Streptoccoci GAS Flashcards
Group A ______
streptoccoci pyrogenes
what does strep pyrogenes (SP) look like?
MRSA, white colonies with clear zones of Beta hemolysis. gram +
strep pyrogenes has a ______ antigen
carb
where does colonize? causes?
oropharynx, pharyngitis (not strep anigous)
catalase postive or negative?
negative
how does SP spread?
respiratory droplets and breaks in the skin
what time of year does SP occur most often?
colder months - pharyngitis rheum fever and glomerular nephritis —- warmer: skin dz
when you have a skin infection…
you assume is staph primarily bc both do skin. then do dx test.
S+S of strep throat? hard to differentiate from _____? how do you dx?
normal flu like symptoms and erythmatosis with exudate, palatal petichae. dx with serology or c+s. hard to differentiate from viral dz and mycoplasma
scarlet fever
complication of strep throat and pyro exotoxin.
S+S of scarlet fever
red face rash upper extremities and upper chest; strawberry tongue, yellowish stuff on tongue sheds off, peritonsillar or retropharyngeal abscess, OM, sinusitis
pyroderma impetigo
purulent infection of the skin, face UE LE, associated with strains that do not cz pharyngitis, skin breaks
when does SP start to use enzymes?
once it hits the facious layer or plain
eripselas
acute local painful skin infection. systematic and lymph. child fever and lymphocytosis
cellulitis
skin and deep, can only treat if know precise organism
necrotizing faceitis
strep more than staph. deep sq and fascia. skin break. 50% die. need to debride and abx
progression from cellulitis
bullae, gangrene, sepsis, mods, death
bacteremia - dx? babies?
in babies its gbs. but in gas you dx with a positive blood culture of beta hemolytic strep
strep toxic shock syndrome
highly associated with bacteremia and ned facitis - soft tissue infection with nonspecific ss of systemic infection. progresses to mods.
associated with M types
what toxin produces STSS?
SpeA or streptotoxigenic pyrotoxin A
rheumatic fever - SS? dx?
complication of SP pharyngitis. post strep - no more bacteria. have paricardtitis, sq and in vessels. sq nodules on heart and tissues. damage to valves. joint involvement, specific m type
dx: no specific test to dx so you rely on recent strep infection/hx. also GAS increases ASP or anti streptomycin O antibody
ASO
group A antigen increases anti streptomycin O antibody
acute glomerular nephritis - SS? dx?
last protein s/p inflammation. acute. nephrogenic strep strains, edema htn hematura and proteinura.
ASO titer
haluronic acid
capsule virulance. prevent phago via assembly of human ECM and prevent c3b from binding.
