Vasculitis Flashcards
define vasculitis
a heterogenous group of rare inflammatory conditions that can occur independently or as a complication of an established disease (eg. RA or SLE)
basic pathophysiology
sterile inflammation directed against a blood vessel wall, leading to damage and destruction to the vessel wall (histologically seen as fibrinoid necrosis)
distribution of vasculitis
may localise to a single organ/vascular bed (relatively benign)
more commonly generalised and causing organ failure - combination of ischaemia (vessel obstruction) and bleeding (aneurysm formation)
clinical distinction of different types of vasculitis is mainly based on
assumed vessel size affected based on pattern of organ injury
types of large vessel vasculitis
takayasu arteritis
giant cell arteritis
medium vessel vasculitis
polyarteritis nodosa
Kawasaki disease
ANCA-associated small vessel vasculitis
microscopic polyangitis
granulomatosis with polyangitis (Wegener)
eosinophilic granulomatosis with polyangitis (churg-strauss)
immune complex small-vessel vasculitis
cryoglobulinaemic vasculitis
IgA vasculitis (hence-schonlein)
hypocomplementemic urticarial vasculitis (anti-C1q vasculitis)
where might you find a continuous vascular tissue bed
has tight junctions
found in CNS, lymph nodes, muscle
what’s continuous vascular tissue beds used for
has tight junctions
used for BBB, lymphocyte homing, metabolic exchange
where might you find a fenestrated vascular tissue bed
has fenestra
found in exocrine glands, GI tract, choroid plexus, kidney glomeruli
what’s fenestrated vascular tissue used for
has fenestra
secretion
absorption
secretion
filtration
where might you find discontinuous vascular tissue
has gaps
liver, bone marrow, spleen
what’s the purpose of discontinuous vascular tissue
has gaps
particle exchange, haematopoiesis, blood cell transfer
what are pericytes
cells interacting with blood vessels in brain parenchyma
help to
- contribute to BBB
- immune and phagocyte functions
- role in haemostasis
- contracitile functions
- participate in vascular development
what increases the vulnerability of vessel walls to inflammation
exogenous (infections/toxic)
endogenous (ageing)
typical symptoms of vasculitis
regardless of size of vessels involved, patients often present with:
fever, night sweats, fatigue, anorexia, weight loss, arthralgiaa
some life or organ threatening manifestations of vasculitis
alveolar damage
rapidly progressive glomerulonephritis
mesenteric ischaaemia
orbital pseudotumour threatening optic nerve (in GPA)
vision loss in patients with giant cell arteritis
lab diagnostics for vasculitis
hb, ESR, CRP, serum albumin, creatinine, urine MCS/ACR
antineutrophil cytoplasmic antibodies (ANCA) tests
inducing remission
high dose corticosteroids (often combined with cytotoxic immunosuppressants for severe disease), usually for 3-6 months
gold standaard for ANCA associated vasculitis
rituximab (anti-CD20, B cell depleting agent)
aims during period post remission
during this period, goal is to eliminate corticosteroids or reduce their dose and to use less potent immunosuppressants eg. methotrexate, azathioprine
maintaining remission
corticosteroids tapered to zero or lowest dose that maintains remission
usually methotrexate with folate or azathioprine is prescribed to replace cyclophosphamide
if patients have frequent relapses
they may need to take immunosuppressants indefinitely
