Serum total bile acid levels in canine dirofilariasis.

Abstract

The concentrations of serum total bile acids (SBA) were measured by the enzyme-fluorimetric method in 60 dogs with dirofilariasis classified into 4 groups based on the severity of the disease. The results obtained were as follows: the SBA levels in the serious (38.0nM±40.8 (S.D.), n=14) and hemoglobinuria (24.4nM±18.3, n=26) groups were significantly higher than in the normal (5.3nM±3.9, n=94), subclinical (9.0nM±9.3, n=9) and mild (7.3nM±6.8, n=11) groups. There were significant correlations between the SBA concentration and the results of several laboratory tests in all the 4 filariasis groups and 3 filariasis groups without hemoglobinuria. Moreover, a significant correlation was found between the SBA concentration and the lecithin cholesterol acyltransferase (LCAT) activity, and this seemed to be ascribable to the decreased LCAT production caused by liver injury rather than to the direct inhibition with bile acids. Despite the severe liver cell damage, the SBA level of the hemoglobinuria group was not as high as that of the serious group, and no significant correlation was found between the SBA concentration and the cholesterol concentration or the results of other laboratory tests. These findings suggest that the bile acid metabolism in this group was slightly different from that in the other filariasis groups. The SBA concentration was not uniform after removal of the heartworm. The levels of SBA were 29.4nM±23.4 and 32.5nM±29.3 before and after removal of the heartworm, respectively. Besides, there was no significant correlation between the SBA and plasma hemoglobin concentrations. The latter strikingly decreased after removal of the heartworm. SBA did not seem to directly correlate with intravascular hemolysis in the hemoglobinuria group.