Significance of Symmetric Dimethylarginine in Evaluating Renal Insufficiency in Rehabilitated Wild Florida Manatees (Trichechus manatus latirostris)
Renal compromise is a significant complication when rehabilitating debilitated, wild Florida manatees (Trichechus manatus latirostris). Many animals present malnourished, dehydrated, and may have sustained direct trauma to the kidneys via boat strikes or ischemic events. Clinicians are limited to analysis of serum urea nitrogen, creatinine levels, and urinalysis (if urine can be obtained) to determine the extent of renal insufficiency, which may not accurately reflect renal function like it does in other species. Serum creatinine has been shown to be significantly affected by outside factors such as food intake, food type, and environmental water salinity in Florida manatees.3 This poses a diagnostic challenge for clinicians in discerning how paramount renal compromise is to the animal's overall health and prognosis.
Symmetric dimethylarginine (SDMA) is proven to be an accurate measure of glomerular filtration rate, and has shown to be a reliable biomarker for early detection and monitoring of chronic kidney disease in humans, cats, and dogs.1,2,4 We retrospectively evaluated SDMA values in a population of ten wild Florida manatees at a rehabilitation facility whose post-mortem evaluations (including gross necropsy and/or histology) revealed renal damage. We compared these values to six wild Florida manatees without evidence of renal impairment on post-mortem exam to determine statistical significance. Preliminary data revealed a positive correlation between serum creatinine and SDMA, which we hypothesize indicates clinical utility of SDMA for renal compromise in manatees. This study was pursued to determine the diagnostic value of SDMA in wild Florida manatees undergoing rehabilitation.
The authors wish to thank the Tampa's Lowry Park Zoo veterinary team members, including Michelle Devlin, Heather Henry, and Ryan O'Shea; the Florida Mammals keeper staff; and Martine de Wit and the staff at the Florida Fish and Wildlife Conservation Commission Marine Mammal Pathology Laboratory.
* Presenting author
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