Neisseria Meningiditis

Question 1

Name the available vaccines for N.meningitidis

Answer 1

Group B protein vaccine.
Group C conjugate vaccine.
Quadrivalent vaccine ACWY

Question 2

How is N. Meningiditis contracted

Answer 2

Through Respiratory droplets

Question 3

Name the infection controls of meningiditis.

Answer 3

Droplets infxn control are introduced before the patient completes 24hr appropriate antibiotics therapy.

Chemoprophylaxis for close contacts 7days prior to disease

Ciprofloxacin for diff age groups, pregnant women.

Vaccination;
Group C conjugate vaccine.
Group B protein vaccine.
Quadrivalent vaccine ACWY.

Question 4

What is the treatment for N. Meningiditis

Answer 4

Third generation cephalosporins
(Ceftriaxone )
And Ciprofloxacin.

Question 5

Serotyping of capsular antigen of Meningiditis is done with?

Answer 5

ELISA.
Enzyme linked immunosorbent assay

Question 6

What are other serotyping that can be done on Meningiditis

Answer 6

PCR–Polymerase chain reaction.
MLST- Multiple locus sequence typing.

Question 7

Meningococcal PCR can be performed on the following except;
CSF
Plasma
Serum
EDTA blood.
Joint fluids
Tears

Answer 7

Tears

Question 8

How many serogroups were obtained?
How many are the commonest?

Answer 8

13
9

Question 9

List the commonest serotypes

Answer 9

A, B C W-135, X, Y, Z
29E, Z’

Question 10

Which of the serotypes are rare

Answer 10

X,Y,Z,Z’,29E

Question 11

Which serotype is an epidemic strain(outbreak) seen in the UK

Answer 11

Type B

Question 12

What is the pattern of disease of serotype A

Answer 12

Epidemic meningitis associated with different clones

Question 13

Which serotypes pattern of disease is associated with local outbreaks?

Answer 13

Serotype C

Question 14

Which of the serotype is common amongst pligrims returning from hajj

Answer 14

W-135

Question 15

Does all the serotypes have vaccines?

Answer 15

Yes aside the rare serotypes

Question 16

What’s the name of the vaccine of serotype C and year of introduction

Tip; Munachi likes men

Answer 16

MenC,
1999..

Question 17

Name of the serotype B vaccine and year of license and introduction

Answer 17

Meningitis B vaccine
Licensed 2013
Introduced into routine schedule;2015

Question 18

Why are isolates of N meningiditis be handled in a safety cabinet

Answer 18

Because they are hazard to employees.
They’re grouped under hazard group 2

Question 19

Name the two specimen usually collected for Meningiditis diagnosis

Answer 19

CSF and Blood

Question 20

List the laboratory investigations done on Meningiditis

Answer 20

Chemical pathology;
Microscopy.
Culture
Serotyping for specific antigen.

Question 21

What are the laboratory findings of CSF in chemopathology in late and early infection

Answer 21

In Late infection:
C.S.F with high pressure.
Appearance: Turbid.
PMN’s and protein level are elevated.
Glucose level is low.

In early infection C.S.F level may be normal

Question 22

List the microscopic findings;

Answer 22

C.S.F findings has a higher yield than blood

It’s a gram Negative intracellular diplococci.

Methylene blue picks up scanty meningococcal

Question 23

List the culture features.

Answer 23

It’s fastidious
Transparent.
Non pigmented.
Non-hemolytic.
Mucoid formation in capsular strains.
Circular colonies.
Oxidase positive

Question 24

List the clinical manifestations of Neisseria meningiditis.

Answer 24

Acute cases;
meningitis.
Purulent conjunctivitis.
Septicemia.
Pericarditis.
Pneumonia

Chronic cases; Septicemia.
In a lesser percentage associated with joint and skin.

Question 25

Briefly discuss the pathogenesis of Meningiditis.

Answer 25

They possess virulence factors that enables it cause disease and aid it’s survival in the host.
A bridge in the nasopharyngeal mucousa activates it pathogenicity.

1)Type IV pili for adherence and colonization.

