#x2009;<&#x2009;.001) and lower hematocrit (32.8 [27.1-38.4] vs 39.1 [38.1-40.4]%, P&#x2009;<&#x2009;.001), urine specific gravity (1.011 [1.009-1.016] vs 1.049 [1.044-1.057], P&#x2009;<&#x2009;.001) and pH (5.88 [5.49-6.44] vs 6.68 [6.00-7.18], P&#xa0;=&#xa0;.001) compared to the control cats. A lower body temperature (BT; 38.1 [37.9-38.2] vs 38.7 [38.3-39.2]&#xb0;C, P&#xa0;=&#xa0;.009), higher BUN (189 [150-252] vs 91 [36-170]&#xa0;mg/dL, P&#xa0;=&#xa0;.04), and creatinine (15.4 [13.3-17.4] vs 9.0 [3.1-14.2]&#xa0;mg/dL, P&#xa0;=&#xa0;.03) were found among the UO cats that were not 30-day survivors. A combination of BUN, phosphorus, and BT can predict 30-day survival among UO cats with an area under receiver operating characteristic curve of 0.863. (P&#xa0;=&#xa0;.01). CONCLUSION: An increase in the length difference between kidneys can indicate UO, but cannot predict outcome for BKLK cats.