immunology Flashcards
discuss vasculitis what is it, how is it classified and examples of each
inflammatory disorders of blood vessels.
classified using chapel hill criteria.
- affects any organ and presentation can depend on the organ affected.
Large- giant cell arteritis, Takayasu’s arteritis
Medium- Polyarteritis nodose, kawasaki disease
Small- goodpasure, immune complex vasculitis (there’s lots of these)
Variable- bechets and cogans.
discuss systemic symptoms of vasculitis + generalised tests that can be done
Overwhelming fatigue
inc ESR, CRP- consider in any unidentified multisystem disorder.
Tests:
CBC- ESR/CRP, ANCA +ve.
Urine: proteinurea, haematurea, casts on microscopy, angio +/- biopsy.
discuss giant cell arteritis/ temporal arteritis
common in the elderly- consider takayasus if under 55.
strongly associated with PMR, large artery.
S+S: headache, scalp tenderness, temporal artery tenderness, tongue/ jaw claudication, sudden unilateral blindness.
Ix: ESR + CRP, plts inc, ALP inc, dec Hb, Temporal artery biopsy,
Rx: pred 60mg orally Or if concern for vision loss IV methylpred.
typically 2 year course, then wean off, complication is vision loss. though death due to steroid use is the main cause of morbidity.
discuss polyarteritis nodosa
PAN
necrotising vasculitis - causes aneurisms and thrombosis in medium sized arteries. - infarcts the associated organ + severe systemic symptoms.
male:female 2:1
associated with hep B.
renal issues are the main cause of death.
Ix: inc wcc, anaemia, ese, crp, anca positive, renal/mesenteric angiography often shows disease signs.
Rx:
control BP, steroids for mild causes, steroid-sparing agents if more severe (methotrexate/ other dmards)
discuss microscopic polyangiitis
a necrotising vasculitis affecting small + med small- kidneys and lungs mainly.
usually presents with rapidly progressive glomerulonephritis, pulmonary haemorrhage (30%)
Ix: panca +ve.
Rx:
steroids + methotrexate
what is primary and 2’ immune deficicy
primary- something that results from a genetic heterogeneous group of disorders that result from defects in immune system development and/or function.
secondary- when the immune system is compromised from a external factor- e.g HIV, chaemo, burns, dehydration.
treatment of primary immune disorders
1 in 1200 live births in the us
classified according to the part of the immune system they disrupt.
will present with recurrent or unusually severe infections (sinusitis, ottitis, pneumonias, skin)
Ix: will be through blod analysis (electrophoresis, differentials)
Rx:
aggressive management of current infection + treatment of specific cause of immuno deficiency.
consider bone marrow/ stem cell replacement for permanent
some quick points about antimocrobial stewardship
in hopsital should have cultures before prescription / utilisation of abx
consider if essential- for the individual if resistance occured, and for society.
define hospital aquired infection, risk factors and incidence.
an infection that is not present or incubating priod to infection.
generally 48 hours after admission to hospital.
risk factors: immunosuppression, older age, length of stay, multiple underlying comorbidities, frequent visits, mechanical ventilatory support, recent invasive procedures, indwelling devices, and stay in an intensive care unit (ICU).
4% of patients get one HAC.
most common organisms causing HAI
C diff, staph aureus, klebsiella
pneumonia, surgical site, Gi, UTI.
for catheter assoc- 7 day Abx.
HAP- 7days abx
vanc for C diff.
