Neisseria meninigitidis brain infection,meningococcal disease meningococcemia-a life-threatening sepsis. high mortality and morbidity,meningococcal disease needs immediate medical attention initial adherence to the nasopharyngeal (nose and throat) mucosa to invasion of the deeper mucosal layers

1. NEISSERIA MENINGITIDIS
By
S.BHARGAVI
II.M.SC MICROBIOLOGY
Medical Microbiology
UNDER THE GUIDANCE
Mrs.S.Selvajeyanthi
Asst.Professor,
Dept.of Microbiology,
Tiruppur Kumaran College For
Women,Tirupur

2. SYNOPSISSIS :
Introduction
Definition
History
Classifications
Morphology
Virulence Factors
Epidemiology
Etiology
Pathogenesis
Clinical Features
Complications
Laboratory Diagnosis
Treatment

3. INTRODUCTION :
 Neisseria meningitidis is aerobic and bacterial
inflammation of the leptomeninges, usually carried
by bacterial infection .
 Bacterial meningitidis may present acutely
(symptoms evolving rapidly over 1-24 hours),
 symptoms evolving over 1-7 days),or chronically
(symptom evolving more than 1week).
 The word Meningitis is derived from Greek word
‘meninx’ means membrane and ‘itis’ means
inflammation.

4. DEFINITION:
Neisseria meningitidis , offered reffered to as
meningococcus, is Gram - negative bacterium
that can cause meningitidis and other forms of
Meninigococcal disease such as
meningococcemia , a life –threatening sepsis.
Inflammation of the membranes of the brain or
spinal cord.
N. meningitides causes meningococcal meningitis
(formerly known as cerebrospinal fever).

5. Classification :
Kingdom : Bacteria
Phylum : Proteobacteriacea
Class : β-proteobacteria
Order : Neisseriales
Family : Neisseriaceae
Genus : Neisseria
Species : gonorrhoeae , meninigitidis.

6. HISTORY:
 Neisseria meningitidis was first discovered in 1887
by Weichselbaum from analysing the cerebrospinal
fluid(CSF) of a patient infected with meningitidis.
 It is a human-specific baccterium that causes
multitude of illness, collectively termed as
Meningococcal disease.

7. Morphology:
Capsulated Gram-Negative
diplocooci
0.5-1µm.
Kidney shaped , flat sides
adjacent.
Intracellular .
Non-motile .
Non-spore forming .
1

8. Virulence Factors:
ANTIGENS:
•Capsular
polysaccharides
13
serogroups(A,B,C,D,
W135,X,Y,Z,H,K &
L).
•Used in a vaccine
•Serogroups
A,B,C,Y,W135
account for about 90%
of all infections .
 OMP:
• 5 Classes
Serogroups
further
subdivided into
20 serotypes.
 TOXIN:
ENDOTOXIN
• Lipid A part of
lipopolyssacharide
.
• Causes fever and
shock .
 ENZYME:
• IgA
protease.

9. EPIDEMIOLOGY:
Resevior and Habitat:
Incubation Period:
Transmission:
 Upper respiratory tract of humans
 Direct contact and air borne droplets.
 Close contact with infectious
person(eg.,family members,day care
centers,military barracks,prisons and
other institutional setings) .
1-7 days
Carriage:
 5-30% of normal persons may harbor
meningococci in Nasopharnyx.
 Causes between at the age of 2-18
years.
 Highest incidence in children 1-5 years
of age.
 Group A-90%outbreak,Group C-
Africa,Asia and South America , Group
W135-occasionally.

10. ETIOLOGY:
INFECTIOUS
ORGANISM COMMON TYPES DIAGNOSIS:
Bacteria
Haemophilus
influenza,Neisseria
meningitidis,Streptococcus
pneumoniae.
Leukocyte count an
differential Gram stain .
Acridine orange stain
Glucose
Protein culture.
Viruses
Enterovirus
Other(mumps,herps)
Leukocyte count and
differential.
Glucose,Protein,Culture.
Fungi
Cryptococcus neoformans
Candida sp.,
Coccidioides immitis
Gram stain,indian ink
preparation,latex
agglutination culture.

11. Drug-induced
meningitidis:
 Nonsteroidal anti-
inflammatory
drugs(NSAIDs).
 Trimethoprim .
 Isoniazid .
 Others .
Non-infectious:
Carcinomatous
Meningitidis:
 Systemic lupus
erythematous .
 Behcet’s disease .
 Sarcoidosis .
 others

12. Etiology according to patient Age
Age Common bacteria
Birth – 1 Month
S. agalactiae , E . Coli , K.pneumoniae
, L. monocytogenes , enterococcus
species
1 - 3 Months
S. agalactiae , E . Coli ,
L.monocytogenes , H . Influenzae , S.
pneumoniae , N. menimgitidis
3 Months to Over 15 years
S. Pneumoniae , N. meningitidis ,
H.influenzae

13. Pathogenesis
 Bacteria reach the interacranial
strutures in one of the 3 ways
Hematogenous spread
Extension from the juxtacranial
structures.
Latroenic source.

14. Clinical significance
IN ADULTS IN BABIES
Vomiting Fever
Fever Refusing Feeds
Stiff neck Whimpering
Light Aversion Dislike of being handled
Drowsiness Neck retraction
Joint pain Blank and staring
expression
Head Ache Pale, botchy complexion

15.  Specimens:
• Blood and CSF for smear
and culture.
• Nasophyrangeal swab for
carrier state.
 Culture Media:
• Blood Agar
• Chocolate Agar
• Selective
Medium(Modified
• Thayer-Martin medium).
Laboratory Diagnosis

16. Growth Characteristics
 Oxygen Requirement:
a.Aerobic or facultative anaerobic.
Temperature - 37̊c .
Growth promoted by 5-10% of co2.
Colony Morphology
a.1-2mm
diameter,convex,grey,translucent,non-
pigmented and non-hygenic.
b.After 48 hours,colonies are
larger with an opaque raised centre and
transparent margins.

17. Biochemical Reactions:
Oxidase positive
Ferments glucose and
maltose but not sucrose or
lactose

18. SEROLOGY
Latex agglutination test:
•Antibodies to
meningococcal
polysaccharides can be
detected.
•Results are available
within 20-30minutes.

19. Ampicillin /
pencillin
Ceftriaxone
Chloramphenical
Rifampicin
Ciproflaxin
Meropenem.
Antibiotic Sensitivity Test

20. COMPLICATIONS:

21. Treatment:
 Empiric antibiotics
• Cefotaxine
• Vanomycin
• Ampicillin
• Acylovir
 Definitive theraphy
• As per c/s report.
• Penicillin – G is the drug of choice. In penicillin allergic cases,
chloramphenicol is recommended.
• Monovalent and polyvalent vaccines (capsular polysaccharide)
induce good immunity in older children and adults.
• Conjugate vaccines are used for children below the age of 2 years.

22. REFERENCES:
 www.textbook.in microbiology-Medical
Bacteriology pg.no:124-126
 https://www.slideshare.net>kamran66
 https://www.slideshare.net>mobile