Gram Negative Cocci Flashcards
Neisseria General
shape, requirements
G- diplococci (bean shaped)
Usually capnophilic, best in humid environment
Fastidious if pathogenic
Neisseria Gonorrhoeae Background
where, transmission, clinical
Habitat: NOT normal flora, mucous membranes, conjuctiva
Transmission: person to person, only human natural host
Clinical significance: sexually transmitted, conjuctivitis
Neisseria Gonorrhoeae Virulence Factor
4
- Capsule to resist phagocytosis
- Pilus for attachment
- Lipooligosaccharide (LOS) endotoxin
- IgA protease that releases enzyme to destroy IgA1
Neisseria Gonorrhoeae Infections
Local, systemic, vertical trans, other
Local
- GI tract infection, inflammatory disease and reproductive organs
Systemic
- Skin lesions
- Endocarditis
- Leading cause of purulent arthritis
Vertical transmission
Infected mother to baby
during childbirth
Other
- Septicemia and infection of skin, joints in some women, results of untreated
Gonorrhea: The Clap
Women
- Higher chance of getting it
- More asymptomatic carriers
Men
- Lower chance of getting it
- Initially asymptomatic mostly
Purulent discharge
- Untreated can lead to carrier state, major reservoir is the carrier
Neisseria Gonorrhoeae Antimicrobial Resistance
what is an effective one
Progressively gained resistance to each new antibacterial agent
- 1 last recommended anf effective one is: cephalosporins
Neisseria Meningitidis Background
Where, trans, clinical, virulence
Habitat: oral, nasoph. mucus membranes, may not cause infection - carrier state
Transmission: person to person, throat secretions, children, teens, YA, 65 or older at risk, human host
Clinical: meningitis, meningococcemia
Virulence: structures like NEGO, polysaccharide capsule, causes increase in production of capsule in high temps
Neisseria Meningitidis: Meningitis
what, symptoms
Inflammation of layers of meninges
- Will see microbes in CSF
Symptoms: stiff neck, headache, light sensitivity, altered mental state, nausea
- In babies: fever, high-pitched cry, doesn’t like being moved, soft spot in skull
How Neisseria Meningitidis Travels To Brain
3 ways and why
Transcellular: travels right through cells
Paracellular: travels between cells
Trojan horse: from within phagocytes traveling through
It can do these because of capsule that masks the cell surface
Neisseria Meningitidis: Meningococcemia
Septicemia with/without meningitis
Clinical features
- Thrombosis, multiorgan involvement
- Petechial skin rash, trunk and lower extremities
- Can spread rapidly, DIC and shock
Other Neisseria Species
where, trans, clinical
Habitat: normal flora of URT
Transmission: endogenous, maybe person to person
Clinical: rare, low virulence
Moraxella Catarrhalis Background
Where, trans, clinical
Habitat: normal flora of URT, sometimes female genital tract
Transmission: endogenous, person to person
Clinical: U and L RT infections, rare disseminated disease
Moraxella Catarrhalis Infections
Third most common cause of otitis media and sinitus in children
Lower RT infections: elderly, chronic pulmonary diseases
Aspiration pneumonia: particles from mouth constantly aspirated into airways, causes inflammation or infection in lungs
Treatment and Prevention for Neisseria and Moraxella
- Antibiotics
- Postexposure prophylaxis for NEME, 24 hours
- Vaccine for NEME groups A, C, Y, W-135
- Droplet precautions
- Serogroup B meningococcal vaccine
Specimen Collection
- Pathogenic Neisseria can dry out, temp sensitive
- Flocked swab for NEGO
- CO2 enriched, or transport media
- Culture within 6 hours