Open AccessEvaluation of Baseline Cortisol, Endogenous ACTH , and Cortisol/ ACTH Ratio to Monitor Trilostane Treatment in Dogs with Pituitary‐Dependent Hypercortisolism
Author(s) -
Burkhardt W.A.,
Boretti F.S.,
Reusch C.E.,
SieberRuckstuhl N.S.
Publication year - 2013
Publication title -
journal of veterinary internal medicine
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.356
H-Index - 103
eISSN - 1939-1676
pISSN - 0891-6640
DOI - 10.1111/jvim.12111
Subject(s) - medicine , adrenocorticotropic hormone , hydrocortisone , endocrinology , endogeny , baseline (sea) , hormone , biology , fishery
Background The effectiveness of trilostane treatment is currently monitored by regular ACTH stimulation tests, which are time‐consuming and expensive. Therefore, a monitoring system without a stimulation protocol and with less client expense would be preferable. Hypothesis/Objectives The aim of our study was to evaluate if baseline cortisol, endogenous ACTH ( ACTH ) concentration or the baseline cortisol to ACTH ratio (cortisol/ ACTH ratio) could replace the ACTH stimulation test. Animals Forty trilostane‐treated dogs with pituitary‐dependent hypercortisolism ( PDH ) were included in this prospective study. Methods A total of 148 ACTH stimulation tests and 77 ACTH concentrations and cortisol/ ACTH ratios were analyzed. Control of cortisol release was classified according to cortisol concentration after ACTH administration as excessive (<1.5 μg/dL; group 1), adequate (1.5–5.4 μg/dL; group 2), or inadequate (>5.4 μg/dL; group 3). Results Baseline cortisol concentrations had considerable overlap between excessively, adequately, and inadequately controlled dogs. Only baseline cortisol >4.4 μg/dL (in 12% of tests) was a reliable diagnosis of inadequate control. Endogenous ACTH concentrations did not differ between groups. The overlap of the cortisol/ ACTH ratio between groups was large. Correct classification was only possible if the cortisol/ ACTH ratio was >15, which occurred in 4% of tests. Conclusions and Clinical Importance To monitor trilostane treatment the ACTH stimulation test cannot be replaced by baseline cortisol, ACTH concentration, or the cortisol/ ACTH ratio.