Neisseriacaea Flashcards
Are neisseriacaea oxidase negative or positive?
Oxidase positive
Neisseriacaea mode for motility?
Imotile. Non flagellated
Neisseriacaea response to oxygen?
Strict aerobes
What is the main pathogen in Neisseriacaea?
Neisseria
What is the morphology is neisseria?
Dipplococci
What is pyogenic?
Pus forming
Where to neisseria reside in the body?
In The WBC.
Resistant to phagocytosis
What is the major virulence factor of neisseria gonorrhaea?
Pilli. Pilin adhesion to the epithelial cells allows uptake by endocytosis.
Non capsulated
In gonorrhoea, what acts on the macrophages to release TNF?
Endotoxins (lipopolysaccharides) that are released by neisseria gonorrhaea
What causes the cell damage in the urethra in gonorrhoea?
Inflammation caused by the inflammatory cytokine TNF which is released by macrophages.
Why is it a common problem that N.G can go on to cause pelvic inflammatory disease in women?
Because it is often asymptomatic in women. So treatment is not seeked.
What are some secondary diseases that can be caused if N.G becomes systemic?
PID, meningitis, endocarditis, arthritis, dermatitis
Which three bacteria can cause meningitis?
Neisseria meningitidis
Meningococcal septicaemia
Meningococcal meningitis
What causes the initial bacteremia in meningitis from N.meningitidis?
Invasion of the bloodstream from the nasopharynx where it is commensal in 10-20% of pop.
What is the progression of meningitis caused by N.Meningitidis?
Commensal Bacteremia Septicaemia Cross BBB CNS infection > meningitis
What is the key virulence factor of N.meningitidis?
LPS.
Shed as membrane blebs- stimulating cytokine release from host cells causing inflammation.
What is ‘shock’?
Catastrophic drop in blood pressure due to internal bleeding.
Hard to reverse
Which form of meningitis causes gangrene, organ failure and shock?
Meningococcal septicaemia
What are the three meninges of the brain
Arachnoid, dura mater, Pia mater
Why is meningitis difficult to diagnose in infants and adolescents?
Common symptoms
Headache, fever, photophobia, malaise
What is the treTment for meningitis?
Intravenous benzyl penicillin. [best at passing BBB]
Treatment must be early to be effective.
How is meningitis serotyped?
Classified by composition of capsular LPS.
A B C & Y
What is the most common worldwide serotype of meningitis?
A
Which meningitis serotyped are most common I’m Europe and USA?
B & C
