Correlation between separate findings in 60 dogs suffering from CKD in IRIS stage 1

Abstract Background The International Renal Interest Society (IRIS) reports guidelines for classification and therapy for dogs suffering from chronic kidney disease (CKD). Dogs in stage 1 show no elevated serum creatinine, but some other sign of kidney disease like elevated Symmetric Dimethylarginin (SDMA), proteinuria, low urine specific gravity or abnormalities in the sonography of the kidneys. Objective of this study was to access the correlation between inclusion criteria and to give an estimation whether a more detailed staging or a substaging for patients with elevated SDMA levels might be useful regarding possible treatment recommendations. Results Sixty patients in IRIS stage 1 were included into the study. Most of these dogs were included due to raised SDMA level (n=22) or sonographic abnormalities of the kidneys (n=16). In order to rank and compare results of ultrasonography, a sonography score was developed. Additionally, results from blood work, urinalysis, ultrasonography and in some cases glomerular filtration rate (GFR) were examined. Correlation analysis showed positive correlation between creatinine and urea and negative correlation between creatinine and urinary protein-to-creatinine ratio (Up/c). Between SDMA, phosphate, urine specific gravity and sonographic findings there is no dependency with any other examined parameter. Conclusion Results showed that patients in IRIS stage 1 are a heterogeneous group and giving precise treatment recommendation might be challenging. If future studies will suggest treatment in this stage of CKD, such as renal diet, a more detailed classification is needed.