ID/Immuno Flashcards
what is one of the most important cytokines in sepsis? list some other imp cytokines
TNF-alpha
IL1, IL6
IL3 produced by ___.
-function?
activated T cells
stim growth and differentiation of stem cells in bone marrow
IL4 made by ___.
-function?
TH2 T-helper cells
stimulates growth of B cells and increases number of TH2 T-helper cells at site of inflammation
IL10 made by ___. function?
antiinflamm cytokine made by macrophages and TH2 T-helper cells
limits the production of proinflamm cytokines (eg interferon gamma, IL2, IL3, TNFa)
function of leukotriene B4
stimulate neutrophil migration to site of inflammation
transforming growth factor-beta made by __.
-function?
released by macrophages
anti-inflamm roles in sepsis incl suppressing release of IL1 and TNFa, and inhibiting lymphocyte proliferation
deficiency of ___ results in recurrent Neisseria infections
MAC attack complex (C5b-C9)
Terminal complement deficiency- any of C5-C9
prophylaxis for Mycobacterium avium complex infections
azithromycin
for AIDS pts CD4 <50
describe the process by which neutrophils go from bloodstream to site of inflammation
rolling
crawling
azole MOA
inhibit synthesis of ergosterol by fungal cytochrome p450
they also suppress human P450 system = many drug interactions (increae levels of drugs metabolize by liver P450- eg warfarin, cyclosporine, tacrolimus, oral hypoglycemiscs)
what is the most common cause of hydatid cysts?
what can happen when cyst spills?
where do most cases occur?
echinococcus granulosus
spill can => anaphylactic shock (perform surgery with caution)
endemic areas (eh easter Meditt, middle east, south am, subsaharan africa, former soviet union, western china) OR ppl in SW US with sheep or dogs
unilocular hydatid cysts seen in what infection?
multilocular?
unilocular- E granulosus
multi- E. mulilocularus
purpose of adding clavulanic acid to amoxicillin?
is a beta-lactamase inhibitor ->decrease amoxicillin cleavage by bacterial cells
-some bact make beta-lactamase which hydrolyzes the beta-lactam ring of penicllin family
adding beta lactamase inhibitor expands amoxicillin’s spectrum of activity to include strains of beta-lactamase syntheszing bacteria that are resistant to amoxicillin alone
HLA-B*57:01 allele associated with what
Abacavir hypersensitivity
(a nucleoside reverse transcriptase ihibitor NRTI used to treat HIV/AIDS)
abacavir directly binds to a segment on the HLAB*57:01 molecule, altering presentation of slef-peptides to immune system resulting in a delayed hypersens reaction (type IV)
most common bacterial cause of acute parotitis
what are risk factors for suppurative parotitis
how diagnosed
staph aureus
risk factors = decreased salivary flow
- meds (eg anticholinergics)
- obstruction (eg calculi, neoplasm)
- dehydration, postsurg/intubation)
duagbosis = elevated amylase without elevated lipase
malaria is caused by what species?
what does it look like on blood smear
Plasmodium (there are four species)
trophozoites w/ diamond ring appearance in RBC
describe life cycle of parasite transmission
transmitted by female Anopheles mosquito during blood feed
goes to liver to infect hepatocytes
undergoes asexual repr which makes hepatic schizonts with thousands ot daugther cells (merozoites)
rupture of schizont into circulatory system–> erythrocyte infection and cycles of intraerythrocytic reproduction
paranasal sinus complaints
DM/immunosuppression
non septate hyphae branching at right angles
this is most likely?
mucormycosis
an opportunistic infection caused by rhizopups, mucor, and absidia species
what binding interactions are needed in activation of B cells?
MHCII (B) binds T-cell receptor
CD40(B) binds CD40-ligand on T cell
B7 (B) binds CD28 (T)
when do maternal Ab fade
after 6 months
Wiskott-Aldrich syndrome
- cause
- inheritance, mutation
- symptoms
- treatment
X-linked recessive
mutation in WASp gene imp for cytoskeleton rearrangement -> defective antigen presentation
is a combined B and T cell disorder
Wiskott Aldrich Thrombocytopenia Eczema Recurrent infections
infections worsen as patient ages, apparent after maternal IgG and mucosal IgA from breast milk are degraded at 6months
HLA-matched bone marrow transplant
Chediak-Higashi syndrome
- gemetics
- cause
- signs/symptoms
defective lysosomal trafficking regulator gene (LYST)
microtubule dysfunction in phagosome-lysosome fusion
AR
Progressive neurodegen Lymphohistocytosis Albinism Infections Neuropathy
list 5 chemotactic agents that stimulate neutrophil migration to site of inflammatoin
IL-8 n-formylated peptides leukotriene B4 5-HETE (the leukotrient precursors) C5a
erythroblastosis fetalis and hemolytic disease of the newborn do not occur in what blood type(s) / do occur in what blood type(s)?
