EVALUATION OF PLASMA AMMONIA LEVELS IN DOGS WITH RENAL FAILURE IN UREMIC SYNDROME.

P. T. DIAS SILVA, M. M. KOGIKA, B. M. P. COELHO, V. A. B. F. WIRTHL, P. R. G. MONTEIRO, M. K. HAGIWARA

Abstract


Hyperammonemia in dogs is usually related to abnormalities of portal vascular system or hepatic failure; however, the increase of plasma ammonia levels is also reported in cases where the liver has no pathological processes. In humans, horses, dogs and rats, hyperammonemia has been described in cases of intestinal and urinary infections by urease-producing bacteria and renal failure in uremic syndrome as well. The uremic process and the acidosis seem to inhibit the hepatic enzymes responsible for ammonia biotransformation, whose accumulation could result in gastroenteritis, stomatitis and neurological problems. In this study, 26 uremic dogs with acute or chronic renal failure were studied. The most frequent clinical signs were emesis, melena, anorexia, halitosis and prostration. Means of blood pH, bicarbonate and base excess were 7.24, 12.2mEq/L and ?13.6, respectively, that showed tendency to acidosis. Mean of plasma ammonia levels was 2,147mg/dL, and the minimal and maximal levels observed were 580mg/dL and 4,680mg/dL, respectively. All these values were higher than those reported for healthy dogs. The results suggested that the measurement of ammonia plasma levels might give further information to the laboratory evaluation of patients with renal failure during uremic syndrome, therefore allowing a better understanding of the pathophysiology of hyperammonemia.
KEY-WORDS: Dogs. Ammonia. Uremia. Nephropathy.



DOI: http://dx.doi.org/10.15361/2175-0106.2005v21n4p116-120