Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2018 May;32(3):967-977.
doi: 10.1111/jvim.15079. Epub 2018 Mar 2.

Evaluation of individual low-dose dexamethasone suppression test patterns in naturally occurring hyperadrenocorticism in dogs

Michael Bennaim  1 , Robert E Shiel  1 , Christopher Forde  1 , Carmel T Mooney  1
Affiliations

Evaluation of individual low-dose dexamethasone suppression test patterns in naturally occurring hyperadrenocorticism in dogs

Michael Bennaim et al. J Vet Intern Med. 2018 May.

Abstract

Background: Dogs with hyperadrenocorticism (HAC) may be more mildly affected at the time of diagnosis today, which could influence the prevalence of associated clinical and clinicopathological abnormalities and diagnostic test performance. Different low-dose dexamethasone suppression test (LDDST) result patterns have not been evaluated individually.

Objectives: To assess the current features of HAC and evaluate if the diagnostic test performance of individual LDDST result patterns differ.

Animals: One hundred and twenty-three dogs undergoing investigation for HAC.

Methods: Retrospective evaluation of dogs in which a LDDST was performed and HAC confirmed or excluded by alternative means. Cases with basal cortisol concentrations (t0 ) < 1 μg/dL were excluded. Each LDDST result was classified as (a) complete suppression (t3 and t8 < 1 μg/dL), (b) lack of suppression (t3 and t8 > 1 μg/dL and both > 50% t0 ), (c) partial suppression (t3 and t8 > 1 μg/dL but either < 50% t0 ), (d) escape (t8 > 1 μg/dL and t3 < 1 μg/dL) or (e) inverse (t3 > 1 μg/dL and t8 < 1 μg/dL) pattern.

Results: Fifty-nine (48%) dogs were diagnosed with HAC and 64 (52%) with non-adrenal illness. Hyperadrenocorticism cases had similar clinicopathological abnormalities compared to previous reports. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) (95% confidence interval [CI]) of the LDDST for diagnosing HAC were 96.6 (91.9-100)%, 67.2 (55.7-78.7)%, 73.1 (63.2-82.9)%, and 95.6 (89.5-100)%, respectively. Lack of suppression pattern had the highest PPV (93.9 [85.8-100]%) followed by the partial suppression pattern (67.9 [50.6-85.2]%) and escape or inverse pattern (36.8 [15.1-58.5]%).

Conclusions and clinical importance: A lack of suppression LDDST pattern has the highest PPV for diagnosing HAC followed by a partial suppression pattern. By contrast, the escape or inverse pattern provided limited support of HAC.

Keywords: Cushing's syndrome; adrenal cortex; adrenal function test; canine; endocrinology; pituitary.

PubMed Disclaimer

Figures

Figure 1
Figure 1
A flow chart showing the selection of cases included in the study and the repartition of the different low‐dose dexamethasone suppression test patterns in each group
See this image and copyright information in PMC

References

    1. Behrend EN, Kooistra HS, Nelson R, et al. Diagnosis of spontaneous canine hyperadrenocorticism: 2012 ACVIM consensus statement (small animal). J Vet Intern Med. 2013;27:1292–1304. - PubMed
    1. Behrend EN, Kemppainen RJ, Clark TP, et al. Diagnosis of hyperadrenocorticism in dogs: a survey of internists and dermatologists. J Am Vet Med Assoc. 2002;220:1643–1649. - PubMed
    1. Reusch CE, Feldman EC. Canine hyperadrenocorticism due to adrenocortical neoplasia. Pretreatment evaluation of 41 dogs. J Vet Intern Med. 1991;5:3–10. - PubMed
    1. Kaplan AJ, Peterson ME, Kemppainen RJ. Effects of disease on the results of diagnostic tests for use in detecting hyperadrenocorticism in dogs. J Am Vet Med Assoc. 1995;207:445–451. - PubMed
    1. Gieger TL, Feldman EC, Wallack ST, Dank G. Lymphoma as a model for chronic illness: effects on adrenocortical function testing. J Vet Intern Med. 2003;17:154–157. - PubMed

LinkOut - more resources