Mar26 M2-Infection and immunity Flashcards
things that influence the symptoms of a disease with inflammation
- immune system impaired
- infant (not same symptoms as adults)
- being on a statin
biologic drugs used in many diseases: what they do
immune system modifiers
statins effect on the immune system
- compromise the immune system
- compromise macrophages (supposed to cause plaque rupture). ats not stopped but plaque rupture stopped
fever, malaise, was in quinolone resistant malaria strain area when travelled in Africa = number 1 on ddx
acute viral illness infection (malaria is only number 2)
concept of route of infection in the body
- diff routes of entry of pathogens (airways, GIT, reproductive tract, external surface, wounds, insect bites)
- each route has its pathogens
important pathogens in airway, GIT and reproductive tract routes
airways = influenza
GIT = salmonella, rotavirus
reproductive tract = HIV, treponema pallidum
4 classes of pathogens
- EC bacteria, parasites, fungi
- IC bacteria, parasites
- viruses (IC)
- parasitic worms (EC)
1st symptom of malaria
periodic fever
malaria type of infection
intracellular parasitic infection (enters and lives in RBCs)
immunologicla charact of RBCs
no MHC 1, malaria invisible to immune system in RBC. when RBC full, bursts, malaria goes in other RBCs
how microbes get through epithelial barriers of the body
- mechanical effects (cuts, breaks, bites)
- chemical (they can secrete stuff to compromise our barrier)
- compromised gut flora (serves as protection normally)
factors that influence the incubation period of a virus (3)
- amount of inoculum you got (how much virus)
- virulence of the infection (how many substances released and that serve as stimulus)
- immune system reaction
3 steps of immune response after infection (3 time categories)
- innate immunology (0-4 hours) = non specific receptors
- early induced response (4-96 hours) = PAMPs
- adaptive immune response (clonal expansion of B and T cells)
when does adaptive immune system act in infection and how long before you see an Ab
- doesn’t act until at least 4 days
- see first Ab after 2 weeks
there’s a certain level of Ag needed for the adaptive immune response to be involved: name of that concept
antigenic window (is a threshold) (at threshold, end of incubation period)
def of incubation period
time to onset of symptoms = time to threshold (of adaptive immunity)
(imp) 5 acute phase cytokines + def of that
- cytokines released first and that cause the first blush of symptoms
- IL-1, IL-6, IL-8 (CXCL8), IL-12, TNF-alpha
why route of infection is key in immunity
- will try to localize infection to its original site
- systemic dissemination and infection that spreads = LOT of inflam + HARD to target (bc cytokines released everywhere by macrophages = confusing for neutrophils)
what helps localize an infection to its original site
antibodies
liver role in inflammation
produces acute phase reactants
- platelets
- CRP (acts as an opsonin on bacteria + activates the complement). important for abcesses bc they can hide
abscess management and prognosis if watch and wait
management = drain, give Abx, until microbes gone
watch and wait = abscess will win and spread
3 things that can happen if you stop Abx (for an abscess for ex) too soon (the 3 Rs)
- reappearance of the abscess
- resistance (if new microbe grows again)
- regrowth
how to follow an abscess and know when it’s gone
watch CRP and follow until back to normal
CRP still elevated after normal Abx time 2 things to do
- rethink dx
2. continue Abx
