The document discusses various bacterial pathogens causing meningitis, including Neisseria meningitidis and Streptococcus pneumoniae, along with their identification through specific culture media and tests. It details the use of enriched and selective media like chocolate agar and modified Thayer-Martin medium for culturing fastidious organisms, as well as the biochemical reactions and hemolytic patterns observed in different bacteria. Additionally, it describes the requirement for specific growth factors in Haemophilus influenzae and methods for antibiotic susceptibility testing.

1. Bacterial meningitis

2. Neisseria meningitidis
Streptococcus
pneumoniae
Streptococcus
agalactiae
(streptococcus group B)
Escherichia coli
Hemophilus influenza

3. Neisseria meningitidis
 Gram stain:
Gram negative diplococci
intracellular in pus cells as well as
extracellular

4. Basic stain
Acetone-alcohol

5.  Culture on chocolate agar
 Type: enriched media
 Use: culture of fastidious organisms as Neisseria
and Haemophilus
 Modified Thayer–Martin medium is a selective medium for
pathogenic Neisseria. It contains lysed blood agar and three
antibiotics (VCN :Vancomycin, Colistin and Nystatin).

6. Need 5-10% CO2 for growth Candle jar

7.  Identify:
Anaerobic jar used as candle jar
 Use:
Culture of bacteria that need 5-10% CO2
for growth as Neisseria

8.  Biochemical reactions:
Oxidase test
Name of the test
Interpret result
Give an example

9. Streptococcus pneumoniae
Gram positive diplococci

10. • Culture media :
● Blood agar :
colonies grow on blood agar and surrounded by
αlpha - haemolysis.
Quelling reaction:
When Pneumococcus of certain antigenic type is mixed
with specific anti-polysaccharide serum of the same type
or with polyvalent antiserum on a microscope slide, the
capsule swells markedly.

11. Streptococcus agalactiae
(streptococcus group B)
Gram positive cocci

12.  Grow on blood agar and
produce complete beta
hemolysis

13. Escherichia coli
Gram negative bacilli

14. MacConkey agar
 Type: differential selective medium
 Use: Cultivation of enteric bacteria and differentiation
between two major groups of enteric bacteria:
(1) Lactose fermenting bacteria:
• Give pink colonies.
• e.g. E. coli, Klebsiella.
(2) Lactose non-fermenting bacteria:
• Give pale colonies.
• e.g. Salmonella, Shigella, and Proteus.

15. Haemophilus influenzae
Gram negative coccobacilli

16.  Culture on chocolate agar
 Type: enriched media
 Use: culture of fastidious organisms as
Neisseria and Haemophilus

17. X and V factor Test
 H. influenzae are fastidious organisms. Media for their
growth should contain X and V (NAD) factor:
 X factor is a hemin . V factor is nicotinamide adenine
dinucleotide (NAD).
 Bacteria require media containing X and V factor that
are essential for their growth.

18. Mueller-Hinton agar
 Use:
Antibiotic susceptibility testing

19. Zone of inhibition

20. Bacteriological loop
 Use: inoculation of bacteria
on culture media
 Method of sterilization:
Dry heat (red heat) by heating
in the Bunsen flame till it
turns red hot.