microbiology Flashcards
spore
gram + only
capsule
polysaccahride (except bacillus anthracis which is poly d glutamate)
pleomorphic
means no cell wall
anaplasma, ehrlichia
chlamydiae (giemsa)
rickettsiae (giemsa)
mycoplasma (has sterols which dont gram stain)
borrelia
(giemsa)
coccus
spherical
streptococcus
chains or pairs
entercoccus
pairs or short chains
moraxella catarrhalis taxonomy/morphology
gram negative spherical (coccus)
corynebacterium morp
gram + rod
clostridium morph
gram + rod
gardnerella morph
gram variable rod
lactobacillus
gram + rod
listeria morph
gram + rod
mycobacterium morph
acid fast rod
propionibacterium morph
gram + rod
fusobacterium morph
gram - rod
bordetella
respiratory gram negative coccobacillius
burkholderia cepacia
gram negative rod respiratory
haemophilus
gram negative coccibacillus (pleomorphic) respiratory
legionella
silver stain rod (gram negative?) respiratory
bartonella
gram negative zoonotic
brucella
gram negative coccobcaillus zoonotic
francisella
gram - zoonotic coccobcaillus
pasteurella
gram - zoonotiv coccobcaillus
poor gram stain
these little microbes may unfortunately lack real color but are everywhere
treponema, leptospira (too thin), mycobacteria (lipid content), mycoplasma, ureaplasma (no cell wall), legionella, rickettsia, chlamydia, bartonella, anaplasma, enrlichia (primarily intracellular, plus chlamydia lacks classic peptidiglygan due to decreased muramic acid)
giemsa stain
certain bugs really try my patience
chlamydia, borrelia, rickettsia, trypanasomes, plasmodium
ziehl neelsen stain (carbol fuchsin)
protozoa (eg cryptosporidium cysts)
cryptococcus neoformans detection
culture on sabouraud agar, india ink (clear halo), mucicarmine (red inner capsule). latex agglutination assay detects polysaccharide capusle and is more specific.
silver stain
fungi eg (coccidioides, pneumocystis), legionella, helicobacter
n meningitidis culture
thayer martin
thayer martin contents
vancomycin against gram +, trimethoprim and colistin and fungi with nystatin
Very typically cultures neisseria
c diptheriae culture
tellurite and loffler (enhances metachromasia)
m pneumoniae
eaton with cholesterol
e coli culture
eosin methylene blue agar, colone with green metalic sheen
fungi culture
sabouraud
aerobe examples
nocardia, pseudomonas, mycobacteria,
naggin pests must breath
anaerobes examples
clostridium, bacteroides, fusobacterium, actinomyces
cant breath fresh air
why are anaerobes susceptible to oxidative damage?
lack catalase and or superoxide dismutase
anaerobes general features
foul smelling (short chain fatty acids), difficult to culture, and produce gas in tissue (co2 and h2)
normal flora in the gi tract, pathogenic elsewhere
facultative anaerobes examples
streptococci, staphylocci, and eneteric gram +
obligate intracellulars
rockettsia, chlamydia, coxiella. rely on host atp. stay inside cells when its Really CHIlly and Cold
faculatative intracellulars
salmonella, neisseria, brucella, mycobacterium, listeria, francicella, legionella, yersinia pestis
Some nasty bugs may live FacultativeLY
encapsulated bacteria
pseudomonas, streptococcus, haemophilus, influenza type b, neisseria meningitidis, e coli, salmonella, klebsiella, groub B strep
please SHINE my SKiS
pneumococcal vaccines
pcv13 conjugate. ppsv23 not conjugated
h influenza vaccine
conjugate
meningococcaly vaccine
conjugate
urease positive organisms
proteus, ctryptococcus, h pylori, ureaplasma, nocardia, klebsiella, s epidermis, s saprophyticus.
