HP04 - Plasma Amino Acid Profiles in Dogs with Chronic Liver Disease

Abstract
Background: Dogs with hepatocutaneous syndrome (HCS) have plasma hypoaminoacidemia. The specificity of this finding among dogs with other chronic hepatopathies (CH) is unknown.

Hypothesis/Objectives: To compare plasma amino acid panels (PAA) from a retrospective cohort of dogs with HCS with PAA in dogs with non-HCS CH.

Animals: Forty client-owned dogs with CH.

Methods: Dogs undergoing hepatic biopsy for chronic serum liver enzyme elevations were recruited. Twelve dogs each with vacuolar hepatopathy or chronic inflammatory disease and 8 dogs with congenital vascular/biliary disease were enrolled. Eight cases of HCS with PAA were retrospectively enrolled. PAA analysis was done at the UC Davis Amino Acid Laboratory. PAA concentrations in the 4 groups were compared using one-way ANOVA and the Kruskal-Wallis test, followed by the Tukey Kramer HSD and Steel-Dwass test for post hoc analysis, respectively. To find a unique PAA pattern in dogs with HCS, Lasso regression analysis with AIC forward selection was performed.

Results: There was no difference in breed, age or sex among the 4 groups. Compared to non-HCS liver diseases, dogs with HCS had significantly lower concentrations of aspartic acid, threonine, serine, asparagine, glutamine, glycine, alanine, citrulline, methionine, lysine, histidine, arginine, and proline (P < 0.0019 after Bonferroni correction). The Lasso regression analysis revealed that low glutamine, glycine, citrulline, arginine and proline concentrations were characteristic of dogs with HCS.

Conclusions and Clinical Importance: Plasma hypoaminoacidemia does not occur in dogs with non-HCS CH. Determination of PAA is warranted as a noninvasive biomarker for diagnosis of HCS in dogs.