Features | S. pneumoniae | Viridans streptococci |
---|---|---|
Arrangement | Gram +ve cocci in pairs | Gram +ve cocci in long chains |
Morphology | Lanceolate shaped | Round/ Oval |
Capsule | Present | Absent |
On blood agar | Draughtsman or Carrom coin colony | Minute colony |
Bile solubility | Soluble | Insoluble |
Inulin fermentation | Fermenter | Non-fermenter |
Optochin sensitivity | Sensitive | Resistant |