title: Routine kidney variables, glomerular filtration rate and urinary cystatin C in cats with diabetes mellitus, cats with chronic kidney disease and healthy cats.
abstract: OBJECTIVE
  Diabetic kidney disease (DKD) is a frequent and serious complication in human diabetic patients, but data are limited in cats. This study was undertaken to assess whether diabetic cats are susceptible to DKD.
  
  
  METHODS
  Kidney function was compared between 36 cats with diabetes mellitus (DM), 10 cats with chronic kidney disease (CKD) and 10 age-matched healthy cats by measuring routine kidney variables (serum creatinine [sCreat], serum urea [sUrea], urine specific gravity [USG], urinary protein:creatinine ratio [UPC]), urinary cystatin C:creatinine ratio and glomerular filtration rate (GFR). Urinary cystatin C (uCysC) was measured with a human particle-enhanced nephelometric immunoassay, validated to measure feline cystatin C, in all but two diabetic cats. GFR was evaluated by exo-iohexol clearance in 17 diabetic cats, all cats with CKD and all healthy cats.
  
  
  RESULTS
  Diabetic cats had significantly (mean ± SD) lower sCreat (123 ± 38 vs 243 ± 80 µmol/l), sUrea (11 ± 3 vs 18 ± 7 mmol/l) and urinary cystatin C:creatinine ratio (6 ± 31 vs 173 ± 242 mg/mol), and a significantly higher USG (1.033 ± 0.012 vs 1.018 ± 0.006) and GFR (2.0 ± 0.7 vs 0.8 ± 0.3 ml/min/kg) compared with cats with CKD. Compared with healthy cats, diabetic cats only had significantly lower USG (1.033 ± 0.012 vs 1.046 ± 0.008). Proteinuria (UPC >0.4) was present in 39% of diabetic cats, in 30% of cats with CKD and in none of the healthy cats. However, the UPC did not differ statistically between the three groups.
  
  
  CONCLUSIONS
  Based on evaluation of routine kidney variables, GFR and uCysC as a tubular marker at a single time point, a major impact of feline DM on kidney function could not be demonstrated.
authors.affiliation: Department of Small Animal Medicine and Clinical Biology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium dominique.paepe@ugent.be.
authors.forename: Dominique
authors.initials: D
authors.lastname: Paepe
authors.affiliation: Department of Small Animal Medicine and Clinical Biology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
authors.forename: Liesbeth Fe
authors.initials: LF
authors.lastname: Ghys
authors.affiliation: Department of Small Animal Medicine and Clinical Biology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
authors.forename: Pascale
authors.initials: P
authors.lastname: Smets
authors.affiliation: University of Toulouse, INP, National Toulouse Veterinary School, Clinical Research Unit, Toulouse, France.
authors.forename: Hervé P
authors.initials: HP
authors.lastname: Lefebvre
authors.affiliation: Department of Pharmacology, Toxicology and Biochemistry, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
authors.forename: Siska
authors.initials: S
authors.lastname: Croubels
authors.affiliation: Department of Small Animal Medicine and Clinical Biology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
authors.forename: Sylvie
authors.initials: S
authors.lastname: Daminet
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000097:blood / Q000652:urine; D001806:Blood Urea Nitrogen; D002371:Cat Diseases / Q000097:blood* / Q000652:urine*; D002415:Cats; D003404:Creatinine / Q000097:blood; D055316:Cystatin C / Q000652:urine*; D003920:Diabetes Mellitus / Q000662:veterinary*; D005919:Glomerular Filtration Rate; D007677:Kidney Function Tests / Q000662:veterinary; D012016:Reference Values; D051436:Renal Insufficiency, Chronic / Q000662:veterinary*
chemical_list: D015415:Biomarkers; D055316:Cystatin C; D003404:Creatinine