Immunology Flashcards
What cells are involved in chronic inflammation
T lymphocytes which secrete cytokines
plasma cells which produce immunoglobulin
neutrophils
eosinophils (parasites)
fibroblasts
macrophages (microglia in the brain)
characterised by large numbers of macrophages and granulation tissue
what cells are involved in acute inflammation
neutrophils (diagnostic)
what organism causes syphilis
treponema pallidum
what are the symptoms of syphilis
genital chancre
secondary rash
gumma (granuloma in tertiary disease)
what organism causes leprosy
mycobacterium leprae
what is the epidemiology of RA
more common in women
common between 30-50 years old
environmental factors may precipitate onset
describe some of the features of a rheumatoid joint
thinning of cartilage erosion of the bone inflamed synovium inflamed tendon sheath effusions synovial thickenings
what are the symptoms of RA
inflamed joints that are warm, tender, swollen, red, painful and difficult to move
fatigue
loss of apetite, weight loss, flu like symptoms, depression, anaemia
vasculitis
sjogren’s syndrome
heart and lung inflammation
what joints are affected in RA
foot ankle and knee hip (later on) hands and wrists almost always affects elbow (loss of motion) shoulders and neck stiffness
what organs are affected in RA
blood (anaemia) nerves (mononeuritis multiplex) heart (pericardial effusion) lungs (interstitial lung disease) eyes skin (rheumatoid nodules)
what type of anaemia is almost always present in RA
hypochromatic microcytic anaemia with low serum ferritin and low or normal iron binding capacity
how are the nerves affected in RA
vasculitis causes mononeuritis multiplex
peripheral nerve entrapment
cervical spine instability
how are the eyes affected in RA
keratoconjuntivitis sicca, (dryness of the conjunctivae and cornea) episcleritis, scleritis
what is major histocompatibility complex
Membrane glycoproteins that display peptide antigens to T cells
MHC 2 bind peptides derived from proteins from extracellular sources that have been internalised
presents peptides to CD4 t helper cells
what is the function of th1 cytokines
cell mediated immunity
what is the function of Th2
antibody responses
what genes are associated with RA
specific human leukocyte antigen (HLA)
HLA-DR4
involved in antigen presentation
higher risk of severity of homozygous
binds to arthritogenic peptides
target for autoreactive T cells
what is autoimmunity
immune mediated destruction of self tissues
occurs via specific recognition of self antigens
activation of self reactive lymphocytes by self antigens
what is tolerance
the process that keeps the immune system from attacking itself
thymic deletion of autoreactive cells and T regulatory cells
what are cytokines
proteins made by cells that affect the behaviour of other cells (e.g. interleukins)
what are chemokines
chemotactic cytokines
how is RA diagnosed
no definitive test
medical history
physical examination
lab tets -imaging, ESR, CRP
rheumatoid factor
what are the aims of RA treatment
relieve pain
reduce inflammation
stop or slow joint damage
improve functioning and sense of wellbeing
what medications are available for RA
NSAIDS
analgesics
corticosteroids
disease modifying: methotrexate sulfasalazine azathioprine cyclosporine hydroxychloroquine minocycline
infliximab (anti TNF)
rituximab
what is ankylosing spondylitis
chronic inflammatory arthritis affecting the spine
more common in males
association with human class 1 MHC molecule HLA b27
bone grows out of both sides of the vertebrae and may join them together
how is AS treated
NSAIDs, indomethacin, COX-2 inhibitors
anti TNF (infliximab)
what is HLA-b27 linked to
reactive arthritis
caused by bacterial infection
what are the signs of reactive arthritis
eye inflammation diarrhoea lower back pain scaly patches in genitals flaky skin on soles swelling in knee, heel or ball of foot
