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Clinical diseases caused by Neisseria Gonorrhoeae?
Gonorrhea and Gonococcemia
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Neisseria Meningitidis causes what diseases?
Meningitis and Meningococcemia
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When do species of Neisseria besides Gonorrhoeae and Meningitis cause disease?
Only if immunocompromised
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Prevalence/Mortality of Neisseria Gonorrhea and Meningitidis
- N. gonorrhoeae—high prevalence; low mortality
- N. meningitidis—low prevalence;high mortality (except in belt in Agrica)
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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
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Why did Gonorrhea increase in the 1940s and in the 1980s?
- 1940s-WWII
- 1980s-Improved Contraceptives=more sex
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What is the only “state” that has more Gonorrhea than Mississippi?
District of Columbia
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What are the symptoms of Neisseria meningitidis?
Earache, headache, neck pain, fever, recent vomiting, confusion, inability to follow commands, photophobia, irritability
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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
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How long does it take for symptoms of N. meningitidis to show up?
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Is N. meningitidis oxidase/catalase positive/negative?
Oxidase and catalase positive
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What kind of agar does N. meningitidis grow on?
Chocolate blood agar (slightly fastidious) or Thayer Martin agar
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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)
- Endotoxin
- Pili
- Por and Opa proteins
- Reduction-modifiable protein
- Membrane blebs
- IgA1 protease
- Iron acquiring proteins
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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)
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How does the LOS of N. meningitidis help w/virulence?
The lipid A (endotoxin moiety) stimulates inflammatory response and release of TNF-a
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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
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How do the Opa proteins of N. meningitidis work?
- They are Outer Membrane Proteins
- They bind to epithelial cells
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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)
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What iron acquisition proteins are included in the N. meningitidis?
Transferrin, lactoferrin, and hemoglobin binding proteins
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How do membrane blebs help with N. meningitidis virulence?
- They may enhance endotoxin-mediated toxicity
- They protect bacterial cells from antibodies (like a decoy)
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How does the IgA1 protease help with virulence?
It degrades mucosal IgA
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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
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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
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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
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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
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Treatment of N. meningitidis/Prevention
- Penicillin
- Cephalosporins
- MCV4 vaccine to prevent at 11-12 years old and boost at college age (close quarters=outbreaks)
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Other diseases caused by N. meningitidis
- Pharyngitis
- Pneumonia
- Urethritis
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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
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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
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Morphology/Gram stain/Classification of Eikenella corrodens
- GN non spore forming rod
- Facultative anaerobe
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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
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What does eikenella corrodens look like when it goes?
Indents/corrodes the agar when it grows
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What are the HACEK diseases? What do they cause?
- Hemophilus
- Actinobacillus
- Cardiobacterium
- Eikenella
- Kingella
- They cause subacute endocarditis
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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
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What does Kingella kingae cause?
Septic arthritis
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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.
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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)
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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
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What are other virulence factors of M. catarrhalis?
- Adhesions
- Inactivates complement
- Biofilm important in otitis media
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