neisseria and hemopillus-bortadella Flashcards
Neiserria characteristics: gram+ or -?
Shape and arrangement?
oxidase + or -?
Gram-
kidney bean diplococci
oxidase +
Neiserria Meningitidis virulence factors?
growth medium?
Capsule and LPS (endotoxin)
Glucose, maltose, and blood agar
Neiserria gonorrheae virulence factors?
growth medium?
pili and OMPs
glucose only
Neisseria meningiditis: how many serogroups?
who is at risk?
when do you give vaccine?
13 serogroups
children, college students, military, gay men (outbreaks are sporadic but still a concern)
vaccinate at 11-12yo, booster before college, then for those at risk
Neisseria meningiditis: main virulence factor?
How does it get into humans (steps)?
How does it effect humans?
Capsule (prevents opsonization)
adherence in nose, transverses the cell, gets into blood stream, then crosses BBB
causes meningitis and severe sepsis (shock)
how do you treat it?
what agents prevent it? (aside from vaccine)
Ciftriaxone (cephalosporin is the best because it crosses BBB). can also use penicillin because resistance is low.
Ciprofloxacin and rifampin are other antibiotics that can prevent it (secondary prophylaxis)
Neiserria gonorrheae: main virulence factor?
how does it avoid HD?
How is it detected?
adhesins: Pili and Opa
antigenic diversity: pili recombination and Opa (can turn on and off)
gram stain (more sensitive in men), PCR (best is urine sample), and culture
N. gonorrheae: how is it passed? how does it invade? where does it effect? Where can it spread? How can it be treated?
sexual contact
invades same as meningiditis
Urethra, cervix are main sites of clinical manifestation
can spread throughout the body via blood (joints, skin)
Ciftriaxone (resitant to oral), normally combined with azithromycin or doxycycline in case of co-infection with chlamydia trachomatis
Haemophilus: size, shape, gram+ or -?
Main virulence factor?
main species?
tiny/small gram- coccobacilli
capsule
H influenza
encapsulated vs unencapsulated H Flu?
encapsulated: meningitis, epiglotitis, cellulitis, sepsis, arthritis
unencapsulated: otitis media, sinusitis, bronchitis
H flu growth culture?
chocolate agar with V and X growth factors from blood
How is H flu treated?
Severe disease: cephalosporin
Less Severe: azithromycin, fluoquinolones
Bordetella: size, shape, gram+ or -?
virulence factors?
gram- tiny coccobaccili
adhesins: pertactin and Fha (both bind glycoproteins, integrins in reap cells, CR3 in macrophages to allow survival)
Toxins: pertussis toxin and tracheal cytotoxin
Pertussis Toxin components (and function)?
A: enzymatic portion, ADP ribosylation to prevent inactivation of AC, thereby constantly increasing cAMP (increases mucus secretions and lymphocytosis)
B: binding portion (binds cilited resp cells and phagocytes)
Tracheal cytotoxin: what is it? what does it cause?
Fragment of peptidoglycan causes damage to resp cells)