Abstract
IMPORTANCE: Serum feline pancreatic lipase (fPL) is used to diagnose pancreatitis, but interpretation is challenging because fPL may be affected by non-pancreatic disease, including reduced renal function. OBJECTIVE: To evaluate the association between chronic kidney disease (CKD) stage and serum fPL in cats and characterize how renal biomarkers relate to fPL. METHODS: This retrospective study evaluated medical records of cats presented to a secondary referral veterinary hospital between February 2024 and March 2025. Inclusion required same-day testing of complete blood count, serum biochemistry, blood gas analysis, urinalysis, serum fPL, and abdominal ultrasonography. CKD staging followed International Renal Interest Society guidelines using serum creatinine, urine specific gravity (USG), and ultrasonography. Nonparametric group comparisons were performed using the Kruskal-Wallis test, and associations between fPL and renal biomarkers were assessed using Spearman's correlation. RESULTS: fPL increased significantly with advancing CKD stage (p < 0.001). Furthermore, fPL was positively correlated with blood urea nitrogen (ρ = 0.516, p < 0.001), creatinine (ρ = 0.459, p < 0.001), and inorganic phosphorus (ρ = 0.312, p < 0.001). Additionally, fPL and USG exhibited an inverse correlation (ρ = -0.502, p < 0.001). Ionized calcium showed no correlation with fPL (ρ = 0.012, p = 0.898). CONCLUSIONS AND RELEVANCE: In this clinical cohort, higher CKD stage was associated with higher serum fPL. Because fPL alone is insufficient to diagnose pancreatitis and may increase with reduced renal function, mild-to-moderate fPL elevations in cats with CKD should be interpreted in the context of clinical signs and pancreatic imaging findings.