Association of folate concentrations with clinical signs and laboratory markers of chronic enteropathy in dogs

BACKGROUND: Serum folate is considered a biomarker of chronic enteropathy (CE) in dogs, but few studies have examined associations with markers of CE. HYPOTHESIS/OBJECTIVES: To evaluate serum folate concentrations in dogs with and without CE and associations with sample hemolysis and selected markers of CE. We hypothesized that hypofolatemia would be more common in dogs with CE and associated with hypocobalaminemia, higher CIBDAI, and hypoalbuminemia. ANIMALS: Six hundred seventy‐three dogs with available serum folate measurements performed at an academic veterinary hospital between January 2016 and December 2019. METHODS: Medical records were retrospectively reviewed to categorize cases as CE or non‐CE and record clinical details and laboratory markers. Relationships between serum folate, cobalamin, and CE variables were assessed using chi‐square, Kruskal‐Wallis, or Spearman's correlation tests. RESULTS: Of the 673 dogs, 99 CE were compared to 95 non‐CE. In the overall cohort, serum folate concentration did not correlate with sample hemolysis (P = .75). In the CE subset, serum folate and cobalamin concentrations were positively associated (rho = 0.34, FDR = 0.02). However, serum folate concentrations (median [25th, 75th percentiles]) were higher (CE: 12.1 (8.9, 16.1), non‐CE: 10.4 (7.2, 15.5); P = .04) and cobalamin concentrations were lower (CE: 343 (240, 597), non‐CE: 550 (329, 749); P = .001) in the CE vs non‐CE group. Serum folate was not associated with markers of CE, but serum cobalamin was associated with albumin (P = .04) and cholesterol (P = .03). CONCLUSIONS AND CLINICAL IMPORTANCE: Hypofolatemia is an inferior biomarker of CE compared to hypocobalaminemia.