Presented in part as abstract at the 24th Annual Forum of the American College of Veterinary Internal Medicine, Louisville, KY, June 2006. [Brömel C, Nelson RW, Feldman EC, et al. Serum inhibin immunoreactivity in neutered dogs with adrenal dysfunction. J Vet Intern Med 2006;20:729 (abstract)]
Serum Inhibin Concentration in Dogs with Adrenal Gland Disease and in Healthy Dogs
Version of Record online: 11 JAN 2013
Copyright © 2012 by the American College of Veterinary Internal Medicine
Journal of Veterinary Internal Medicine
Volume 27, Issue 1, pages 76–82, January/February 2013
How to Cite
Brömel, C., Nelson, R.W., Feldman, E.C., Munro, C.J., Kass, P.H., Vico, A.E., Labelle, P. and Conley, A.J. (2013), Serum Inhibin Concentration in Dogs with Adrenal Gland Disease and in Healthy Dogs. Journal of Veterinary Internal Medicine, 27: 76–82. doi: 10.1111/jvim.12027
- Issue online: 11 JAN 2013
- Version of Record online: 11 JAN 2013
- Manuscript Accepted: 29 OCT 2012
- Manuscript Revised: 22 OCT 2012
- Manuscript Received: 10 FEB 2012
- Pituitary gland;
Studies in humans identified the synthesis and secretion of inhibin from adrenocortical tumors, but not pheochromocytoma (PHEO). Inhibin has not been examined in dogs as a serum biomarker for adrenal gland tumors.
To determine serum inhibin concentration in dogs with adrenal gland disease and in healthy dogs.
Forty-eight neutered dogs with adrenal disease including pituitary-dependent hyperadrenocorticism (PDH, 17), adrenocortical tumor (18), and PHEO (13), and 41 healthy intact or neutered dogs.
Prospective observational study. Dogs were diagnosed with PDH, adrenocortical tumor (hyperadrenocorticism or noncortisol secreting), or PHEO based on clinical signs, endocrine function tests, abdominal ultrasound examination, and histopathology. Inhibin concentration was measured by radioimmunoassay in serum before and after ACTH stimulation, and before and after treatment.
In neutered dogs, median inhibin concentration was significantly higher in dogs with adrenocortical tumors (0.82 ng/mL) and PDH (0.16 ng/mL) than in dogs with PHEO and healthy dogs (both undetectable). Median inhibin concentration was significantly higher in dogs with adrenocortical tumors than in those with PDH and decreased after adrenalectomy. Median inhibin concentration was significantly higher in intact than in neutered healthy dogs and was similar in pre- and post-ACTH stimulation. Sensitivity, specificity, and accuracy of serum inhibin concentration for identifying an adrenal tumor as a PHEO were 100, 88.9, and 93.6%, respectively.
Conclusions and Clinical Importance
Adrenocortical tumors and PDH but not PHEOs are associated with increased serum inhibin concentration; undetectable inhibin is highly supportive of PHEO in neutered dogs with adrenal tumors.