Evaluation of serum 17-hydroxyprogesterone concentration after administration of ACTH in dogs with hyperadrenocorticism.
OBJECTIVE
To evaluate serum 17-hydroxyprogesterone (17-OHP) concentration measurement after administration of ACTH for use in the diagnosis of hyperadrenocorticism in dogs.


METHODS
Prospective study.


METHODS
110 dogs.


METHODS
Serum 17-OHP concentrations were measured before and after ACTH stimulation in 53 healthy dogs to establish reference values for this study. Affected dogs had pituitary-dependent (n = 40) or adrenal tumor-associated (12) hyperadrenocorticism or potentially had atypical hyperadrenocorticism (5; diagnosis confirmed in 1 dog). In affected dogs, frequency interval and borderline and abnormal serum 17-OHP concentrations after ACTH stimulation were determined. Serum cortisol concentrations were assessed via low-dose dexamethasone suppression and ACTH stimulation tests.


RESULTS
In healthy dogs, serum 17-OHP concentration frequency intervals were grouped by sex and reproductive status (defined as < 95th percentile). Frequency intervals of serum 17-OHP concentrations after ACTH stimulation were < 77, < 2.0, < 3.2, and < 3.4 ng/mL (< 23.3, < 6.1, < 9.7, and < 10.3 nmol/L) for sexually intact and neutered females and sexually intact and neutered males, respectively. In 53 dogs with confirmed hyperadrenocorticism, serum cortisol concentrations after ACTH stimulation and 8 hours after administration of dexamethasone and serum 17-OHP concentrations after ACTH stimulation were considered borderline or abnormal in 79%, 93%, and 69% of dogs, respectively. Two of 5 dogs considered to have atypical hyperadrenocorticism had abnormal serum 17-OHP concentrations after ACTH stimulation.


CONCLUSIONS
Serum 17-OHP concentration measurement after ACTH stimulation may be useful in the diagnosis of hyperadrenocorticism in dogs when other test results are equivocal.
Benitah
Noémi
N
Veterinary Medical Teaching Hospital, School of Veterinary Medicine, University of California, Davis, CA 95616, USA.
Feldman
Edward C
EC
Kass
Philip H
PH
Nelson
Richard W
RW
D019326:17-alpha-Hydroxyprogesterone / Q000097:blood*; D000308:Adrenocortical Hyperfunction / Q000097:blood / Q000175:diagnosis / Q000662:veterinary*; D000324:Adrenocorticotropic Hormone; D000818:Animals; D003907:Dexamethasone; D004283:Dog Diseases / Q000097:blood / Q000175:diagnosis*; D004285:Dogs; D005260:Female; D005938:Glucocorticoids; D006854:Hydrocortisone / Q000097:blood; D008297:Male; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012680:Sensitivity and Specificity
D005938:Glucocorticoids; D019326:17-alpha-Hydroxyprogesterone; D003907:Dexamethasone; D000324:Adrenocorticotropic Hormone; D006854:Hydrocortisone