• Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off
Reading...
Front

How to study your flashcards.

Right/Left arrow keys: Navigate between flashcards.right arrow keyleft arrow key

Up/Down arrow keys: Flip the card between the front and back.down keyup key

H key: Show hint (3rd side).h key

A key: Read text to speech.a key

image

Play button

image

Play button

image

Progress

1/15

Click to flip

15 Cards in this Set

  • Front
  • Back
Neisseria general features (shape, oxidase, O2 tolerance, tests, pathogenic species)
Shape - Gram negative diplococci that apear in pairs, kidney bean appearance.
Tests - Oxidase positive, strict aerobe, requires CO2 and enriched medium for growth (chocolate agar, Thayer-martin agar).
Species - N. gonorrhoeae, N. meningitidis
N. Gonorrhoeae Virulence factors
1) Pili - Major virulence factor, can change antigen to avoid immune system.
2) OMP 1 and 3 - Porins which inhibit compliment
3) OMP II - Promotes attachment to host, invaision of epithelial cells, and antigenic variation evades host
4) IgA protease - cleaves IgA1
N. Gonorrhoeae Pathogenesis
Primarily localized to mucosa, rare in blood or tissue
1) Pain and purulent discharge
2) Men: urethritis
3) Women: cervicitis, salpingitis, pelvic inflamatory disease which can lead to ectopic preg. or sterility
4) Rectal or pharyngeal infection
5) If in blood, fever, rash, polyarthralgia
6) Baby can get infected conjunctiva during birth = gonococcal ophthalmia neonatorum
N. Gonorrhoeae Diagnosis
1) Nucleic acid amplification. Not for children or monitoring ab resistance.
2) Culture in thayer-meyer and CO2, then IDed.
3) Males: Gram stain of urethral exudates showing gram neg. diplococci
N. Gonorrhoeae Treatment
Ceftriaxone (pen. resistance common). Also treat for chlamydia infection b/c co-infection is common.
N. Meningitidis Virulence Factors
1) LOS triggers TNF and IL-1 which induce shock
2) Capsule - Are antiphagocytic and immunogenic (except B capsule).
3) Pili
4) IgA proteases
Pili
Virulence factor. Made of peptides, enhance attachment to epithelia/mucossa preventing phagocytosis. Can express multiple different antigens of pili via "gene conversion" to evade immune system.
N. Meningitidis Diseases
1) Meningitis
2) LOS triggers TNF and IL-1 > shock
3) Also activates coagulation system causing disseminated intravascular coagulation (DIC) > abnormal bleeding and tissue damage.
4) Septicemia with petechial or ecchymoses rash
5) Hemorrhagic destruction of adrenal glands, circulatory collapse, death.
3-5 = waterhouse-friderichsen syndrome
N. Meningitidis Epidemiology (Who, how transmitted, when)
Who - Human are only natural host. 3-12 months of age highest risk
How - Person to person via respiratory droplets. Family contacts lacking antibodys are at high risk.
When - Most common in winter/early spring.
N. Meningitidis Diagnosis
Gram stain of CSF (presumptive)
Culture of CNF and blood. Requires chocolate agar and CO2 (definitive)
Grouping performed by slide agglutination test
N. Meningitidis Treatment
Ceftriaxone (most common used) Penecilin (resistance rare)
Prophylaxis - Rifampin, ciproflaxcin, ceftriaxone.
Vaccination for kids 2-10, adults >55
Gram (-) cocci: Main classes
Neisseriae
Moraxella
Acinetobacter
Moraxella catarrhalis (shape, oxidase, O2 tolerance, disease)
Gram (-) coccobacilli
Oxidase positive
Aerobic
Causes otitis media, pneumoniae, conjunctivitis and cnf/joint infections. Opportunistic
Acinetobacter (shape, oxidase, O2 tolerance, disease)
Gram (-) coccobacilli
Oxidase negative
Aerobic
Causes hospital-acquired infections, particularly ventilaror associated pheumonia. Oportunistic
N. Gonorrehoeae visible characteristics
Diplococcus
Gram neg
Pilliated
non-encapsulated
non-motile