Gel card in the diagnosis of autoimmune haemolytic anemia

The diagnosis of autoimmune haemolytic anaemia (AIHA) requires the establishment of haemolysis and demonstration of autoantibodies against red cells. Most laboratories use the conventional Coomb's test for the demonstration of the autoantibodies. However, in approximately 2-6% of the patients who present with the clinical and haematological features of AIHA, the direct agglutination test is negative on repeated testing. Attempts are therefore being made to identify a test which could be more sensitive than the conventional test, yet retaining the simplicity and cost effectiveness of the test. In the present study, the efficacy of the newly developed gel card test has been compared with the conventional Coomb's test for detection of autoantibodies in 50 cases clinically suspected to have haemolytic anemia. The gel card picked up the antibodies in all the cases detected to be positive by the conventional test. In addition, the gel card also picked up 5 tests which were negative by the conventional method. The sensitivity and specificity of the gel card Direct Coomb's test (DCT) as compared to the conventional tube test for DCT was found to be 100% and 95.1% respectively. The Indirect Coomb's test (ICT) was 100% sensitive and 92.5% specific. In view of the high sensitivity and specificity and the simplicity of the procedure, this test may be effectively used for diagnosis of AIHA.