ASO Fast Test Kit (Immunofluorescence Assay) is intended for in vitro quantitative determination of anti streptolysin "O" antibody (ASO) in serum, plasma or whole blood samples. ASO is a very valuable marker for the diagnosis of group A streptococcal infection, its titer can reflect the severity of infection. Some diseases will lead to a significant increase in ASO titer, such as wind damp heat, acute glomerulonephritis, nodular erythema, scarlet fever, acute tonsillitis.