ID2 Flashcards
salmonella typhi is
intracellular gram negative enteric bacillus
salmonella reservoirs, but salmonella typhi
most animals have reservoirs, but salmonella typhi is an exclusive human host
how does typhoid fever get into GI tract?
fecal contaimination fo water, food (human reservoir)
how does TF attack?
invades monocyte-macrophage cells–>produces endotoxin
what is typhoid fever?
infection of small bowel lymphatics with bacteremia
ulceration, bleeding, and perforation
disseminated infection: osteomyelitis (infection of bone)
chemokines from salmonella typhoid
do not direct neutrophil migration
where is inflammation in TF?
peyer’s patches
spleen
liver
3 phases ST?
infection
dissemination
pathologic lesions
sign of TF
red spots on abdomen
hemorrhagic lesions on ileum
mnonuclear cells with intracellular bacteria in liver
mononuclear cells and red blood cells in stool
mycobacterium tuberculosis
acid fast, aerobic intracellular bacterium with waxy cell wall
path of tuberculosis
taken up by macrophages and multiples within non-acidified phagosomes
–>delayed-type hypersensitivity: CD4 cells stimulate TNFa & IFNg secretion–>macrophage activation–>epitheloid granuloma formation
CD8 cells can lyse macrophages
glycolupid factors
induce granulomas
lipoarabinomanan
similar to LPS
inhibit macrophage activation
path to tissue destruction and hemorrhage
granulomatous inflammtion, caseation necrosis, liquefaction
**balance of cytoknes is the key
balance of TNF
human allelic variants of Leukotriene hydrolase control
too little–>uncontrolled growth
too much–>tissue destruction
**can lead to immuity by activated macrophages
marker of Tb
lung granuloma with multinucleated giant cell
type of chronic inflammation and scarring
lung abscess and empyema
lung absecess and empyema
mixed aerobic and anerobic bacteria–>associated with aspirated upper resp flora
–>tissue destrctuion–>walled off fibrous cavity and liquefied central cavity–>mac, lymph and plasma cells surround areas by continuing bacterial growth–>resolution by drainage through bronchus or chest wall–>scarring and restriction of lung capacity
greater than 90% tb
healing, calcification ,formant–>can reactivate or reinfection–>then get secondary cavitary tb
less than 10% tb
progressive primary Tb
greater suceptibility of progressive primary tb in
certain racial groups
children
immunosuppressed hosts