why?
does NOT occur in maternal blood types A and B as the anti-A and anto-B Ab are IgM type and can’t cross the placenta
occurs in type O mothers as antibodies are predominantly IgG and can cross placenta to case fetal hemolysis
SCID
- what two inheritance patterns/causes
- signs and symptoms
- treatment
XLR defective IL-2R gamma chain
AR adenosine deaminase deficiency
- present in infancy w/ recurrent bacterial, viral, fungal, and opportunistic infections
- failure to thrive
- chronic diarrhea
decr T-cell receptor excision circles (TRECs), absent thymic shadown, germinal centers, and T cells
bone marrow treatment
chronic granulomatous disease
- cause
- lab signs
NADPH oxidase defect (can’t make superoxide, hydrogen peroxide for resp burst)
X-linked most common
incr susceptibility to catalase+
nitroblue tetrazolium die reduction test fails to turn blue
what cytokin stimulates antibody isotype switching
IL-4
esp swtiching to IgE
thymus and ___ develop from ___ pharyngeal pouch
inferior parathyroid
3rd
what is rheumatoid factor
IgM antibody specific for the Fc component of IgG
infiltrating CD4 cell secrete cytokines that stim B cells to make rhyematoid factor and anti-CCP antodies –> RA
pubic louse
-treatment MOA
topical permethrin cream blocks parasite’s sodium ion conduction in nerve cell channels –> paralysis and death
most common cause of hematogenous osteomyelitis
staph aureus
is predom a disease of children, freq affects long bones
strep pyogens (group a strep) is second most common cause
widespread epidermal sloughing, esp with gentle pressure
- what is this caused by and MOA
- what is this sign called
staphylococcal scalded skin syndrome–due to production of the extoxin exfoliatin
blistering only in the superficial epidermis. the toxins act as proteases and cleave desmoglein in desmosomes
Nikolsky’s sign
what can trigger IgE INdependent mast cell degranulation?
does so by activation of PKA and PI3 kinase
medications including
- opioids
- radiocontrast agents
- some antibiotics eg vancomycin
diffuse itching and pain, bronchospasm, localized swelling
what can cause IgE-DEpendent degranulation
usu a/w environmental exposures like foods or stings
or meds like beta-lactam and sulfonamide abxs
Terbinafine
- moa
- usage
treat dermatophytosis (ringworm)
inhibits fungal membrane ergosterol by suppressing the enzyme squalen epoxidase
caspofungin moa
blocks beta(1,3)-D-glucan which is a main component of Candida and Aspergillus cell walls
Griseofulvin moa and use
binds polymerized microtubules and disrupts fungal mitotic spindle
accumulates in the skin, only effective for dermatophytosis
what does IL-12 do
triggers differentiation of T-cells to Th1 cells
Nystatin
- moa
- usage
polyene antifungal
binds ergosterol in fungal cell membrane, causing formation of pores and leakage of fungal cell contents
is not absorbed from GI tract and is given as an oral swish and swallow agent
DOC for oral candidiasis in pts without advanced immundeficiecny
cause of hereditary angioedema
what drug should NOT be given to them
low C1 esterase inhibitor, which normally suppresses activation of C1 complement (this rest of cascade) and inactivates kallikrein which converts kinongen to bradykinin
= increase bradykinin
bradykinin, C3a, and C5a mediate angioedema by increasing vasodilation and vascular permeability
what are the two most imp opsonins
IgG
C3b
which can also bind C3b convertase and form C5 convertase, ult triggering MAC
what are the two mos common causes of SCID
X-linked
Adenosine deamine deficiency (AR) –> adenosine accumulation is toxic to lymphocytes
what interferons do most human cells make in response to viral infection? what do they do?
interferons alpha and beta
help suppress viral refplic by halting protein synth and promoting apoptosis of infected cells –> limits virus ability to spread
cause of green sputum / pus in bact infections
myeloperoxidase, which is a blue-green heme-based enzyme released from neutrophil azurophilic granules and makes hyypochlorous acid (Bleach)
best time and agent to give pregnant woman to protect baby against Group B strep
35-37 weeks gestation
first choice penicillin
name and explain a major virulence factor of M. tuberculosis
cord factor - a hydrophobic surface glycolipid
forms cylindrical micelles around M. tuberculosis to prevent macrophage destruction within the phagolysosome
forms toxic crystalline monolayer hydrophobic surface that drive formation of caseating granulomas
