Presented in part as oral abstract at the 18th Annual European College of Veterinary Internal Medicine Forum, Ghent, Belgium 2008.
Urinary Catecholamine and Metanephrine to Creatinine Ratios in Dogs with Hyperadrenocorticism or Pheochromocytoma, and in Healthy Dogs
Article first published online: 12 AUG 2010
Copyright © 2010 by the American College of Veterinary Internal Medicine
Journal of Veterinary Internal Medicine
Volume 24, Issue 5, pages 1093–1097, September/October 2010
How to Cite
Quante, S., Boretti, F.S., Kook, P.H., Mueller, C., Schellenberg, S., Zini, E., Sieber-Ruckstuhl, N. and Reusch, C.E. (2010), Urinary Catecholamine and Metanephrine to Creatinine Ratios in Dogs with Hyperadrenocorticism or Pheochromocytoma, and in Healthy Dogs. Journal of Veterinary Internal Medicine, 24: 1093–1097. doi: 10.1111/j.1939-1676.2010.0578.x
- Issue published online: 2 SEP 2010
- Article first published online: 12 AUG 2010
- Submitted February 22, 2010; Revised May 3, 2010; Accepted June 18, 2010.
- Adrenal gland;
- Cushing's syndrome;
Background: Urinary catecholamines and metanephrines are used for the diagnosis of pheochromocytoma (PHEO) in dogs. Hyperadrenocorticism (HAC) is an important differential diagnosis for PHEO.
Objectives: To measure urinary catecholamines and metanephrines in dogs with HAC.
Animals: Fourteen dogs with HAC, 7 dogs with PHEO, and 10 healthy dogs.
Methods: Prospective clinical trial. Urine was collected during initial work-up in the hospital; in dogs with HAC an additional sample was taken at home 1 week after discharge. Parameters were measured using high-pressure liquid chromatography and expressed as ratios to urinary creatinine concentration.
Results: Dogs with HAC had significantly higher urinary epinephrine, norepinephrine and normetanephrine to creatinine ratios than healthy dogs. Urinary epinephrine, norepinephrine, and metanephrine to creatinine ratios did not differ between dogs with HAC and dogs with PHEO, whereas the urinary normetanephrine to creatinine ratio was significantly higher (P= .011) in dogs with PHEO (414, 157.0–925.0, median, range versus (117.5, 53.0–323.0). Using a cut-off ratio of 4 times the highest normetanephrine to creatinine ratio measured in controls, there was no overlap between dogs with HAC and dogs with PHEO. The variables determined in urine samples collected at home did not differ from those collected in the hospital.
Conclusion and Clinical Importance: Dogs with HAC might have increased concentrations of urinary catecholamines and normetanephrine. A high concentration of urinary normetanephrine (4 times normal), is highly suggestive of PHEO.