STREPTOCOCCAL SEROTYPING

Streptococcus species isolated by other laboratories and implicated in disease processes other than strep throat can be serogrouped.  Serogrouping may be useful, epidemiologically, to relate cases in an outbreak situation.

Specimen Requirements
1. Pure isolates grown on appropriate media.
2. Once growth is apparent send cultures to the laboratory.
3. Specimens should be accompanied by a bacteriology form.

Criteria for Rejection
1. Improper specimen
2. Non-viable specimens
3. Mixed isolates

Shipment
1. Cultures should be shipped as infectious substances according to the federal regulations.
2. Tubed media is preferred but culture plates are accepted if properly packaged and shipped.
3. Ship in a manner to ensure survival of isolate.
4. Complete and enclose bacteriology laboratory form.
5. To promote good recovery of organisms, cultures should be shipped early in the week to prevent them from lying dormant over the weekend.

Reporting/Interpretation
Beta hemolytic isolates will be serotyped against groups A, B, C, F, and G and reported only by serogroup.  Some of the more common species and their relationship to the serogroups are listed below:

Group Streptococcal Species

A  - S. pyogenes

B  - S. agalacticae

C  - S. equi, S. zooepidemicus

F  - S. anginosus

G  - S. canis

 

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