2017 ACVIM Forum Research Abstract Program

Testing was prospectively performed in dogs suspected of hypoadrenocorticism. Dogs suspected of having hypoadrenocorticism received 1 mcg/kg cosyntropin IV followed four hours later by 5 mcg/kg cosyntropin IV. Preliminary studies confirmed the validity of performing two ACTH stimulation tests on the same day. Blood samples were obtained pre-and one hour post-ACTH for each dose (4 measurements total). Cortisol was measured using a previously validated radioimmunoassay. To detect differences in cortisol concentration between cosyntropin doses (1 and 5 mcg/kg) and between time points (baseline and 60-minutes), data were analyzed using a paired t-test and equivalence testing by commercial statistical computer programs. Significance was set at the P ≤ 0.05 level.