Gram - Respiratory Pathogens Flashcards
What type of bacteria is Neisseria?
gram - diplococci
What is closely related to Neisseria and a common cause of Otis media in children?
Moraxella catarrhalis
What is the only reservoir of Neisseria?
humans which inhabit mucosal surfaces
What are the 2 main species of neisseria?
N. meningitisdis and N. gonorrhoeae
T/F: 5-30% of the population carry N. meningitidis.
True!
This could be the cause of occasional outbreaks
How is n. meningitidis transmitted?
large droplets in close range
susceptible in military groups
T/F: meningitis is not a cause of concern regarding mortalities
False!
10-15% die even with antibiotics with the highest age group 15-24
What happens after getting N. meningitidis?
carrier or severe disease: systemic inflammation (sepsis) depending on if capsule present and/or meningitis
T/F: N. gonorrhea goes through the blood stream
False!
It always stays on the surface on urethral cells
What is the vaccine for gonorrhea?
none
What does the body recognize in gram -?
the LPS and body will produce cytokines for inflammation
What is the LPS in respiratory bacteria like hemophalus and meniningits?
slightly different LPS called LOS endotoxin
has no O-antigen
T/F: N. meningitidis has a capsule polysaccharide
True!
Major virulence factor used for vaccine
What is a very distinctive feature of N. meningitidis?
they have a diplococci shape with pili/fimbriae
Does N. meningitidis have exo-toxins?
No but they do have eco-enzymes: IgA protease (similar in strep pnuemoniae)
Why didn’t the old vaccine for N. meningitidis not work on children?
because children can’t react to a pure carbohydrate vaccine so requires polysaccharide conjugated to protein
What do they use for B capsule strains of meningitis?
2 outer membrane proteins
What do all gram - bacteria release?
blebs or outer membrane vesicles which means it is another mean of DNA exchange and new generations must be made to keep up with the resistance
T/F: Haemophilus is a major part of the normal flora of upper respiratory tract
True
The normal ones do not have a capsule but disease causing ones do
How does Haemophilus spread?
person-to-person by inhaling airborne droplets and shared secretions
What can be caused by Haemophilus?
sinusitis, pink eye, and pneumonia
How are invasive infection of Haemophilus influenza spread?
type b capsule strains causing septicemia and meningitis
What has LOS?
H. influenza and N. meningitis
Which is gram +: neisseria meningitidis, haemophilus influenza, or streptococcus pneumoniae?
streptococcus pneumoniae
All are upper respiratory infections and all can cause meningitis by going through bloodstream with the capsule
Is bordutella pertussis normal flora?
No, not normal flora and no carrier
Who is most susceptible for B. pertussis?
newborns due to lack of maternal Ab
Where B. pertussis attach?
attach to cilia (everything else is usually epithelial cells) and then kill epithelial cells so throat is without protection
What are the 3 secreted extracellular toxins of B. pertussis?
pertussis toxin (cause macrophages to slow down)
adenylate cyclase toxin (cause macrophages to slow down)
tracheal cytotoxin
How do the Pertussis toxins work in B. pertussis?
cause imbalance cAMP making macrophage less active or make epithelial cells move ions
-also major component of acellular vaccine toxoid
How does tracheal cytotoxin work in B. pertussis?
controversal because it is a peptidoglycan monomer
but inhibits ciliated epithelial cells and triggers inflammation
