Validation of an adenosine deaminase assay and its use in the evaluation of body fluids in dogs.
Adenosine deaminase activity (ADA) (EC 3.5.4.4) was determined according to the method of Slaats and associates in the autoanalyzer Hitachi 705.(1) The analytical quality was controlled. Accuracy was tested by supplementing a sample with an ADA solution. The measured difference of ADA was close to the calculated one. The within-run and between-run precision of the method was sufficient. The detection limit was 1 U/l. ADA measurements were set in relation to a canine plasma pool and expressed as a percent to achieve reproducibility due to the lack of a commercial ADA standard. Body cavity effusions of 156 dogs were examined. The ADA of neoplastic effusions and the ADA of cardiac congestive effusions differed highly significantly (p < 0.001) in pleural and in peritoneal effusions. A discrimination value of 60% for pleural and a discrimination value of 100% ADA for peritoneal effusions separated neoplastic from cardiac congestive effusions. ADA determination in the serum of dogs did not contribute to the etiological differentiation of effusions. The elevation of ADA seemed to originate from the effusion, because the ratio of ADA (effusion/serum) was relatively high in cases of canine neoplasia. In this analysis the ADA in body cavity effusions of dogs was determined for the first time.
Hirschberger
Johannes
J
Department of Internal Medicine, Faculty of Veterinary Medicine, University of Munich, Veterinärstr. 13, D-80539 Munich, Germany.
Koch
Susanne
S