Treponema pallidum hemagglutination assay, aka TPHA is a test used to identify and detect the dissolved amount of antibodies in patient’s serum against the causes of syphilis which is a sexually transmitted disease which causes papules and nodules across the body of the individual. Alternatively, it might also be caused due to hereditary transfer. It detects Palladium antibodies through the application of a hemagglutination method (HAI). Fowl erythrocytes are sensitized with T. palladium fragments in order to achieve results. In the case of presence of anti-Palladium antibodies, sensitized erythrocytes (Test Cells) clump together and induce a characteristic structure on the micro titer plate.