microbiology ch14 ( neisseriaceae, veillonella, parvobacteria, capnocytophaga Flashcards
(25 cards)
2 pathogenic genera of Neisseriaceae
Neisseria, Moraxella
Neisseria include
Ngonorrhoeae-most frequently diagnosed veneral disease in w. europe and usa. It causes PID, sterility in woman and arthritis and sptecemia
N. meningitidis- causes meningococcal meningitis which is highly contagious and kills up to 80%
Neisseriaceae are capnophillic which means
require more CO2 for growth
N Gonhorrhoeae
genital tract, oral, nasopharyngeal, rectal carriage, gram neg.
describe N gonhorrhoeae’s pathogenicity
Pili for adhesion
IgA proteases ( some)
Beta lactamase- beta lactam drugs are ineffective
tracheal cytotoxin- damages ciliated cells of the fallopian tubes causing sterility
neisseria meningitidis
nasopharynx, spreads to blood stream and meninges in susceptible people. treated with penicillin or cefotaxime
non pathogenic neisseria include…
n. subflava, n. mucosa, n sicca
whats the difference between non pathogenic and pathogenic neisseria?
non pathogenic neisseria can develop on agar in absence of CO2
Neisseria species in Dental field
Neisseria species are among earliest colonizers of clean tooth surface. They consume oxygen during the early plaque formation and facilitate subsequent growth of facultative and obligate anaerobic late colonizers
Moraxella
gram neg., closely related to neisseria species, respiratory tract, cause meningitis, endocarditis, otis media, most produce beta lactamse which can indireclt protect other pathogens
veillonella in general
gram negative, is oral samples
veillonella parvula
gram neg, in oral cavity and mostly in dental plaque, metabolize lactic acid produced by cariogenic bacteria into weaker acids with reduced ability to solubilize enamel
Parvobacteria
Gram neg. , include haemophilus, brucella, bordatella, pasteurella, francisella, gardnerella, eikenella
Haemophilus
Requires X and V factors to grow, causes bronchitis, epiglottitis, meningitis, sinusitis, otis media, osteomyelitis, arthritis
what is X and V factors?
X- haematin present in blood
V- nicotinamide adenine dinucleotide ( NAD), or NAD-phosphate which is a vitamin produced as a metabolic product of most bacteria
Haemophilus influenzae
upper respiratory tract, gram neg., virulent strains have capsules, requires V and X factors, causes meningitis, acute epiglottitis, osteomyelitis, arthritis, Treated by ampicillin,
Haemophilus influenzae shows satellitism. What is this?
where it grows around other bacteria that are producing V and X factors
virulence factors of haemophilus influenzae
polysacharide capsule, IgA protease which slows and causes incoordination of ciliary action of respiratory tract
Bordetella pertussis
upper respiratory tract of diseased folks,( not in healthy people),causes whooping cough, treated by erythromycin, antibiotics have little effect but can help reduce spread
what medium is used for bordetella pertussis?
gengou medium, blood charcoal agar supplemented with antibiotics for growth
Aggregatibacter actinomycetemcomitans
oral cavity, periodontal disease, subgingival sites, gamma haemolytic, grows best aerobically with 5-10% carbon dioxide, Treated with tetracycline
what are the virulence factors of a. actinomycetemcomitans?
endotoxin, leukotoxin, collagenase, cytolethal distending toxin, epitheliotoxin, protease cleaving IgG
what does leukotoxin do?
it subverts the host immune response in the gingival crevice
Eikenella
found in oral cavity and intestine, capnophilic, gram negative
