1. Neisseria meningitidis
Pratthana Srisangthong

2. What should be known about N. meningitidis?
Gram negative diplococci
Capsular polysaccharides
Thirteen serogroup : A, B, C, D, X, Y, Z, E,
W-135, H, I, K and L
Outer membrane
Lipo-oligosaccharide
Serogroup specific antibodies arise during carrier state
Serological cross reactivity

4. What should be known about N. meningitidis?
Colonization or carrier state V.S. disease
Carrier state : chronic, intermittent and transient
Transmission from carrier to carrier : via respiratory route ( droplet )
Disease epidermic is associated with rapid rate of spreading of the carrier state
Invasive disease occurs in seronegative persons with a newly acquired, virulence meningococcus in the presence of appropiate factors.

5. Pathogenesis Nasopharyngeal attach and colonization
Preexisting condition
smoking, prior URI,
crowdy, household contact
Nasopharyngeal attach and colonization
Disease causing strain
Entering into the epithelial cell
Intracellular survive and transportation
Deficiency of antimeningococcal
antibody
invasion
Survival in blood stream

6. Risk factors for invasive meningococcal infection
Factor associated colonization
Patients with anatomical or functional splenectomy
Complement deficiency
Microbiologists routinely exposed to N. meningitidis
Travelers to epidermic region

7. Meningococcemia in Thailand
The majority of cases are caused by serogroup B.
The incidence is rare.

8. Epidermiology Saharan africa has greastest percents.
Most case arise in children
Menigococcal disease occurs more commonly among household contacts
Most secondary cases occur within 2 weeks of the primary case

9. Clinical manifestations
Bacteremia without sepsis
Meningococcemia without meningitis
Meningitis with / without meningococcemia
meningoencephalitis

10. Generalized malaised
Weakness
Headache
Sepsis
Leucocytosis
Rash
Myocarditis
Shock DIC
Massive hemorrhagic
pulmonary edema
Subendocardial hemorrhage
Adrenal hemorrhage

13. Uncommon manifestations
Arthritis
Pericarditis immunologic reaction
Conus medullaris syndrome
CN dysfunction ( VI, VII, VIII )
Pneumonia
Urethritis

14. Poor prognotic factors
Extremes of age
A short period between onset of disease and admission
The absence of meningitis
Wide spread skin leision ( purpura fulminans)
Shock and / or MODS including DIC
The absence of leukocytosis
High concentration of cytokines eg IL-10

15. Laboratory diagnosis Bacterial isolation from sterile sites
Bacterial antigen in CSF : CIE, latex agglutination
PCR in blood and CSF

16. The number of deaths can be reduced by
Early recognition and correct management
Prompt chemoprophylaxis of close contacts
Rapid mass vaccine vaccination

17. Treatment Early therapy Antibiotic therapy ceftriaxone 2 g/d
PGs 18 – 24 mU/d
chloramphenical 4 g/d
Early therapy

18. Non antibiotic therapy
Supportive care
Role of corticosteroid ???
Heparin not indicated
New therapy
-activated protein C in severe sepsis
-recombinant protein composed of the N terminal fragment of human bactericidal/ permeability – increasing protein ???

19. Chemoprophylaxis Rifampicin 1,200 mg/d 2 d Ciprofloxacin 500 mg/d 1 d
Ceftriaxone 259 mg im 1 dose
Start within
2 week
90 – 95 % efficacy
In eradication of nasopharyngeal carrier
and absence of secondary case

20. Who should recieve?
The household contact during epidermic and endermic situation ( direct and indirect contact )
Close population : college dormitories, long term care hospitals, nursery schools, day care center and military barracks
Medical personnels who have exposure : > 8 hr contact while in close proximity ( 3 feet ) , direct exposed the patients’ oral secretion eg ETT , mouth to mouth resusutation

21. Immunoprophylaxis Vaccine derived from capsular polysaccharide
of group A and C
Quarivalent product containing capsular polysaccharidecof group A, C, Y, W-135
No vaccine in group B
The protection lasts 2- 4 yr
Poor immunogenic in infants and short protection in children < 2 yr

22. Immunization is recommended in
High risks eg complement deficiency,persons with splenectomy
Military recruits
Freshmen living in dormitories
Microbiologists routined exposed to
N. meningitidis
Travelers to hyperendemic , epidermic area
Thank you