Infectious Disease 1 Flashcards
colonization v invasions
colonization- bacteria is associated w/ humans but havent broken thru barriers
invasion- breaks thru barriers and cause disease
opportunistic infections
only occur when there is a defect in the host
acute bacterial pneumonia
streptococcus pneumonia
encapsulated, gram positive
capsule prevents phagocytosis. prevents IgA. cell wall causes inflammation (TNF-a/ IL-1)
colonization leads to bacteremia using laminin and platlet activating factor receptors
recruits PNMs
pathological stages of bacterial pneumonia
1 edema- serous exudate- pink fluid
2 acute inflammation- PMNs, activation of complement and coagulation cascades. causes fibrin polymerization
3 consolidation- hepatization. fibrin and inflammatory cells form a firm mass w/in the air spaces of the lung
4 resolution- macrophage clean up of inflammation. in streptococcus pneumonia, the archetecture is preserved.
endocarditis
infection of heart valve
can be acute (rapidly progressive) or subacute (slowly progressive)
subacute- caused by streptococci (viridans strep)
acute- caused by staphylococcus aureus
acute bacterial endocarditis
staphylococcus aureus- pyogenic gram positive. seed onto fibrin deposits
virulence factors encoded on pathogenecity islands
leads to destruction of valve surface. aortic and mitral most common. erodes into valve ring and prevents it from closing
systemic effects- emboli can travel anywhere- including superficial vasculature of skin
types of vegetions
rheumatic
infectious
non bacterial
auto immune
acute bacterial endocarditis is infectious
pyelonephritis
bacterial infection of kidney- usually enteric gram negatives
associated w/ UTI or anatomic abnormalities
can become chronic
what organism is most commonly associated w/ ascending pyelonephritis
e coli- facultative gram negative bacilius
causes inflammation in interstitium and renal tubules
complications: papillary necrosis, pyonephrosis, and perinephric abcess
