Catalase negative cocci
Streptococci                   Enterococci etc.

   Divided by haemolysis:
I. β-haemolytical II. non-β-haemolytical
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I.β-haemolytical: by polysaccharid C are divided into groups A-Z, important
 S. pyogenes (A group) and S. agalactiae (B group).

S. pyogenes (A group)
Detection:
Direct:
Microscopy: G+ cocci in pairs or chains
Cultivation: full haemolysis on BA
         susceptibility to bacitracin
   pyrase +
   latex agglutination
Indirect: ASLO (detection of antistreptolysin O)
Factors of virulence: capsule, streptolysin O, S, streptokinase, hyaluronidase,   pyrogennous toxin
Pathogenicity: acute tonsilopharyngitis, scarlatina, toxic shock syndrom, impetigo, erysipel,
celulitis, wound infection, fascitis, puerperal sepsis, pneumonia
Late sequellae: rheumatoid fever, acute glomerulonefritis. skin laesions
 Therapy: penicillin, macrolides, lincosamids
Jarkamoce1

S. agalactiae (B group)

Detection:
Microscopy: G+cocci in chains
Cultivation: haemolysis on BA
      positive CAMP test
      latex agglutination

Patogenicity: urinary tract infection, new born babies infections
Therapy: ampicillin, penicillin

camp1 Jarkamoce1

Other hemolytical streptococci (non A non B): wound infections, tonsilitis etc.

II: non-β-haemolytical: S. pneumoniae, oral streptococci etc.

S. pneumoniae
Detection:
Microscopy: G+ lancet-like cocci
Cultivation: blood agar with α-haemolysis (green - viridation)
                solubility in bile, susceptibility to optochin
                  latex agglutination (cerebrospinal fluid)
Factors of virulence: capsule, adhesins, invasins...
Pathogenicity: pneumonia, meningitis, otitis, conjunctivitis, sepsis
Therapy: penicillin, amoxicillin, ceftriaxon, chloramphenicol

Oral streptococci (α-haemolytical streptococci)
Pathogenicity: part of a normal faryngeal flora, can cause dental plaque, caries, endocarditis,
sepsis
Detection: Streptotest