Streptococcal antibodies among rural school children in Bangladesh

The upper limit of normal values of group A streptococcal antibodies should be known for a population concerned because it is influenced by many local conditions. As yet the reference value of the these antibodies has not been determined by using a quantitative method among Bangladeshi children. We determined the reference value of anti-streptolysin O and anti-deoxyribonuclease B among 361 apparently healthy rural Bangladeshi primary school children (aged 5 to 14 years, mean 9.2 years). Anti-streptolysin O was measured by an auto-analyzer and antideoxyribonuclease B was measured by microtitre method. The geometric mean titres for the entire group was 241 IU/ml and 222 IU/ml for anti-streptolysin O and anti-deoxyribonuclease B respectively. The upper limit of normal values (80th percentile) was 390 and 340 for anti-streptolysin O and anti-deoxyribonuclease B, respectively. These limits should be of value to physicians, epidemiologists and clinical laboratory personnel as well.