Microbiology GM Positive Flashcards
Bordetella pertussis
Gram Negative Coccobacilli
transmitted by respiratory droplets or tocuhes surfaces
filamentous hemaglutinin, pertactin, agglutinin: anchor it to the epithelial wall
Tracheal cytotoxin: paralyzes cilia in respiratory tract\
pertussis toxin: also anchors it to epithellial and increases lymphocytes (tcell) in blood but blocks it from leaving the blood
adenylate cyclase toxin: blocks phagocytes to get ot the area and kills them
Sx: violent cough
What bugs do not take well to gram stains
These microbes may lack real color
Treponema Mycobacteria Mycoplasma, ureaplasma Legionella Rickettsia Chlamydia
What bugs use giemsa stain
Certain bugs really try my patience
Chlamydia Borellia Rickettsia Trypanosome Plasmodium
What bugs use india ink stain
cryptococcus
what bugs use silver stain
fungi
What grows on a chocolate agar
H. influenza
S. pneumoniae
What gros on thayer-martin agar
Niesseria
What grows on a regan-lowe medium
b. pertussis
What grows on loffler medium or tellurite agar
C. dipertheria
What grows on lowenstein-jensen agar
M. tuberculosis
what grows on eaton agar
m pnuemoniae
What are the encapsulated bacteria
Please SHINE my SKis
Psudomonas Streptocoocus pneumoniae Haemophilus Influenza Neiserria E. coli Salmonella Klebsiella Strep group b
Urease-positive organisms
Pee CHUNKSS
proteus crytococcus H pylori ureaplasma Nocardia Klebsiella S,eouderudus'S, saprophyticus
Catalase positive organisms
CATs Need PLACESS to Belch their Hairballs
Nocardia, Pseudomonas Listeria Aspergillus Candida Ecoli Staphyloccoci Serratia B cepacia H pylori
What is protein A and what organism
Staph aureus
binds to Fc region of IgG to prvent opsonization of phagocytosis expressed by s. aureus
Which bugs have IgA protease
S. pneumoniae and H influenza
Neisseria also
M protein
helps prevent pagocytosis. expressed by group a step
What are the spore forming bacteria
Baccillus and clostridium
Which Gm has a thicker cell wall
what color does it stain?
Gram positive
stains purple
What gm has large amounts of peptidoglycan cell walls
what is peptidoglycan
a starch
Gm +
What gm has walls containg lipolysaccharides
Gm -
What gm has endotoxin
what is the pneumonic
Gm -
Edema Nitric Oxide DIC/Death TNF-alpha O-antigen Xtremely heat stable Il-1 Neutrophil chemotaxis
where do you find LPS
gram -
Where do you find teichoic acid
gm +
What is catalase positive Staph or step
Staph
List the 3 mainGm + rod(baccili)
Clostridium
Listeria
Baccilis
What two specifics have partial hemolysis and are alpha hemolytic
S. pneumoniae
S. viridans
What are the main differences in s. pneumoniae and S. viridians
S. pneumoniae is optochin sensitive, bile soluble and has a capsule
S. viridians has no capsule, optochin resistant and is not bile soluble
What 2 bugs are clear hemolysis and beta hemolytic
s. pyogenes
s. agalactiae
What is the difference between S. pyogenes and S. agalactiae
S. pyogenes: group a strep, bacitracin sensitive
S. Agalactiae: group b strep, bacitracin resistant
what two bacteria do not undergo any hemolysis
enterocoocus and peptostreptococcus
Staphylocci are Gm +/-
what do they lack
Gm+
lack spores and flagella
What does coagulase do?
What organism is coagulase positive
Coagulase enables the conversion of fibrinogen to fibrin. Staph arueus has coagulase bound to cell surface and uses it to cover it’s surface with fibrin when in contact with blood. This may work to avoid phagocytosis. Can lead to abscess.
What are four virulence factors of S. aureus
- coagulase
- protein A
- beta hemolytic
- toxic shock syndrome toxin=super antigen
what dz can staph aureus cause
- localized cutaneous infections
- osteomyeltis, bacteremia, acute endocarditis
- food posioning
- scalded skin syndrome
- toxic shock syndrome
is S epidermidis coagulase positive?
what type of infections does it cause
NO!
nosocomial and opportunitic infections
Infects prosthetic devices and IV catheters
what is the only type of staph that is coagulase positive
staph aureus.
Does strep form catalase?
No it has a peroxidase system instead!