Pee CHUNKS
catalase +
nocardia, pseudomonas, listeria, aspergillus, candida, e coli, staphylocci, serratia, b cepacia, h pylori
CATs need placess to Belch their Hairballs
s aureus pigment
yellow
pseudomonas pgiment
blue green (pyocyanin and pyoverdin)
serratia marcescens
red pigment
biofilm makers
s epidermididis, viridans (s mutans and s sanguinis), p aeruginosa, nontypeable (unencapsulated) h influenza
s epidermidis charch
catheter and prostehtic devices
viridans (s mutans and s sanguinis)
dental plaques and infective endocarditis
p aeruginosa
respiratory tree colonization in CF pts, ventilator assisted pneumonia, contact lens associated keratitis.
type 3 secretion system
also known as the injectisome. needle like appedage faciliatating direct delivery of toxins from certain gram - to eukaryote cells.
psudomonas, salmonella, shigella, e coli.
transformation bugs
ShIN
s pneumoniae, h influenza, neisseria
lysogenic phage toxins
ABCD’S
group A strep erythrogenic toxin, botulinum toxin, cholera toxin, diphteria toxin, shiga toxin
endotoxin/exotoxin feature: source
exotoxins are made by gram + and - endotoxin gram - only
endotoxin/exotoxin feature: chemistry
exotoxins are polysaccharide
endotoxin/exotoxin feature: location of genes
exotoxin plasmid or bacteriphage
endotoxin bacterial chromosome
endotoxin/exotoxin feature: adverse affects
exotoxin
high (fatal dose 1 uq)
endotoxin low 100s uq
endotoxin/exotoxin feature: clinical affects
exotoxin various
endotoxin fever, shock (hypotension), dic
endotoxin/exotoxin feature: mode of action
exotoxin various
endotoxin induce tnf il1 il6
endotoxin/exotoxin feature: antigeniticty
exotoxin induces high titers called antitoxins
endotoxin is poorly antigenic
endotoxin/exotoxin feature: vaccines
exotoxin toxoids used as vaccines
endotoxin no toxoids
endotoxin/exotoxin feature: heat stability
exotoxin destroyed rapidly at 60 degrees c (except staph enterotxin and ecoli heat stable toxin)
endotoxin
stable at 100 degree c for 1 hour
endotoxin/exotoxin feature: typical diseases
exotoxin tetanus, botulism diptheria,
meningococcemia; sepsis by gram - rods
diptheria toxin
(inhibit protein synthesis)
inactivates ef-2 (vs e2f) sounds like blocks peptide elongation
adp
ab
exotoxin A
(inhibit protein synthesis)
pseudomonas
inactivation of ef-2 vs e2f, results in host cell death
adp
ab
shiga toxin (ST)
(inhibit protein synthesis)
inactivate 60s ribosome by removing adenine from rRNA
mucosal dmage -> dystenery
enhances cytokine release -> HUS
ab
shiga-like toxin (verotoxin)
(inhibit protein synthesis)
unlike shigella, ehec does not invade
cytokine release -> HUS
a
heat labile toxin (LT)
(increase fluid secretion)
etec
activates camp -> increased CL secretion and water efflux
adp
ab
heat stable (ST)
(increase fluid secretion)
etec
overactivates guanylate cyclase -> increased cgmp - decreased nacl reabsorbtion and water
edema toxin
(increase fluid secretion)
B anthracis
minis adenylate cylase (increased camp)
likely responsbile for the charateris edematous borders of black eshcar in cutaneous anthrax
ab
Cholera toxin
(increase fluid secretion)
overativates adynalte cyclase by permenately activating gs. increased cl sectiona nd h20 elffux.
voluminous rice water stools
ab
pertussis toxin
(inhibit phagocytic activity)
overativates adynalte cyclase by impairing gi -> increased camp. impairs phagocytosis to improve survival of microbe.
ab
adp
tetanospasmin
ab
is a protease. works on snare (soluble NSF attachment protein receptor)
botulinmu toxin
protease working on snare (soluble nsf attachment protein receptor)
ab
Alpha toxin
(lyse cell membranes)
C perfingens
Phospholipase (lecithinase) that degrades tissue and cell membranes
degradtion of phospholipids -> myonecrosis (gas gangrenes) and hemolysis (double sone of hemolysis on blood agar)
Streptolysin O
(lyse cell membrane)
protein that degrades cell membranes
lyses RBS, contributes to the B hemolysis. Host abs agaisnts ABOs used to diagnosis rheumatic fever.
