Tehran University of Medical Sciences Iranian Journal of Public Health 2251-6085 5 3 1976 09 15 155 164 A Bollourian K. Yazdani M. Horriat 2015 10 03 Nine hundred and twelve, consecutive patients attended various clinics of Isfahan University for various complains have been evaluated for A.S.O. Titers among whom 172 has positive nasopharyngeal cultures for type A, B hemolytic streptococcus. All of the patients with positive cultures have A.S.O. Titers of above 333 Todd’s unit, while with exception of 22 cases all of the others had values of less than 333. All of the patients, with positive cultures were in their second or third decades of life. According GO these findings we suggest that A.S.O. values of more than 333 Todd units should be accepted as an important finding favoring streptococca1 infection. https://ijph.tums.ac.ir/index.php/ijph/article/view/2427 https://ijph.tums.ac.ir/index.php/ijph/article/download/2427/2407