Anti‐desmoglein‐2 autoantibodies do not discriminate between UK boxer dogs with and without arrhythmogenic right ventricular cardiomyopathy

Background Evidence regarding the diagnostic utility of serum anti‐desmoglein‐2 (DSG2) autoantibodies for arrhythmogenic right ventricular cardiomyopathy (ARVC) in boxer dogs is conflicting. Methods Prospective standardised evaluation of apparently healthy boxer dogs for ARVC was performed at three referral centres, including blood pressure measurement, electrocardiography, echocardiography, haematology, biochemistry (including cardiac troponin I) and 24‐hour Holter monitoring. Additional dogs with a diagnosis of ARVC were retrospectively recruited. ARVC disease status was defined using cut‐offs of 20 or less (unaffected) and more than 300 (affected) ventricular premature complexes of right ventricular origin in 24 hours. The residual serum samples were stored at ‒80°C for analysis for anti‐DSG2 autoantibodies using ELISA techniques. Results Forty boxer dogs were enrolled (11 healthy controls, 10 with preclinical ARVC and 19 with clinical ARVC). Serum anti‐DSG2 autoantibodies were detected in all dogs, bar one healthy dog. DSG2 differed significantly between groups ( p = 0.031) and was significantly lower in dogs with preclinical versus clinical ARVC ( p = 0.025). Limitations Some data were collected retrospectively, and some dogs were receiving antiarrhythmic therapy. Conclusion Serum DSG2 autoantibodies can be present in boxer dogs with preclinical and clinical ARVC and apparently healthy controls.