title: [Reference values of antistreptolysin O and asymptomatic carriers of β-hemolytic streptococci in adolescents and adults at Municipality Francisco Linares Alcántara, Venezuela].
abstract: BACKGROUND
  β-hemolytic streptococci (Streptococcus pyogenes) groups A, C or G, secretes streptolysin O, toxin which causes in the infected individual an adaptive humoral immune response with production of serum antibodies called anti-streptolysin O (ASO).
  
  
  OBJECTIVE
  To determine the reference value of ASO in a sample of 159 individuals aged 16-72 years from municipality Francisco Linares Alcántara, Aragua state, applying indirect (passive) agglutination test. By using a throat swab sample which was sown in blood agar 5% the frequency of asymptomatic carriers of β-hemolytic streptococci was also determined.
  
  
  CONCLUSIONS
  As reference value for determining ASO by agglutination method a title of up to 200 IU/mL was obtained, this reference value differs from that recommended by the commercial equipment. Asymptomatic carriers frequency was 21.2% (n = 34). The distribution of β-hemolytic streptococci isolated were: group A (17.6%), group B (32.3%), group C (20.5%), group D (2.9%), group F (8.8%), group G (14.7%) and unclusterable (2.9%).
  
  
  CONCLUSIONS
  The new ASO reference value for teens and adults of the mentioned municipality is up to 200 IU/mL. β-hemolytic Streptococcus group B was the most frequently isolated.
authors.forename: Clara
authors.initials: C
authors.lastname: Gutiérrez
authors.forename: María
authors.initials: M
authors.lastname: Chacón
authors.forename: Luis
authors.initials: L
authors.lastname: Pérez-Ybarra
authors.forename: Hilary
authors.initials: H
authors.lastname: Rivero
authors.forename: Sheryl
authors.initials: S
authors.lastname: Straga
authors.forename: Juan
authors.initials: J
authors.lastname: Luis-León
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000372:Agglutination Tests; D000989:Antistreptolysin / Q000097:blood*; D058345:Asymptomatic Infections; D015415:Biomarkers / Q000097:blood; D002353:Carrier State; D003430:Cross-Sectional Studies; D005260:Female; D006461:Hemolysis; D006801:Humans; D008297:Male; D008875:Middle Aged; D012016:Reference Values; D013290:Streptococcal Infections / Q000097:blood*; D013297:Streptococcus pyogenes; D014687:Venezuela; D055815:Young Adult
chemical_list: D015415:Biomarkers; D000989:Antistreptolysin