The effects of illness on urinary catecholamines and their metabolites in dogs.
BACKGROUND
Urinary catecholamines and metanephrines have been proposed as a diagnostic tool for identifying canine pheochromocytomas, but the effects of critical illness on urine concentrations of catecholamines and metanephrines currently are unknown.


OBJECTIVE
To examine the effects of illness on urine concentrations of catecholamines and metanephrines in dogs.


METHODS
Twenty-five critically ill dogs and 25 healthy age- and sex-matched control dogs.


METHODS
Prospective observational study. Urine was collected from healthy and critically ill dogs, and urine concentrations of epinephrine, norepinephrine, metanephrine, and normetanephrine were measured by high-performance liquid chromatography with electrochemical detection. Urinary catecholamine and metanephrine:creatinine ratios were calculated and compared between groups.


RESULTS
Urinary epinephrine, norepinephrine, metanephrine, and normetanephrine:creatinine ratios were higher in critically ill dogs when compared with a healthy control population (P=.0009, P<0.0001, P<0.0001, and P<0.0001, respectively).


CONCLUSIONS
Illness has a significant impact on urinary catecholamines and their metabolites in dogs. Further investigation of catecholamine and metanephrine concentrations in dogs with pheochromocytomas is warranted to fully evaluate this test as a diagnostic tool; however, the findings of this study suggest that the results may be difficult to interpret in dogs with concurrent illness.
Cameron
K N
KN
Department of Small Animal Clinical Sciences, Virginia-Maryland Regional College of Veterinary Medicine, Blacksburg, VA 24061, USA. kcameron@vt.edu
Monroe
W E
WE
Panciera
D L
DL
Magnin-Bissel
G C
GC
D000818:Animals; D016022:Case-Control Studies; D002395:Catecholamines / Q000378:metabolism / Q000652:urine*; D004283:Dog Diseases / Q000652:urine*; D004285:Dogs; D005260:Female; D008297:Male; D008676:Metanephrine / Q000378:metabolism / Q000652:urine; D011446:Prospective Studies
D002395:Catecholamines; D008676:Metanephrine