A preliminary investigation into the prognostic relevance of symmetric dimethylarginine in critically ill dogs

Objective To determine if there is an association between the concentration of symmetric dimethylarginine (SDMA) in dogs measured at the time of admission with the severity of critical illness and short-term mortality. Design Setting This prospective observational study recruited critically ill dogs with heterogeneous diagnoses and then classified their disease severity using the acute patient physiologic and laboratory evaluation complete score as having either a good (<30) or poor (>= 30) prognosis. This study was conducted at Ross University Veterinary Clinic between January and November 2015. Animals Interventions After exclusion of dogs diagnosed with acute kidney injury, 22 critically ill dogs and 7 control dogs were included in the study. Each dog was assigned an acute patient physiologic and laboratory evaluation score calculated by the summation of individual scores allocated to selected clinical, focused assessment by sonography, hematological, and biochemistry results. Plasma SDMA concentrations were measured for all dogs at the time of admission. Measurement and Main Results Conclusion There was no difference identified in SDMA concentrations between dogs with a severe category of disease as compared to mild to moderate category, or critically ill dogs compared to control dogs. There was also no difference identified in SDMA concentrations in survivors as compared to nonsurvivors. Similarly, SDMA concentration was not higher in nonsurvivors than in survivors (P = 0.968). In this population of dogs, SDMA was not a prognostic indicator. Further work may be warranted in specific populations of animals but based upon this work SDMA is likely of little relevance.