2) polysaccharide capsule aids in evading phagocytosis by host immunity.

3)lipooligosaccharide does the same thing.

4) IgA protease cleaves the immunoglobulin A seen in mucosa cells.

Various secretion system helps deliver IgA protease and toxin.

Question 26

The only reservoir of Meningiditis is?

Answer 26

Humans
20% carry it as a commensal in their throat

Question 27

What’s the percentage of noncapsulated strains

Answer 27

50%

Question 28

List the risk factors of Meningiditis

Answer 28

Lack of bactericidal activity.
Splenectomy
Bimodal distribution of age group; 3months-3yrs and 18yrs-23yrs
Genetic polymorphisms e.g MBL, TNFA,
FC/RIIa and PAL-1

Question 29

Epidemic cerebrospinal fever was described by who? What year?

Answer 29

Vieusseux
1805

Question 30

Who isolated N. Meningiditis from CSF and year.

Answer 30

Weichselbaum.
1887

Question 31

In what century was meningococcal carriage described?

Answer 31

19th century

Question 32

When was the different serotypes of Meningiditis discovered

Answer 32

1909

Question 33

List the comparison features of n meningiditis

Answer 33

Capsulated.
Half moon shaped(lens shaped)
Maltose and glucose fermenter.
Has no plasmids.
Colony is circular.
Exist in both intracellular and extracellular habitat.

Habitat is nasopharynx(as a bioflora)

Question 34

List the comparison features of N gonorrhoea

Answer 34

Noncapsulated.

Kidney shaped/concave adjacent side.
Intracellular habitat.

Possess plasmids that confer drug resistance.

Glucose fermenter.

Habitat: Genitourinary tract(cervix, vagina) rarely pharynx.

Colony is of varying shapes with irregular margins.

Question 35

Which of the neisseria causes opthalmic neonatorum

Answer 35

N. gonorrhoea

Question 36

List the microbiology of Neisseria meningiditis

Answer 36

Aerobic, gram negative diplococci.
Oxidase positive, grows at 37°c in chocolate and blood agar.
Glucose and maltose positive

Question 37

Iist the microbiology of Neisseria gonorrhoea

Answer 37

Gram- aerobic diplococci.
Oxidase positive,
Grow in 37°c on blood agar and chocolate agar.
glucose +

Question 38

Microbiology features of non pathogenic neisseria species.

Answer 38

They’re aerobic, gram negative diplococci,
Oxidase positive, grow in nutrient agar at 22°c

Question 39

State the microbiology of moraxella catarrhalis

Answer 39

Gram Negative cocci.
Oxidase positive.
Grow on chocolate and blood agar at 37°c.

Question 40

Example of anaerobic gram Negative cocci is?

Answer 40

Veilonella spp

Question 41

Which gram negative cocci is an oral commensal

Answer 41

Non pathogenic neisseria species

Question 42

Which gram negative cocci is a respiratory pathogen

Answer 42

Moraxella

Question 43

Gram negative bacteria has pathogenic and non pathogenic spp..
True or false?

Answer 43

True

Question 44

Explain how splenectomy is a risk factor of Meningiditis.

Answer 44

1) There’s impaired bacteria clearance; as spleen filters blood and removes bacteria from it.

2) There’s decreased antibodies response: they produce antibodies that essentially fight capsulated bacterias…e.g IgM and IgG

Question 45

How is complement protein deficiency a risk factor for Meningiditis pathogenesis.

Answer 45

Complement proteins are group of proteins that work together to oopsonize and destroy bacteria, enhance phagocytosis.
If deficient, these are fxn are impaired.

Question 46

Why is age 3months to 3years a risk factor for Meningiditis

Answer 46

This is because of;
Immature immune system.

Lack of specific immunity against serotypes.

Higher carriage rates in nasopharynx.

Close contact in child care settings.

Question 47

Why is age 18-23yrs a risk factor for Meningiditis.

Answer 47

This is due to;

Increased social interactions

Question 48

How does lack of bactericidal activity serve as a risk factor to Meningiditis.

Answer 48

Impaired phagocytosis by neutrophils and monocytes.

Impaired complement system.