Infection Corrections Flashcards
What is the most common fungal infection? How would you test for this infection?
Aspergillus
PCR for Aspergillus
Or test for cell wall components
Beta glucan
Galactomannan
which endotoxin is commonly seen in the wall of gram negative bacteria?
Lipopolysaccharide
how can microorganism enter a non-phagocytic cell?
zipper method - trick cell into forming cell junction with microorganism
trigger method - bacteria injects things into the cell so the cell moulds around it.
for some viral infections there is no treatment and the host must fend of the infection themselves.
what must occur to initiate an effective host response?
cells form a viral peptide-MHC class 1 complex which is presented on the surface of the cell
how does staphylococcus epidermidis cause infection?
produces an extracellular polysaccharide slime that facilitates adherence to prosthetic material surfaces e.g. catheters or central lines
the slime becomes part of an expanding biofilm which can be difficult to eradicate
which antibiotic is used to treat staph aureus?
beta lactams (e.g. fluclox) or glycopeptides (vancomycin)
both act as cell wall synthesis inhibitors
what allows clostrodium (c.difficile) to survive outside of host for long periods?
form spores
spores are the most resiliant life form known - they can survive boiling, UV light ad bactericidal chemical agents
which antibiotic is used to treat C.difficile?
oral metronidazole (or oral vancomyocin):
* these are used against anaerboic bacteria and protozoa
how does HIV bind to lymphocytes?
gp120 docking glycoprotein binds to CD4 receptors
It is extremely important to avoid alcohol while taking which antibiotics?
metronidazole since it inhibits aldehyde dehydrogenase resulting in accumulation of acetaldehyde
what disease does helicobacter pylori cause?
main cause of gastric and duodenal ulcers + can result in gastric cancer
since it is able to survive a highly acidic environment
what investigation must be completed before antibiotics are aministered for sepsis?
blood culture
how does normal flora prevent the growth of candida albicans in the vagina?
normal flora which is the lactobacillus species produces lactic acid
what is the function of CRP?
promotes opsonin mediated phagocytosis
which nisseria meningitidis virulence factor is part of the vaccine that protects some but not all serogroups of nisseria meningitidis?
capsule - protects against phagocytosis
the capsule varies amongst different serogroups
which antibiotic is used to treat nisseira meningitidis?
ceftriaxone
what kind of swab is used to detect presence of nisseria meningitidis?
throat swab
which immune components are activated in a viral infection?
virus infection stimulates TH1 response which activates CD8 T cells and stimulate their differentiation and expnsion into cytotoxic T lymphocyte
the THC 1 response also regulates the production of antibodies against the virus