Term
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Definition
-bean shaped diplococci -gram negative -comensal to upper resp. and alimentary tract. Of interest to (and found only in) man: N. gonorrhoeae and N. memingitidis |
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Term
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Definition
-commonly found in nasopharynx -asymptomatic carriage in 15-25% of young adults -transmission is by saliva, droplet spread, etc -13 known serotypes -most common serotypes are A, B, C, Y, W-135 and X Gram negative, Oxidase postive
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Term
| Virulence of Neisseria meningitidis cell wall components |
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Definition
capsular polysaccharides -these resist neutrophil phagoctyosis Outer Membrane proteins -pilil facilitate adhesions -Opc is an OMP involved in attachment -PorA and PorB activate immune cells and induce formation of bacterial antibodies.
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Term
| Other Neisseriae virulence mechanisms |
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Definition
IgA protease -cleaves IgA, depressing immunity Iron extraction - can extract iron in an iron restricted enviro. Lipid A endotoxin - involved in induction of sepsis |
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Term
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Definition
-poorly teethered to the cell wall (of Neiserria) - as a result, often is shed releasing an endotoxin -endotoxin interacts with the monocytes, triggering cytokine release, resulting in inflammation and thus damage to organs.
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Term
| Entry of meningococci into blood stream |
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Definition
-in the upper respiratory tract via the non-ciliated mucosal cells. -then to the submucosa and then blood stream
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Term
| Two outcomes of a Neisseria meningitidis infection |
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Definition
a. Slow bacterial multiplication -local infection of meninges is most common b. Rapid bacterial multiplication in blood vessels -purpura, petechiae, shock....
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Term
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Definition
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Term
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Definition
| broken blood vessels under the skin |
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Term
| Clinical features of neisseria meningitidis |
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Definition
-endotoxin release causes blood vessel destruction -clinically, this is seen as a non-disappearing petechial rash -can also get gangrene due to coagulation w/i BVs -intraocular haemorrhage is also seen
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Term
| High Risk groups for Neisseria meningitidis |
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Definition
-infants aged 6 months to 2 years -people in overcrowded enviros like army recruits
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Term
| Fulminant meningococcemia |
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Definition
aka. Waterhouse friderichesen syndrom -adrenal gland failure due to bleeding into the A.G. -caused by severe meningococcal infection -death can occur within hours
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Term
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Definition
-N. meningitidis infection begins in the choroid plexus lining the ventricles -meningococci enter the subarachnoid space -get bacterial growth and inflammatory response due to endotoxin -use chocolate agar to culture meningococcal from blood
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Term
| Treatment of Neisseria meningitidis |
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Definition
-second generation cephalosporin or -penicillin G (in some cases)
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Term
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Definition
-gram negative coccus, non motile, non spore forming -usually seen in pairs -second most common STD
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Term
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Definition
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Term
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Definition
-high incidence in developing countries -4% of newborns there have ophthalmia neonatorum -transmitted more efficiently from men to women (at 40-60% efficiency rate for women after 1 exposure)
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Term
| Gonorrhoeae Virulence Factors |
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Definition
-has changing antigens to protect from antibodies -fimbrae for attachment to mucosa -Opacity associated protein important in adherence -Porin for penetration of host cells -Lipid A which has a signficant endotoxic effect -IgA proteases to cleave IgA
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Term
| Gonoccocal infections in males |
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Definition
-acute urethritis is most common -some remain asymptomatic (even after 2-7 days of incubation period) -some get painful urination or thick yellow pus in urine |
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Term
| Gonococcal infections in Women |
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Definition
-urethritis (often asymptomatic)
-burning sensation during urintation (less common) -cervicitis - pain w/ sexual intercourse and purulent vaginal discharge
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Term
| Complications of gonorrhoeae in women |
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Definition
-Pelvic inflammatory disease, ectopic pregnancies, peritonitis. -can also be passed on to their offspring (causing complications such as conjunctivitis in the child)
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