Protein Biomarkers in Serum and Urine for Determining Presence or Absence of Hip Dysplasia in a Canine Model.

This study compares serum and urine concentrations of relevant protein biomarkers among adult dogs with or without radiographic canine hip dysplasia (CHD). Adult (≥ 2 years of age), client-owned dogs (n = 74) radiographically categorized as having at least "good" hips (n = 49) or having "mild", "moderate", or "severe" hip dysplasia (n = 25) by the Orthopedic Foundation for Animals (OFA). Urine and serum samples were obtained from each dog at a single time-point and processed and analyzed for relevant protein biomarkers. Urinary concentrations of CTX-II (p < 0.001) and TIMP-1 (p = 0.002) were significantly lower in dogs with CHD compared to dogs with no CHD. ROC curve analyses were successful in establishing a panel of 4 biomarkers (urinary CTX-I and II, serum MMP-9, and serum PIICP) with high discriminatory capability for the presence or absence of hip dysplasia in adult dogs (AUC = 0.89. Urine and serum biomarkers can distinguish adult dogs with radiographic CHD from those with no CHD with a sensitivity of 0.95 and specificity of 0.77 using ROC analysis with AUC 0.89. Clinical significance: This finding suggests that this simple, minimally invasive diagnostic technique has potential for discriminating dysplastic dogs from dogs with normal hips, with possible translational application to humans based on similar etiopathogenesis. This article is protected by copyright. All rights reserved.