Assessment of Coagulation and Potential Biochemical Markers for Hypercoagulability in Canine Hyperadrenocorticism

Background Anecdotal accounts and limited research suggest that dogs with spontaneous hyperadrenocorticism ( HAC ) are at risk of developing thromboembolic complications. Detailed description of coagulation status and identification of subsets of dogs at greatest risk would impact therapeutic recommendations for these patients. Hypothesis/Objectives Hypothesis: A subset of dogs with HAC will have a hypercoagulable tendency as identified by increased procoagulant activity, decreased fibrinolysis, or both. Objective 1: To document the existence of this hypercoagulable tendency in HAC dogs using assays of individual coagulation factors, fibrinolytic activity, and systemic coagulation. Objective 2: To evaluate clinical and biochemical markers in HAC dogs to identify a subset of HAC patients at increased risk of this hypercoagulable tendency. Animals Seventeen dogs newly diagnosed with HAC . Methods Prospective study. Medical history, physical examination findings, routine diagnostic tests, and comprehensive coagulation testing were performed at the time of HAC diagnosis. Coagulation parameters were assessed individually and as panels for each dog. Historical and clinical variables were correlated with coagulation parameters to identify risk factors. Results The majority (88.2%) of HAC dogs exhibited a hypercoagulable tendency. Abnormalities in 1 coagulation assay did not predict abnormalities in others. Duration of clinical signs of HAC did not predict hypercoagulability. Comorbid conditions or abnormal clinicopathologic parameters that predicted hypercoagulability were not identified. Conclusions and Clinical Importance Although HAC dogs may demonstrate a hypercoagulable tendency individually and as a group, comorbid conditions or biochemical variables that would predict more severe coagulation abnormalities were not identified.