M132-1

Throat: No β-hemolytic Group A, C, or G Streptococcus  – Shipped August 2013

HISTORY

The challenge was sent to category A, B, and C laboratories. The sample was a simulated throat swab obtained from a 12 year old female patient with recurrent pharyngitis. The history for this sample stated that the physician required culture.

Laboratories were expected to report the culture negative for specific pathogens.

MAIN EDUCATIONAL POINTS from M132-1

  1. It is important that laboratories recognize small colony forming β-hemolytic streptococci as part of normal oropharyngeal flora even when they possess the Lancefield group A, C, or G antigens.
  2. Large colony pyogenic streptococci can be easily differentiated from the small colony forming Streptococcus anginosus group, by phenotypic testing in the laboratory.

Full critique (PDF)

Posted in Clinical Bacteriology Results, critiques