[Table/Fig-2]:
Criteria for differentiation of phenotypes of MLSB resistance in S. aureus
| Phenotype | Induction test type |
Clindamycin sensitivity | Erythromycin Sensitivity |
Remark |
|---|---|---|---|---|
| Inducible MLSB | D | S (→ R) | R | Blunted D-shaped clear zone around CD, near E. |
| Inducible MLSB | D+ | S (→R) | R | Blunted D-shaped zone around CD near E and small colonies growing into CD zone in an otherwise clear zone. |
| Constitutive MLSB | Hazy D Inducible + Constitutive |
R | R | Sometimes 2 zones of growth appear around CD. An inner zone of light growth and an outer zone of confluent growth. The inner zone is blunted, near to E. |
| Constitutive MLSB | R | R | R | No hazy zone. Growth up to both E and CD. |
| MSB | Negative | S | R | Clear susceptible zone around CD. |
| CL§ | Negative | I/R | S | Clear susceptible zone around E. No zone around CD or reduced zone size (< 21 mm). |
| No resistance | S | S | S | Clear susceptible zone diameter. |
§CL= Constitutive lincosamide resistance