Cross-sectional characterization of renal function in cats with caudal stomatitis

Abstract

Objectives: The objective of the study was to compare renal functional biomarkers in cats and in caudal stomatitis (CS) and in age-matched control cats.

Methods: A cross-sectional, case-control study was conducted on 44 client-owned cats with CS that were prospectively enrolled and evaluated for a Comprehensive Oral Health Assessment and Treatment at one of four institutions. Renal function was assessed with measurement of serum creatinine, urea nitrogen, serum symmetric dimethylarginine, urinalysis, urine protein:creatinine ratio and urine protein electrophoresis. Affected gingiva was biopsied to confirm the diagnosis of stomatitis. Renal biochemical analyses from the experimental group were compared with those of 44 age-matched controls without CS enrolled prospectively or retrospectively after presenting to the primary institution for routine healthcare. Control cats were included if they were clinically stable, their chronic illnesses were well managed and minimal dental disease was present on examination. Renal biomarkers were compared between groups using a t-test or the Mann-Whitney U-test. Frequency of azotemia, proteinuria and the clinical diagnosis of renal disease were compared using Fisher's exact test.

Results: Relative to the control group, cats in the CS group had significantly lower serum creatinine (P <0.001) and albumin concentrations (P <0.001), urine specific gravity (P = 0.024) and hematocrit (P = 0.003), and higher serum phosphorus (P <0.001), potassium (P <0.001) and globulin concentrations (P <0.001), white blood cell count (P <0.001) and urine protein:creatinine ratio (P = 0.009). There were no significant differences in serum symmetric dimethylarginine or urea nitrogen concentrations. No clinically significant findings were noted on urine protein electrophoresis. There were no significant differences in the frequency of azotemia, proteinuria or renal disease categories between the two groups.

Conclusions and relevance: The present study does not demonstrate a significant difference in the frequency of kidney disease between cats with and without CS. Longitudinal evaluation is warranted to investigate the relationship between renal disease and CS.

Keywords: Caudal stomatitis; chronic kidney disease; renal dysfunction; stomatitis.

Figure 1

Box plot of (a) serum creatinine, (b) symmetric dimethylarginine (SDMA), (c) urea nitrogen, (d) phosphorus, (e) potassium, (f) albumin and (g) globulin concentrations, (h) hematocrit, (i) white blood cell count, (j) urine specific gravity and (k) urine protein:creatinine ratio in cats with caudal stomatitis (n = 44) and in age-matched cats without stomatitis (controls; n = 44). The number of cats for which data are available is noted on the x-axis. Boxes represent the interquartile range, and the horizontal bar within each box represents the median. Upper and lower bars and outliers (closed circles) are plotted using Tukey’s method. **P <0.01; ***P <0.001; ****P <0.0001