Evaluation of Serum 3‐Bromotyrosine Concentrations in Dogs with Steroid‐Responsive Diarrhea and Food‐Responsive Diarrhea

• Published in: Journal of veterinary internal medicine Vol. 31; no. 4; pp. 1056 - 1061
• Main Authors: Sattasathuchana, P., Allenspach, K., Lopes, R., Suchodolski, J.S., Steiner, J.M.
• Format: Journal Article
• Language: English
• Published: United States John Wiley and Sons Inc 01-07-2017
• Subjects: Activated eosinophil; Adrenal Cortex Hormones - therapeutic use; Animals; Canine; Case-Control Studies; Chronic enteropathy; Dog Diseases - blood; Dog Diseases - diet therapy; Dog Diseases - drug therapy; Dogs; Female; Gas Chromatography-Mass Spectrometry - veterinary; Male; Prospective Studies; SMALL ANIMAL; Treatment Outcome; Tyrosine - analogs & derivatives; Tyrosine - blood; Activated eosinophil; Chronic enteropathy; Canine
• ISSN: 0891-6640; 1939-1676
• DOI: 10.1111/jvim.14742

Background
The clinical usefulness of serum 3‐BrY concentrations for subclassifying dogs with food‐responsive diarrhea (FRD) and steroid‐responsive diarrhea (SRD) has not been studied.
Hypothesis/Objectives
To compare serum 3‐BrY concentrations in dogs with FRD, dogs with SRD, and healthy control dogs.
Animals
38 dogs with FRD, 14 dogs with SRD, and 46 healthy dogs.
Methods
Prospective study. Measurement of 3‐BrY concentration in serum samples was performed by gas chromatography/mass spectrometry.
Results
There was no association of peripheral eosinophilia in dogs with FRD, SRD, and healthy control dogs (P = 0.069). There was no significant correlation between peripheral eosinophil counts and serum 3‐BrY concentrations (ρ = −0.15, P = 0.13). Serum 3‐BrY concentrations in dogs with SRD (median [range] = 3.27, 0.9–26.23 μmol/L) were significantly higher than in dogs with FRD (median [range] = 0.99, 0.62–8.82 μmol/L; P = 0.007) or in healthy dogs (median [range] = 0.62, 0.62–1.79 μmol/L; P < 0.001). Also, serum 3‐BrY concentrations in dogs with FRD were significantly higher than in healthy dogs (P = 0.025). There was no significant correlation between the canine chronic enteropathy clinical activity index and serum 3‐BrY concentrations (ρ = 0.17, P = 0.23).
Conclusions and Clinical Importance
Measurement of serum 3‐BrY concentrations, but not the peripheral eosinophil count, is helpful for detecting dogs with SRD and FRD.