corynlistnocardiaactino Flashcards
Corynebacterium diphterhiae
ABCDEFG
A: ADP ribosylation B: B prophage C: Corynebacterium D: Diphteriae E: Elongation Factor 2 G: granules
Gram + rod transmitted via resp droplets in se asia
corynebacterium diphterhiae
C. diphterhiae potent extoxin function
inhibits protein synthesis via ADP-ribosylation of EF-2
causes diphteria via exotoxin encoded by
B prophage
Pseudomembranous pharyngitis (grayish-white membrane w lymphadenopathy, myocarditis, and arrhytmias)
C. diphterhiae
Lab diagnosis of C diphterhiae
gram + rods w metachroomatic (blue and red) granules and + Elek test for toxin
what color are the granules in c diphterhiae
blue and red
Stain the metachromatic blue and red granules with
aniline dyes
how does toxoid vaccine prevent diphterhia
neutralizies IgG antibodies against binding component (B subunit) of diphterhia exotoxin)
when dealing with C. dificile what should you do
gown, nonsterile gloves
handwashing aw soap and water (alcohol based hand sanitizers) do NOT kill spores
on the cytsine-tellurite agar what color for C. diphteriae
black colonies
severe pharyngitis w exudates and cervical lymphadenopathy in a group of people with unknown vaccination statsu
resp diphteria infection; diphteria toxin: severe myocarditis and heart failure
function of A (active subunit ) of diphteriha AB exotoxin
transfer ribose residue from NAD to a histidine on EF-2; essential for peptide chain translocation on ribosome in process of translation
lysogenic bacteriophage called corynephage beta converts
nontoxigenic to toxigenic C. diphterhia due to infection
lysogenic bacteriophage inserts tox gene into genome: resulting in
expression of dipstheria AB toxin.
B subunit of diphtehria AB exotoxin binds to
heparin-binding epidermal growth factor receptor on cardiac + neural cells
intracellular pyrophosphate granules of c. diphterhiae visualized on microscopy after growing pathogen on
Loeffler medium - stain w mehtylene blue
rare in developed countries
narrow zone of beta hemolysis
listeria monocytogenes
faculattive intracellular rod; aerobic
listeria
acquired by ingestion of unpasteruized dairy products and cold deli meats, via transplacental transmission, or by vaginal transmission during birth
listeriaa
growsh well at refrigeration temps (4-10 C): cold enrichment
listeria
rocket tails via actin polymerization allow interacellular movement and cel to cell spread across cell membranes; thereby avoiding antibody
listeria
tumbilng motiliy at room temperature
listeria
what does listeria cause
amnionitis, septicemia, spontaneous abortion in pregnant women; granulomatosis infantiseptica; neonatal meningits; meningits in inmmunocomporsied pt’s ; midl , self limited gastroentertitis in healthy individuals
listeria can be trasnimitted (pregnant)
transplacenntally or via vaginal contact during delivery causing neonatal menignits
in pregnant woemen, listeria causes greates risk in
3rd trimester; can cause preterm labor, neonatal sepsis
why is nocardia weakly acid fast
has mycolic acid in cell wall
where is nocardia found
in soil; disease from spore inhalation or traumatic inoculation into skin
where is actninomyces found
normal oral , reproductive, GI flora, colon
actinomyces is acid fast or no
not acid fast
causes pulmonary infections in immunocomporomised (can mimic TB but w - PPD)
nocardia
causes cutanoeus infectison after trauma in immunocompetent; can spread to CNS to cause brain abscesses ; seizures
nocardia
Treatment is SNAP
sulfonamdies: nocardia
Actinomuces: penicillin
oral/facial abscesses that drain thorugh sinus tracts
actinomyces