Collection of Specimens
  •  The type of specimen required for the diagnosis of S. aureus 
     depends on the site of the infection. 
  •  Patients contribute a urine sample for the diagnosis of urinary tract 
     infections. 
  •  For blood infections, lab technicians withdraw blood from the patient 
     using a syringe and transfer it to a blood culture bottle.
   
  •  Swabs, which consist of a sterile absorbent material such a cotton, 
     are used to collect specimens from throat, nostrils, skin, wounds and 
     other accessible lesions. 
                                          TASKS 
  group 1                  group  2                      group  3                       group  4
  S. aureus – GRAM         S. epidermidis – GRAM         S. aureus +                    S. aureus - GRAM
                                                         S. epidermidis -GRAM
  G+ and G- cell wall  Describe the GRAM                                                ATB susceptibility 
  structure                staining procedure            ATB susceptibility test:       test: E-test - 
                                                         Disc diffusion Test -          principle
                                                         principle
  S. aureus –              S. epidermidis -              S. aureus –                    S. epidermidis - 
  cultivation on           cultivation on blood          catalase test                  catalase test 
  blood agar-              agar – describe               Describe principle of 
  describe colonies        colonies                      catalase test 
  S. aureus –              S. epidermidis -              S. aureus – bound              S. epidermidis – 
  cultivation on salt      cultivation on salt           plasmacoagulase test           Describe principle 
  mannitol medium          mannitol medium –             (clumping factor)              of free 
                           describe the principle                                       plasmacoagulase 
                                                                                        test
        Microscopy
  • Cuture of Staphylococcus aureus - fixed 
   and stained by Gram:                                  
                         - G+ cocci in clusters
       sputum - staphylococci + 
              pneumococci
                       staphylococci
      leucocyt
                           pneumococci
  Pus – intracellular localization