Comparison of Contrast Computed Tomography Renal Lesions and Uric Acid Values in Avian Cases.

Uric acid is commonly used for evaluation of kidney function in avian patients and may become significantly elevated with advanced renal disease, dehydration, or postprandially in carnivorous and piscivorous birds. Advanced imaging such as computed tomography (CT) has become notable in avian medicine for increased detail and precise information about patient anatomy and pathology. Avian orders examined included Psittaciformes, Bucerotiformes, Anseriformes, Pelecaniformes, and Accipitriformes. Iodinated intravenous contrast (370 mg/ml) was used at 4-6 ml/kg given over 2 minutes. All patients underwent pre-, during- and post-contrast scans. The 'during' scan was taken 30-60 seconds into contrast administration. A post-contrast scan was started after the completion of contrast delivery and the 'during' scan. Contrast studies allowed for kidney shape, size and position characterization and renal contrast uptake and clearance. Renal lesions identified on contrast CT include renomegaly, atrophy, cysts, hypoperfusion, mass invasion, and avulsion/trauma. At the time of submission, 47 avian cases met case inclusion criteria which included the CT protocol described above identifying renal lesions and uric acid values collected within 6 months prior to imaging. While the published normal values for uric acid range between species, we designated values greater than 12.0 mg/dl as hyperuricemic.2 Six of 47 cases had hyperuricemia. Of the 47 cases, 8/8 submitted for histopathology had confirmed renal disease with 2/8 of those cases having hyperuricemia. This study demonstrates poor correlation between hyperuricemia and renal lesions identified on contrast-based CT scans. [ABSTRACT FROM AUTHOR]