toxic shock syndrome toxin (TSST-1)
super antigen
binds mhc2 and tcr and causes il1 il2 ifn g tnf a release -> shock
toxic shock syndrome: fever, rash, shock
exfoliative toxin causes scalded skin syndrome and bullous impetigo.
heat stable enterotixin.
erythrogenic toxins a and b (spea and speb)
strep pyogenes
binds mhc2 and tcr and causes il1 il2 ifn g tnf a release -> shock
toxic shock like syndrome; fever rash shock
scarlet fever
endotoxin tlr4 activation
il 1, il-6, -> fever
tnf a -> fever and hypotension
nitric oxide -> hypotension
endotoxin complement activation
c3a and c5a histamine release and hyptension
c5a nutrophil chemotaxis
tissue factor activation by endotoxin
coagulation cascade -> dic -> renal failure
catalase postive respiratotion
anaerobic/facultative
gram positive color
purple/blue
gram + bacilli aerobic
LBC
listeria, bacillus, corynebacterium
gram + bacilli anaerobic
clostridium propionibacterium
B hemolytic PYR positive
group a strep
viridans 2 species and characteristic
s mutans and s mitis (unencapsulated)
a hemolytic description
greenish or brownish colow without clearing
b hemolysis
shows clear area
includes: Staph strep pyogenes strep b listeria
protein A of staph inhibits?
compliment activation and phagocytosis
s aureus colonizes
nares, axilla, groin
2 inflammatory s aureus
septic arhtisis and osteomyelitis
toxic shock syndrome
fever, vomiting, rash, desquamation, shock, end organ failure
increased ast, aslt , bilirubin
Can also be caused by nasal packing
cause of toxic shock like syndrome?
painful skin lesion
s aureus enteroxin feature
heat stable, not destroyed by cooking
coagulase of staph
helps it form a fibrin clot around itself
staph aureus ferments
manitol
s epidermidis infects
iv catheters, heart valves, prosthetic devices by forming biofilms
strep pneumoniae otitis media
in children
viridans group that cause dental caries
strep mutans and s mitis
viridans that causes endocarditis
s sanguinis
s sanguinis virulence
makes dextrans that allow binding to fibrin platele aggregates
group b strep causes
pneumonia, sepsis, and meningitis in babies
fxn of group b camp factor
enhances area of hemolysis by s aureus
strep bovis and extra name and one thing it can cause
S gallolyticus (s bovis biotype 1)
bactermia and subacute endocardits in colon cancer
entercocci
subacute endocarditis
pyr +
variable hemoylysis
VRE are important nosocominal bugs
bacillus anthracis
spore forming
bacillus anthracis morphology
colonies show a medusa head which is a halo of projections around themselves
cutaneous anthrax
classically hide of goat (craftsmen)
painless papule surrounded by vesicles -> ulcer with black eschar (painless, necrotic)
pulomnary anthrax
inhalation of spores -> flu like symptoms -> rapidly fever, pulmonary hemmorhage mediastinitis (macs took them) and shock.
b cerueus causes
food poisoning
b cerueus pathogenesis
keeping rice warm results in germination of the sporesand enterotoxin formation called (cereulide)
b cerueus emetic type associated with?
rice and pasta n/v within 1-5 hours, cereulide involved
diarrhea type b cerueus
watery and gi pain within 8-18 hrs
c tetani causes
trismus (lockjaw), risus saronicus (raised eyebrows and open grin), opisthotonos (spasms of spinal extensors)
c tetani treatment
prevent with vaccine. treat with antitoxin +/- booster, diazepam for spasms, wound debridement
c botulinum toxin feature and mech
heat labile prevents ach from being released -> flaccid paralysis
fourd d’s of botulinum
dysphagia, diplopia, dysathria, dyspnea.
