Bacteria

• Diagnostic Features & How to differentiate between

  • Gram +ve & Gram -ve
  • Gram +ve Cocci
  • Gram -ve Cocci
  • Gram +ve Bacilli
  • Acid-Fast Bacilli
  • Gram -ve Bacilli
• Gram stain


  If violet = Gram +ve, if red = Gram -ve
• How to differentiate between Gram +ve & Gram -ve

  • Use Gram stain
• Pathology


  • Gram +ve Cocci
  • Gram -ve Cocci
  • Gram +ve Bacilli
  • Acid Fast Bacilli
  • Gram -ve Bacilli
• Virulence Factors


  • Gram +ve Cocci
  • Gram -ve Cocci
  • Gram +ve Bacilli
  • Acid-Fast Bacilli
  • Gram -ve Bacilli
  • Acid-Fast Bacilli
• Transmission


  • Where/How to get infected with it & the most likely targeted groups
  • Gram +ve Cocci
  • Gram -ve Cocci
  • Gram +ve Bacilli
  • Acid-Fast Bacilli
  • Gram -ve Bacilli
• Shape & Arrangement


  • Gram +ve Cocci
  • Gram -ve Cocci
  • Gram +ve Bacilli
  • Acid-Fast Bacilli
  • Gram -ve Bacilli
  • Acid-Fast Bacilli
• Reservoir

  • Gram +ve Cocci
  • Gram -ve Cocci
  • Gram +ve Bacilli
  • Acid Fast Bacilli
  • Gram -ve Bacilli
• Prevention


  • Gram +ve Cocci
  • Gram -ve Cocci
  • Gram +ve Bacilli
  • Acid-Fast Bacilli
• Antibiotics


  • Gram +ve Cocci
  • Gram -ve Cocci
  • Gram +ve Bacilli
• Catalase


  If +ve = Staphylococci, if -ve = Streptococci
• Coagulase


  If +ve = Staphylococcus aureus, if -ve = Staphylococcus epidermidis

  
• Beta-hemolysis

  Staphylococcus aureus, complete destruction of RBC
• Non-hemolysis


  Staphylococcus epidermidis
• Staphylococcus Aureus lab diagnostics

  • Gram +ve
  • Coagulase +ve
  • Catalase +ve
  • Beta hemolysis on blood agar
  • Imparts a golden color on blood agar
  • Ferments mannitol salt agar
• Staphylococcus saprophyticus


  Resistant to novobiocin
• Staphylococcus Lugdunensis


  • Decarboxylates ornithine
  • Positive PYR test
  • May produce a bound form of coagulase
• Beta hemolysis


  Complete destruction of RBC, Streptococcus pyogenes
• Alpha hemolysis


  Partial destruction of RBC, Streptococcus pneumoniae
• Bacitracin


  Resistant, Streptococcus agalactiae
• PYR


  Negative, Streptococcus agalactiae
• Hippurate


  Hydrolyzes, Streptococcus agalactiae
• cAMP test


  Positive, Streptococcus agalactiae
• Optochin


  Sensitive, Diplococcus pneumoniae
• Bile


  Lysed by, Diplococcus pneumoniae
• Optochin


  Resistant, Viridans Streptococcus
• Bile


  Resistant, Viridans Streptococcus
• PYR


  Positive, Enterococcus
• Esculin


  Hydrolyzes, Enterococcus
• Vancomycin


  Resistant, Enterococcus
• Gram stain


  Gram -ve, red, Neisseria gonorrhoeae
• Oxidase


  Positive, Neisseria gonorrhoeae
• Sugar fermentation


  Glucose only, Neisseria gonorrhoeae
• Gram stain


  Violet = Gram +ve = Streptococcus pneumoniae, Red = Gram -ve = Neisseria meningitidis
• Chocolate agar


  Grows on, Neisseria meningitidis
• Sugar fermentation


  Glucose & maltose, Neisseria meningitidis
• Oxidase


  Positive, Neisseria meningitidis
• Sugar fermentation


  • Glucose only, Neisseria gonorrhoeae
  • Glucose & maltose, Neisseria meningitidis
• Beta lactamase


  • Produces, Neisseria gonorrhoeae
  • Does not produce, Neisseria meningitidis
• Capsule


  • No capsule, Neisseria gonorrhoeae
  • Polysaccharide capsule, Neisseria meningitidis