in this ppt you will be able to know more about the bacteria that cause menoingitis with its morphology , stain and culture

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.