Micro T3 Neisseria
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Clinical diseases caused by Neisseria Gonorrhoeae?
Gonorrhea and Gonococcemia
Neisseria Meningitidis causes what diseases?
Meningitis and Meningococcemia
When do species of Neisseria besides Gonorrhoeae and Meningitis cause disease?
Only if immunocompromised
Prevalence/Mortality of Neisseria Gonorrhea and Meningitidis
- N. gonorrhoeae—high prevalence; low mortality
- N. meningitidis—low prevalence;high mortality (except in belt in Agrica)
Is Neisseria Gram positive or gram negative
What is it's physical appearance?
Is is oxidase positive?
Is it motile?
- Neisseria is GN
- is it a diploccus. Can also form chains.
- It is Oxidase POSITIVE and Aerobic
- It is non-motile
Why did Gonorrhea increase in the 1940s and in the 1980s?
- 1980s-Improved Contraceptives=more sex
What is the only “state” that has more Gonorrhea than Mississippi?
District of Columbia
What are the symptoms of Neisseria meningitidis?
Earache, headache, neck pain, fever, recent vomiting, confusion, inability to follow commands, photophobia, irritability
What are the signs of N. meningitidis?
- Cloudy fluid in lumbar puncture with over 6,000 white cells
- GN Diplococci
- Stiff neck on physical exam
How long does it take for symptoms of N. meningitidis to show up?
Is N. meningitidis oxidase/catalase positive/negative?
Oxidase and catalase positive
What kind of agar does N. meningitidis grow on?
Chocolate blood agar (slightly fastidious) or Thayer Martin agar
What are the virulence factors of Neisseria meningitidis?
- Polysaccharide capsule
- Serogroups A, B, C, Y, and W-135 are in 90% of infections
- LOS(shorter side chain than LPS)
- Por and Opa proteins
- Reduction-modifiable protein
- Membrane blebs
- IgA1 protease
- Iron acquiring proteins
How do the pili of N. meningitidis help with virulence?
- Attach to epithelial cells
- Resistance to killing by neutrophils
- Phase variation/antigenic variation in pilin proteins
- Induce antigens that lead to ruffling of membrane and allows access of organism into the cell
- (it’s hard for the host to recognize organism when it is inside the cell)
How does the LOS of N. meningitidis help w/virulence?
The lipid A (endotoxin moiety) stimulates inflammatory response and release of TNF-a
How do the PorB proteins of N. meningitidis work?
- They are outer membrane proteins that form pores
- They protect the bacteria from the host’s inflammatory response
- They facilitate bacterial invasion into epithelial cells
How do the Opa proteins of N. meningitidis work?
- They are Outer Membrane Proteins
- They bind to epithelial cells
What is the role of Reduction-modifiable protein (RMP) in N. meningitidis virulence?
- Outer membrane protein
- IgG and IgA1 antibodies directed against these inferfere with the bactericidal action of the antibodies directed against LOS (co-interference, which is good for survival of bacteria)
What iron acquisition proteins are included in the N. meningitidis?
Transferrin, lactoferrin, and hemoglobin binding proteins
How do membrane blebs help with N. meningitidis virulence?
- They may enhance endotoxin-mediated toxicity
- They protect bacterial cells from antibodies (like a decoy)
How does the IgA1 protease help with virulence?
It degrades mucosal IgA
Characterisitcs of Meningitis (disease)?
- Disease begins abruptly, often with fever/headache/stiff neck
- May see non specific signs in young children
- Mortality is 10% w/therapy, almost 100% without therapy
- Sequelae include hearing deficits, learning deficits, and arthritis
What are the charactersistics of Meningococcemia (disease)?
- Septicemia (w or w/o meningitis)
- Multiorgan involvement
- Petechial skin lesions that make larger hemorrhagic leisions
- DIC and shock
What is serum resistance for N. meningitidis?
- The organism can survive in serum by inactivating complement
- --blocks the formation of the C5b-9 complex Membrane Attack Complex) by binding factor H and C5b
What are the components of the Meningitis Vaccine? When is it given?
- 4 serogroups (A, C, Y, and W-135)—Not B serogroup due to too many side effects
- Conjugate Vaccine (MCV4)
- Recommended for preadolescence with a booster before college or 1st shot before college
Treatment of N. meningitidis/Prevention
- MCV4 vaccine to prevent at 11-12 years old and boost at college age (close quarters=outbreaks)
Other diseases caused by N. meningitidis
Epidemiology of N. meningitidiis
- Humans are only natural host
- Aerolized spread
- Highest incidence in 16-21 year olds****
- Occurs most commonly in dry, cold months
Where do N. sicca and N. mucosa live? What do you treat them with? What diseases do they cause?
- Oropharynx (commensals)
- Susceptible to penicillin
- Meningitis, osteomyleitis, otitis media, sinustitis
Morphology/Gram stain/Classification of Eikenella corrodens
- GN non spore forming rod
- Facultative anaerobe
Where does eikenella corrodens normally live? What injury is it associated with? What do you treat with
- Human oropharynx
- Human bite wounds or fistfight injuries
- Susceptible to penicillin, ampicillin, cephalosporins, tetracycline, and fluroquinolones
What does eikenella corrodens look like when it goes?
Indents/corrodes the agar when it grows
What are the HACEK diseases? What do they cause?
- They cause subacute endocarditis
What is the gram stain of Kingella kingae? Where does it live? What do you treat with?
- GN coccobacillus
- Lives in human oropharynx
- Treat with penicillin, tetracycline, erythromycin, fluoroquinolones, and aminoglycosides
What does Kingella kingae cause?
What is the gram stain Moraxella catarrhalis? Is it aerobic? Is it oxidase positive?Where does it live?
- GN diplococcic
- Aerobic and oxidase positive
- Lives in human respiratory tract (commensal). Most often seen in children or adults with COPD.
What diseases are associated with Moraxella catarrhalis?
- 3rd leading cause of otitis media in young children
- Bronchitis and bronchopneumonia in elderly patients with COPD (Major cause of COPD exacerbations)
What is a virulence factor that Moraxella catarrhalis has that makes it harder to treat?
Has a beta lactamase, so it indirectly protects other pathogens from penicillin and is harder to treat
What are other virulence factors of M. catarrhalis?
- Inactivates complement
- Biofilm important in otitis media
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