Asymptomatic infection by Streptococcus pyogenes in schoolchildren and diagnostic usefulness of antideoxyribonuclease B

J Korean Med Sci. 2005 Dec;20(6):938-40. doi: 10.3346/jkms.2005.20.6.938.


This study is designed to evaluate the immune status of schoolchildren with respect to Streptococcus pyogenes, and to ascertain the usefulness of antideoxyribonuclease B (ADNase B). Antistreptolysin O (ASO) and ADNase B concentrations were measured quantitatively in 266 serum samples from healthy elementary school children in Seoul. Simultaneously, throat cultures were taken in order to isolate S. pyogenes and other beta-hemolytic streptococci (BHS). The upper limits of the normal (ULN) concentration of ASO and ADNase B were 326 IU/mL, and 362 IU/mL, respectively. The correlation between ADNase B (y) and ASO (x) was y = 0.4x+173 (r = 0.46). Mean ADNase B level (392 IU/mL) was significantly higher in children with S. pyogenes than in those with non-group A BHS (236 IU/mL) or no BHS (234 IU/ mL). Some schoolchildren were proven, via ASO and ADNase B tests, to be harboring asymptomatic S. pyogenes infections. The high ULN of ASO and ADNase B in schoolchildren should be carefully considered, in order to interpret the data collected from the patients. We could add the ADNase B test to our set of diagnostic tools, which would allow us to more accurately detect and diagnose streptococcal infections, as ADNase B was more specifically related to the results of throat cultures, and there was little correlation between ASO and ADNase B.

MeSH terms

  • Antibodies, Bacterial / blood*
  • Bacterial Proteins / immunology
  • Child
  • Deoxyribonucleases / immunology*
  • Female
  • Humans
  • Korea
  • Male
  • Serologic Tests
  • Streptococcal Infections / diagnosis*
  • Streptococcal Infections / immunology*
  • Streptococcus pyogenes / enzymology
  • Streptococcus pyogenes / immunology*
  • Streptolysins / immunology


  • Antibodies, Bacterial
  • Bacterial Proteins
  • Streptolysins
  • streptolysin O
  • Deoxyribonucleases
  • deoxyribonuclease B