c botulinum how adults get
ingesting preformed toxin
c botulinum kids
floppy baby syndrome from ingesting spores in honey
c botulinum can treat
dystonia, achalasia, muscle spasms and facial wrinkles
c perfingens toxin
alpha toxin (lechithinase, a phospholipas) that causes myonecrosis (gas gangrene) and hemoylsis
other thing c perfingens can do
spores survive in undercooked food and whn ingested bacter release heat labile entertoxin -> food poisoning
c diff toxins
toxin a -> binds bursh border and alters gut fluid secretion
toxin b -> a cytotoxin, disrupts cytoskeletan by actin depolymerization
both lead to diarrhea -> pseudomembranous colitis
c diff can be causes by?
clindamycin, ampicillin, ppi
c dfif diagnosis?
one or more toxins in the stool by PCR
c dip agars
cystine-tellurite agar grows black colonies
i think lofflers causes the blue and red metachromatic granules
c dip lab test
elek test positive for toxin
c dip exotoxin encoded by?
b prophage
c dip toxin mech
inhibits protein synthesis by adp ribosylation of ef 2
c dip clinical
bull neck, myocarditis, arrythmias, neuro symptoms
listeria living
facultative intracellular
c dip transmission
respiratory droplets
listeria get from?
unpasteruizeddairy products and cold deli meats, via placental transfer, vaginal transmission during birth
listeria growth
grows well at refrigeration temps ( 4 - 10 degree cold enrichment)
listeria movement
“rocket rails” from actin polymerization that allow cell to cell and intracellular movement
saying intracellular it avoids abs
tumbling motility in broth
listeria clinical
amnionitis, septicemia, and spontaenous abortion in pregnant women
meningitis in immunocompromised
self limited gastroenterits in immunocompotent adults
nocardia vs actino where found?
soil vs normal oral, reproductive, and gi flora
nocardia clinical
pulmonary infection in immunocompromised (can mimic tb but negative ppd), cuteaneous infection in immmunocompotent after trauma, can spread to cna
actino clinical
causes oral/facial abscess that drain through sinus ttracts.
associated with gental caries/extraction.
forms yellow sulfur granules
PID with IUDs
PPD +
current infection or past exposure
IGRA advantage
fewer false positive
what is a ghon complex
ghon focus + hilar lymph nodes
where can miliary TB spread to?
meningitis, vertebrae (pott disease), lymph nodes, spleen, liver, adrenal glands
cord factor
creates a serpitine cord appearence where virulent m tuburculosis strains line up
activates macs (promoting granuloma formation) and induces release of TNFa
sulfatides (surface glycolipids)
inhibit phagolysosome formation
m scrofulaceum
cervical lymphadenitis in children
m marinum
hand infection in aquarium handlers
all mycobacteria are acid fast, which means?
they stain pink
m leprae infects
skin and peripheral nerves, likes cook temps
m leprae sensation loss?
glove and stocking
m leprae labs
cannot be grown in vitro
diagnosed via skin biopsy or tissue PCR
m leprae resevori in US
armadillos
lepromatous form
presents iffusely over the skin, with leonine (lion like faces), and is communicable.
low cell mediated immunit with humoral th2 response
tuberculoid form
limited to a few hypoesthetic (decreased sensatoin), hairless sking plaques
high th1 response
gram negative diplococcis aerobic with maltose utilization
n mengitidis
gram negative diplococcis aerobic without maltose utilization
n gonnorhea or moraxella
gram negative stains?
pink
gram negative coccobacilli
h influenza
bordetalla pertusiss
pasteurella
brucella
franscilla
(all zoonotic, bartonella also a zoonotic but not coccobacilli gram - rod)
coma shaped oxidase positive
campylobacter jejuni (42 degree growth)
vibrio (grows in alkaline media)
helico (produces urease)
b henslae
gram - rod
b fragilis
gram - rod
gram - baccili lactose fermentation +
fast
kleb
e coli
entero
slow
citrobacter
serratia
gram - baccili lactose - oxidase +
pseudomonas
gram - baccili lactose - h2s production on TSI agar +
salmonella, proteus
gram - baccili lactose - h2s production on TSI agar -
shigella yersinia
how does e coli ferment lactose?
with b galactosidase that break lactose inro glucose and galactose
EMG agar
lactose fermenters grow as purple/black colonies
e coli grows colonies with a green sheen
neisseria fermentation
both ferment glucose
only meningoccis ferments maltose
conococci shape
kidney bean shaped
does gonococcis have a capsule?
