Practical 7 ST                                                
      anaerobic cultivation  
  • Bacteria in relation to oxygen 
  • Anaerobic infections - sampling and 
   transport 
  • Cultivation                                                                       
   - establishing of anaerobic environment                                                                           
   - anaerobic culture media,                                                                 
   - procedure: inoculation, isolation 
    
         Anaerobes 
  • are the predominant components of the 
   skin’s and mucous membranes normal flora  
   - cause infections of endogenous origin 
  • mixed infections caused by numerous 
   aerobic and anaerobic bacteria are often 
   observed in clinical situations. 
      Anaerobic infections  
 • Usually endogenous bacteria - disturbance of the 
  balance of normal flora (ATB and colon microflora) 
  or unusual anatomic sites (perforation of colon - 
  anaerobic peritonitis) 
 • Exogenous bacteria - wound contamination 
 • Exudate, pus, abscess  
 • Sampling and transport in anaerobic conditions - 
  aspirate in the syringe with the needle capped or 
  protected with rubber. Surgical sampling can be 
  required. Never use the dry swab! 
      Anaerobic bacteria 
  can be divided into:  
  • strict anaerobes that can not grow in the 
   presence of more than 0.5% oxygen  
  • moderate anaerobic bacteria that are able of 
   growing between 2 to 8% oxygen.  
  • Anaerobic bacteria usually do not possess 
   catalase 
  • can generate superoxide dismutase which 
   protects them from oxygen.