You are viewing the site in preview mode

Skip to main content

Advertisement

You are viewing the new article page. Let us know what you think. Return to old version

Poster presentation | Open | Published:

Bacteriological diagnosis of β-hemolytic streptococci of the upper respiratory tract

Background

Beta-hemolytic streptococci are major human pathogens associated with local or systemic invasion and post-streptococcal immune disorders. We performed a comparison between bacitracin and latex agglutination test for the identification of beta-hemolytic streptococci. We assessed resistance patterns to erythromycin/clindamycin.

Methods

Between January 1 2014 – July 15 2014, 5038 throat swabs were sampled from patients hospitalized in INBI Matei Balş according to standard methods. All beta-hemolytic streptococci suspected colonies were tested with bacitracin (0.04%) disks and we used the latex agglutination kit Omega Latex Diagnostic Avipath Strep. Erythromycin resistance testing was performed by disc 2μg Oxoid and clindamycin 2μg Oxoid on the blood M-H medium.

Results

There were 460 isolates of beta-hemolytic streptococci, bacitracin test was positive for 373 (92.75%). From 87 negative bacitracin test left streptococci, with latex agglutination test, 18 (20.68%) were identified as Streptococcus pyogenes (group A) and 69 (79.32%) were group C, G, B, F. Streptococcus pyogenes had 8.95% resistance to erythromycin, group C streptococci had 2.12%, and group G 45.45. From strains with resistance to erythromycin 75.6% were with inducible resistance to clindamycin and 17.07% had a constitutive one.

Conclusion

Latex agglutination is a preferable alternative to bacitracin testing, providing a definite grouping result.

Resistance of Streptococcus pyogenes to erythromycin was 8.95% compared with group G which had a resistance of 45.45%.

Author information

Correspondence to Alina Borcan.

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Keywords

  • Erythromycin
  • Clindamycin
  • Bacitracin
  • Latex Agglutination
  • Preferable Alternative