Skin wounds Flashcards
What gram positive cocci cause skin & tissue illnesses?
Staphylococcus aureus Staphylococcus epidermis Streptococcus pyogenes, group A Viridans Strep Enterococcus Faecalis
Which bacteria that causes skin and wound infections that is Gram positive cocci in clusters?
Staphylococcus aureus
Staphylococcus epidermis
Which gram positive cocci in cluster bacteria is more likely to cause a skin infection and is organized in large Yellow Beta hemolytic colonies?
Staphylococcus aureus
What bacteria is gram positive cocci in chains?
Streptococcus pyogenes, group A
Viridans Strep
Enterococcus Faecalis
Which gram positive in chains bacteria can be alpha hemolytic or non-hemolytic?
Viridans Strep
of the gram positive in cocci in chains is also beta hemolytic?
Streptococcus pyogenes, group A
What Gram positive Bacilli causes tissue necrosis and what are its other morphological characteristics?
Clostridium Perfringens
it is also anaerobic & spore forming
What are the gram negative Bacilli that can cause skin and tissue illnesses?
Vibrio Vulnificus E. Coli Proteus spp Providencia spp. Aermonas spp. Plesiomonas shigelloides Pseudomonas aeruginosa Acinetobacter baumannii Bacteroides Fragilis
What are the 2 different Gram positive Bacilli that cause skin/tissue infections & what differentiates them?
Clostridium Perfringens- anaerobic
Bacillus Antracis- aerobic
What is known for causing Impetigo, Folliculitis, Furuncles. & Abscess
Staphylococcus aureus
Staphylococcus aureus is also known for cuasing Scaled skin syndrome, which is also known as Toxic Epidermal Necrolysis (TEN) in childern under 5 what is this disease process characterized by?
initially localized red rash following conjunctivitis or URI; then Large Flaccid Bullae rupture & sheets of epidermis peel/reveal moist, red, scaled dermis
A female patient presents with an acute illness accompanied by a high fever, diffuse rash, hypotension.. Upon physical exam it is noted that patient has been using absorbent tampons, what is the possible disease process & the causing bacterial agent?
Toxic shock syndrome-
due to Toxic shock syndrome Toxin (TSST) of Staphylococcus aureus
a patient presents with Superficial skin infection characterized by small “blisters”/pustules followed by thin crust over area, which is also been accompanied by a scarlett fever, what bacterial agent & virulence factor are causing this illness?
Streptococcus pyogenes, group A
erythrogenic toxin
what are the virulence factors of Staphylococcus aureus?
- Coagulase, fibrinolysin, lipase, & various proteases
- Adhesive matrix (biofilm)
- Quorum-sensing
- (many have) superantigens
- pathogenicity largely due to Plasmids
- (85% produce) beta-lactamase resistant to most penicillin’s / cephalosporins
- (30% MRSA) Methicillin Resistant to all beta-lactam antibiotics
What 2 bacteria cause 90% of all skin infections?
Staphylococcus aureus
Streptococcus pyogenes, group A
A patient present with a large diffuse red rash, that is warm to the touch and the area is swallon. What skin infection is this likely, and what bacteria may be causing/ what virulence factor should be tested to differentiate it?
Cellulitis
Staphylococcus aureus
Streptococcus pyogenes, group A
Coagulase- Group A Strep doesn’t produce and cellulitis is the halmark of Group A strep.
This is characterized by the rapid destruction of muscle & fat tissue /high fever & pain is considered invasive & life threatening? what causes it & treatment?
Streptococcal Toxic Shock Syndrome/Necrotizing Fascitis/ strep gangrene, invasive cellulitis/ “flesh eating bacteria”
Group A Strep
Tx: agressive antimicrobic & surgical intervention
What are the virulence factors of Streptococcal pyogenes, group A?
’s envasive enzymes & toxins
Hyloronic capsule-appears as “self” Ag to host slows Ab response
“M” Protein, antiphagocystic
Erythrogenic toxin causes scarlet fever rash
Streptolysin O&S—cytotoxic; & base for ASO titer
A Patient developed an abcess after a traumatic accident in Afghanistan, if this particularbacteria is expected it will grow on McConkey media?
Acinetobacter baumannii
Apatient presents with an skin infection after visiting an area w/ warm costal sea water. Upon the infection had hemorrhagic bullae & necrotizing fasciitis. what bacterial agent is suspected & what is it morphological presentation?
Vibrio Vulnificus
GN Bacillus, curved
