Antistreptolysin O Determination by Sheep Cell Agglutination

A sheep cell agglutination determination of antistreptolysin O titer was made on each of 98 consecutively submitted serum specimens and compared with the titer obtained by the conventional ASO hemolytic technic. The results were compared by a linear regression analysis; the linear correlation coefficient was 0.82. In addition, 49 of the 98 serum specimens, randomly selected, were examined with the latex agglutination ASO method. The chance of overlooking an elevated (> 166 Todd units) titer with the sheep cell agglutination method is 8.9%, or by following the manufacturers' dilution directions (1/100), only approximately 5%.