What are our beta hemolytic streptococci
S. pyogenes and S. agalactiae
What are the alpha hemolytic streptoccoci
S. pneumoniae and S. viridians
What diseases does S. Pyogenes cause
is it alpha or beta hemolytic
Group A or B
Group A beta-hemolytic strep
- pharyngitis
- cellulitis
- impetigo
- scarlet fever
- toxic shock like syndrome
- nectrotizing facitis
- rhematic fever
- acute glomerulonephrtits
What are the two main virulence factors of B-hemolytic S. pyogenes
- M protein: resists phagocytosis
- hylaronic acid capsule: reduces immune response
-Extracellular toxins:
Streptolysins
Pyrogenic toxins
Superantigen
What are the 3 squellae of strep pyogenes
- scarlet fever
- rheumatic fever
- acute glomerulonephritis
Streptococcus agalactiae
Group A/b?
Beta/alpha hemolytic?
where does it infect you
Group B beta hemolytic strep
Resides in the vagina and ins transfered to infant during delivery
Neonatal pneumonia, sepsis, meningitis
Strep viridans
Beta or alpha hemolytic
what disease does it cause
what is its main virulence factor
Alpha hemolytic
Causes dental caries and subacute endocarditis
Optochin resistant
What shape is strep pnuemonia
what diseases does it cause
Lancet-shapped
pneumonia
meningitis
otitis media in kids
sinusitis
What are the main virulance factors for S. pneumoniae
Large capsule
Alpha hemolytic
optochin sensitive
What culture requies blood or chocolate agar to grow
S. pneumoniae
What is our group D organisms
are they sensitive or resistant to optochin
Enterococci and Strep. Bovis
Optochin resistant
what disease do enteroccus cause
opportunistic urinary, biliary and subacute endocarditis
What disease do streptococcus bovis cause
cancer in the colon bovis in the blood
What grows on sheep blood agar
S. aureus
What are the two classes of gm+ bacilli
list them
Spore Formers and Non-spore formers
- bacillus
- clostridium
- listeria
- cornybacterium
What are the aerobic spore forming gm+ bacilli
Bacillus
- B. cerus
- B. anthracis
What are the anaerobic spore forming gm+ bacilli
Clostridum
- C. Botulinum
- C. tetani
- C. perfringenes
- C. diff
What are the non spore formers
Listeria and Cornybacterium
-L. monocytogenes
C. diptheriae
What is the microscopic and colonial morphology of B. anthracis
- Bamboo appearance due to gm+ rods with square ends
- Medusa head or beaten egg head
What grows on blood agar
B. anthracis
What are the main virulence factors of B. anthracis
- polypeptide capsule
- potent exotoxin
What do you find when someone gets anthrax
Black, necrotic eschar
woolsorter’s disase (pulmonary anthrax)
Main factors of B. cereus
motile
no capsule
saprophyte
Which is penicillin resistent
B. anthracis or B. cerus
B. cereus
How does tetanospasmidin work
via the tetanus toxin which binds to ganglioside receptors and blocks release of inhibitory mediators (GABA) at soinal synapses leading to hyper reflection and spastic paralysis
What bacteria causes spastic paralysis
Tetanospasmidin
what bacteria causes lock jaw(trismus)
teanospasmidin
this is known as risus sardonicus
what is the pathogenesis of botulism
neurotoxins enter and bind to peripheral cholinergic nerve endings
- inhibits release of acetylcholine
- symmetrical descending paralysis occus beginning with cranial nerves and progressing downward
What causes descending paralysis
Botulism
What diesease does C. perfringens cause
How is it identified
gas gangrene and food poisoning
-Nagler Reactions
What toxins does C. perfringens create
- alpha toxin: (lecithinase)lyses RBC and causes tissue destruction
- beta toxin
- enterotoxin
C. diptheria
Gram positive bacilli that causes diptheria and is an opportunistic nfection
Is c. diptheria capsulated, is it motile
no no
sx of diptheria
fibrinous excudate (pseudomembrane), nasopharyngitis, enlargement of neck lymph nodes and neck edema. Irregularity of cardiac rhythm
Who is commonly affected by listeria
how
Pregnant moms , newborn, weak immune system from unpasturized milk, cheese and deli meats
What is catalase and oxidase positive
listeria
What does listeria cause
meningitis and sepsis
MC cause of neonatal minigitis
What bacteria has a lipid rich cell wall and is acid fast
Mycobacteirum
what bacteira casues a ghon complex
mycobacterim
What bug causes hansens disease
Mycobacterium leprae
What does leprosy do
entry through blood vessels
inflammatory response
demyelination
What are the two types of leprosy and what type of TH response do they create
Tuberculoid:
TH-1 response producing interferony gamma
Lepromatous leprosy:
T cell failure and macrophage dysfunction and problems with interferon gamma
TH2 ctokins and humoral response
what are gram negative short rods that cause meningitis
H. influenze