no
menigigoccia causes
causes meningococcemia with petechial hemmorahges and gangrene of toes, meningitis, waterhouse frerichsen sydnrome (fever, adrenal inusfficiency, DIC, shock)
h influ how transmitted?
aerosol
h influ non typeable (unencapsulated causes)
mucosal infections (otitis media, conjunctivits, bronchitis) as well as invasive disease since vaccine agaisnt type b.
h influ virulence
iga protease
h influ grows on?
chocalate agar (contains 5 and 10) and can also be grown with s aureus which provides factor 5 through hemolysis
h influ can also cause?
pneumonia
h influ vaccine?
polyribosylribitol phosphate conjugated to diphteria toxoid
when to give h flu vaccine?
2 and 18 onths
signs of epiglottis
stridor, thumbprint sign, cherry red appearence
bordetella pertussis virulence factors
pertussis toxin (diasbles Gi increasing camp) and tracheal cytotoxin
bordetella pertussis stages
catarrhal - low grade fevers, corza (rhinits, runny nose)
paroxysmal stage (100 day cough) - paroxysms of intense cough follow by whoop, posttussive vomiting
convalescet phase - gradual recover of cough
pertussis toxin can causes
lymphocytosis, hypoglycemia
vaccines for bordetella
Tdap, DTaP
bordetella what can it be mistaken for?
a viral infection due to lymphocytic infiltrate resulting from immune response
bordetella agar
bordet gengou
legoinella culture
charcoal yeast extract with iron and cysteine
legoinella detection?
antigen in urine
legoinella transmission
aerosol from encrionmental sources (ac systems, hot water tanks)
no person to person transmisson
legionnaires disease pneumonia type
often lobar and unilateral
legionnaires disease symptoms
fever, gi, and cns symptoms
legionnaires disease common in?
smokers and in chronic lung disease
pontiac fever
mild flu like syndrome
pseudomonas morphology
aerobic and motile
pseudomonas produces?
pyocyanin which is a blue green pigment and has a graplike odor
pseudomonas virulence
produces endotoxin (fever, shock), exotoxin A (inactivates ef-2), phospholipase C (degrades cell membrane), pyocyanin (generates ROS)
pseudomonas causes
PSEUDOMONAS
P - pyocyanin, pneumonia S - sepsis E - ecthyma gangrenosum U -UTIs D - diabetes, drug use O - osteomyelities (puncture wounds) M - mucoid polysaccharide capsulre O - otitis externa (most common overall) N - Nosocominal infections (catheters, equipment) A - Exotoxin A S - skin infections - hot tub folliculits
pseudomonas and IV drug users
right sided endocarditis
pseudomonas psteomyelitits
daiabetic foot ulcers, moist shoe puncture
pseudomonas feared complications of burns
burns are good environment, worry about sepsis
sepsis in?
neutropenia, diabetics, extensive burns, leukemia
why do cycstic fibrosis patients get chronic penumonia?
because of the mucoid polysacharide capsulre forms biolfilms
pseudomonas think andy
corneal ulcers/keratitis in contact lens wearers /minor eye trauma
ecthyma gangrenosum
rapidly progressive necrotic cutaneous lesioin, caused by pseudomonas bactermia, typically in immnocompromised
fever prior
single or multiple lesions
e coli virulence factors
fimbriae - cystitis and pyelonephritis (p pili); k capsule - oneumonia and neonatal meningitis; LPS endotoxin - septic shock
EIEC
invades intestinal mucosa, causes necrosis and inflammation
invasive; dysentery. clinically similar to shigella
ETEC
produces heat labiile and heat stable toxin; no inflammatin of invasion
travelers diarrhea
EPEC
no toxin produced. adheres to apical surface, flattens villi, prevents absorption.
diarrhea in children
EHEC serotype
O157:H7 most common serotype in us
EHEC transmission
undercooked meat and raw leafy veggies
EHEC clinical
dysentery (toxin alone produces necrosis and inflammation)
EHEC labs
does not ferment sorbitol vs other e coli
EHEC toxin and what does it causes?
