Diagnostic Performance of Plasma Uric Acid, Magnesium and Other Biochemical Parameters in the Diagnosis of Renal Insufficiency in Sea Turtles
Abstract
Biochemical parameters used to diagnose renal compromise in mammals (i.e., creatinine, blood urea nitrogen) lack utility in reptiles and birdsdue to differences in nitrogen metabolism and excretion.1,2 The occurrence of renal disease is well documented in reptiles; therefore, there is a need for diagnostically useful biochemical parameters to diagnose renal insufficiency.3 The objective of this study was to assess and compare the diagnostic performance of plasma concentrations of albumin, blood urea nitrogen, calcium, chloride, magnesium, phosphorus, potassium, sodium, total protein and uric acid for the diagnosis of renal insufficiency in sea turtles. Twenty-four sea turtles with renal disease confirmed by histopathology and 42 sea turtles with no histologic evidence of renal disease, from four different sea turtle rehabilitation facilities, hospitalized between April 2004 and June 2012 were included in the study. Receiver operator characteristic (ROC) curve analysis was used to assess and compare the diagnostic performance of all biochemical parameters. In this study, the diagnostic performance of uric acid was superior to other biochemical parameters. The ROC area under the curve for uric acid was 0.861 (95% confidence interval 0.746 to 0.799). The estimated sensitivity and specificity when using uric acid were 72% and 90%, respectively. Magnesium had a sensitivity and specificity of 50% and 95%, respectively. The results demonstrate that evaluation of plasma uric acid and magnesium concentrations can be useful in the diagnosis, monitoring and prognosis in sea turtles affected by renal insufficiency.
Acknowledgments
This work was conducted with authorization of the Florida Fish and Wildlife Conservation Commission (MTP #12-021) and IACUC # 201106823. We thank the staff, volunteers and veterinarians at the Georgia Sea Turtle Center, the New England Aquarium, the Virginia Aquarium, the South Carolina Aquarium and members of the Sea turtle stranding and salvage network for support with recovery and medical care of the sea turtles. We are grateful to Kerry McNally, Shannon Pederson and Melannie Bachman for their help with data retrieval from medical records and shipment of samples to the University of Florida.
* Presenting author
Literature Cited
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