Extra bacteria and topic information Flashcards
coagulase negative staphylococci and some characteristics
all normal skin flora
Staphylococcus hominis - opportunistic pathogen
S. hemolyticus - causes sepsis,endocarditis, Beta hemolytic
S. lugdunesis - endocarditis
Streptococcus genus characteristics
- either alpha or beta hemolytic
- lancefield carbohydrate antigen classification (not strep pneumo or viridans)
- all catalase negative!!
- most are faculative anerobes
oral streptococci and cariogenisis
- the viridans group - typically are alpha hemolytic strep that are resistant to optochin and bile insoluble
- this group is S. mutans, S. salivarius, S. sanguis, and S. mitis.
- caries are produced when S. mutans secretes dextran and levan to attach to the enamel, causing destruction of the enamel and dentin via the production of acid. if not stopped/removed, the invasive bacteria can enter the blood stream, causing endocarditis of heart valves.
- lactobascillus may or may not be involved
virulence factors and symptoms of strep pneumoniae
capsule hyaluroniase DNAse IgA protease pneumolysin - RBC lysis
symptoms MOPS Meningitis Otitis media Pneumonia Sinusitis
anaerobic gram negative a positive bacteria and some characteristics
gram neg - bacteroides, fusobacterium - normal flora of mouth, skin, GI. more commonly in formula fed infants.causes endogenous infections
gram positive - peptostreptococcus anaerobius- normal flora of mouth , skin, GI. these cause abscesses, cellulitis, PID, etc infections
salmonella genus and salmonellaosis
enterobacteriae family, over 2000 types but enteritidis and typhi are the most common. there are 1500 sereotypes of those alone.
salmonellaosis is from salmonella enteritidis mainly - causes gastroenteritis in otherwise healthy people and can become invasive and cause sepsis in young, old or immunocompromised.
providencia and morganella genus
they used to belong to the Proteus genus because they cause the same diseases. pretty much the same thing, treatment, etc
the salmonella typhi vaccine is what
a killed vaccine that causes active immunization
what are the species names of the shigella genus?
shigella sonnei, shigella dysenteriae, shigells boydii
shigella has a direct effect on the GI besides the invasion aspect
leads to microabsecces in the wall of the colon and necrosis, leading to pseudomemebrane formation
the yersinia genus has one strange enzyme activity, what is it?
lactose negative BUT ONPG positive because it has Beta-galactosidase activity
the buboes in Y. pestis is what?
- when the flea bites you, it regurgitates the bacteria into the wound from the flea’s GI.
- There the bacteria infect PMNs and multiply intracellularly and travel in the lymph to the lymph nodes.
- the lymph nodes become enlarged and develop hemorrhagic necrosis => buboes
how is Y. pestis spread? It also causes which scary symptoms?
spread human to human through respiratory droplets, vector to human via flea bites. hemorrhagic pneumonia and hemorrhagic meningitis
Campylobacter jejuni has what shape, physical characteristic? What does this characteristic imply
- it’s comma shaped with a single flagella -> invasive
- the invasiveness of it means that it multiplies in the small intestine (causing bloody diarrhea, cramps)
- invades the epithelium –> enters the blood –> causes sepsis, endocarditis, meningitis
campylobacter jejuni causes what nervous system problem?
guillain-barre syndrome –> autoimmune process that causes ascending demyelination and paralysis
H pylori and campylobacter are grown on which media and pos for which tests?
- oxidase and catalase positive
- Skirrows media because they are microaerophilic that need 5% oxygen and 10% co2
- H. pylori is also urease pos (obviously)
vibrio cholerae enterotoxin does what?
- It is an AB toxin that activates the Gs protein that thus activates adenylate cyclase to increase cAMP
- the inc cAMP inhibits the Na pumps, leading to salt and water hypersecretion
- leads to dehydration, watery diarrhea, acidosis and shock
- treat with rehydration therapy, 1 tsp NaCl and 4 tsp glucose
what is another vibrio species to know?
vibrio parahaemolyticus - from seafood, causes mild cholera symptoms
aeromonas (name on topic list)
- gram negative facultative anaerobe rod
- bloody diarrhea, wound infections
- treat with ciprofloxacin
plesiomonas (name on topic list)
- motile gram neg, oxidase pos
- also seafood
- also diarrhea
Stenotrophomonas (name on topic list)
- is a random bacteria that is similar to pseudomonas in pathological symptoms, most commonly as a nosocomial infection with immunocompromised pts
- Oxidase NEG!
- pneumonia, urinary tract infection, or bloodstream infection
- in immunocompromised patients, cystic fibrosis- latent pulmonary infections
burkholderia (name on topic list)
important pathogen of pulmonary infections in people with cystic fibrosis (CF)