shiga like toxin and causes HUS
causes decreased renal blood flow
klebsiella flora?
intestinal
klebsiella causes?
lobar pneumonia in alcoholics and diabetics when aspirated
also noscocominal UTI
klebsiella morphology
mucoid colonies caused by abundant polysaccharide capsule
klebsiella sputum
dark red “currant jelly” sputum blood and mucous
kelbsiella 5 A’s
Aspiration pneumonia
Abscess in lung and livers
Alcoholics
diAbetics
campylobacter mmorphology
common or s shaped with polar flagella
campylobacter causes
bloody diarrhea, espiecally in children
campylobacter transmission
fecal oral from person to person, or ingestion of undercooked poultry or meat, unpastruerized milk.
contact with infected animals (dogs, cats, pigs)
campylobacter can causes
gullian barre and reactive arhtirits
how do salmonella and shigella invade?
via m cells of th epeyer’s patches
what do salmonella typhi, salmonella spp, and shigella infect?
humans, humans and animals, humans
what do salmonella typhi, salmonella spp, and shigella h2s productions
yes, yes, no
what do salmonella typhi, salmonella spp, and shigella flagella
yes, yes, not
what do salmonella typhi, salmonella spp, and shigella virulence
endotoxin; Vi capsule, endotoxin, endotoxin, shiga toxin (enterotoxin)
what do salmonella typhi, salmonella spp, and shigella id50
high (large incoulum required because gastric acid inacivates), high, low (very small inovulum required bc resistant)
what do salmonella typhi, salmonella spp, and shigella efftcs of antibiotics on fecal excretion
prolongs, prolongs, shortens
what do salmonella typhi, salmonella spp, and shigella immune response
monocytes, pmns, pmns
what do salmonella typhi, salmonella spp, and shigella gi manifestations
constipation; followed by diarrhea, diarrhea (possibly bloody), bloody diarrhea (bacillary dysentery)
what do salmonella typhi, salmonella spp, and shigella vaccine
only for s typhi, oral vaccine is live attenuated s typhi and IM vaccine contains Vi capsular polysaccharide
typhoid fever (enteric fever) cilnical manifestations
rose spots, constipation, abdominal pain, fever
s typhi unique property
can be carried in the gall bladder
salmonella non typhoidal species
poultry, eggs, pets, and turtles
salmonella non typhoidal usually causes?
gastroenteritis
salmonella non typhoidal antibiotics to treat
not indicated
shigella sources
fingers, flies, food, feces
shigella in order of decreasing severity
s dysenteriae (bacillary dysenteriae), f flexneri, s boydii, s sonnei (shigellosis)
shigella key fact
invasion of M cells is key to pathogencity and organisms froduce little toxin can cause disease
vibrio morphology
flagellated and comma shaped
vibrio culture
grows in alkaline media
vibrio infectvity?
sensitive to stomach acid, requires a large incodulum (high id50) unless host has decreased acid
vibrio transmission
transmitted by contaminated water or uncooked food (eg raw shellfish)
vibrio treatment
oral rehydration
yersinia enterocolitis tranmission
pet feces (eg puppies), contaminated milk, or pork
yersinia enterocolitis manifestations
acute diarrhea or pseudoappendicitis (right lower abdominal pain due to mesenteric adenitis and/or terminal ileitis)
h pylori moprhlogy
curved, flagellated
h pylori lab
triple positive cat, ox, urease
h pylori diagnosis
urea breath test or fecal antigen test
spriochetes visualization
only borrelia can be visulized by aniline dyes (wright or giemsa) due to its large size
treponema is visulzed by dark field microscopy or direct furescent ab (dfa)
leptospira interrogans morphology
hook shaped ends
leptospira interrogans transmission
water contamited with animal urine
leptospirosis
flu like symptoms, myalgias (especially calves), jaundice, photophobia with conjuntival suffusion (erythema without exudate). prevelant in surfers and in tropics (hawaii)
weil disease and aka
(icterohemorrhagic leptospirosis)
sever form of jaundice and azotemia from liver and kidney dysfxn, fever, hemorrhage, and anemia