0:00:06.308,0:00:11.318 A saline agglutination test is a very easy in-house diagnostic procedure 0:00:11.669,0:00:16.521 and should be performed in any patient with suspected hemolytic anemia. 0:00:16.723,0:00:22.761 It is redundant if gross agglutination is noted in the CBC sample or the hematocrit tube. 0:00:23.371,0:00:27.808 Simply place a drop of EDTA blood on to a microscope slide. 0:00:29.755,0:00:36.045 Add a drop of 0.9% NaCl and mix it with the blood. 0:00:36.145,0:00:39.462 Look under the microscope at the red blood cells. 0:00:39.548,0:00:44.600 Check for agglutination, which is characterized by persistent clumping of cells. 0:00:44.832,0:00:48.808 If you disturb the slide, the cells will stay attached to each other. 0:00:49.217,0:00:57.609 It can be difficult to differentiate rouleaux formation from true agglutination because these processes can look similar at first glance. 0:00:57.921,0:01:04.094 However, cells in rouleaux tend to stack rather than clump, and they dissipate when disturbed. 0:01:05.138,0:01:12.086 Remember that a positive saline agglutination test indicates that there are antibodies on the surface of the erythrocytes. 0:01:12.559,0:01:18.543 This supports a diagnosis of immune-mediated hemolytic anemia (IMHA). 0:01:18.884,0:01:28.221 However, positive agglutination tests can occur in patients with other causes of hemolysis, such as zinc ingestion or erythrocyte parasitism. 0:01:28.751,0:01:38.424 Conversely, some dogs with IMHA do not have a positive saline agglutination test, so a negative result does not exclude this diagnosis.