Pathology (cortex ones better) Flashcards
what are autoimmune conditions characterised by
presence of autoantibodies
what autoantibody is present in rheumatoid arthritis
rheumatoid factor
what is rheumatoid arthritis
autoimmune disease, typically causing inflammation of the joints but can have many manifestations
what is seen histologically in aute RA
pannus formation- inflammatory granulation tissue
hyperplasic/ reactive synovium
what is seen in chronic RA
cartilage is destroyed by inflammatory process, loss of joint space= fibrosis, deformity
what autoantibodies are seen in SLE
ones directed at structural parts of DNA- 95% ANA+ve
what are inflammatory arthritides
inflammatory diseases that affect the joints and surrounding structures
what is seen acutely is histology of a inflammatory arthritides
oedema, fibrin, reactive features in synovial cells
what is seen chronically is histology of a inflammatory arthritides
lymphocytes and plasma cells
what autoantibody in scleroderma
anti centromere, antitelomere
what autoantibody in dermatositis
anti jo
what is uric acid and why can it reach high concentrations
the end product of purine synthesis. Adenine and guanine and purine based, anything that increases turnover of these is associated with a crystal arthropathy
what are the two types of crystal arthropathy
gout and psuedo gout
what causes gout
hyperuricaemia- either increased urate production (e.g. increased cell turnover- psoriasis, cancer or tumour lysis) or reduced excretion (drug side effect- thiazide diuretics)
what is the pathological manifestation of gout
precipitation of crystals (due to reduced solubility) usually in joints (due to lower temps) elicit inflammatory reaction
what are the clinical implications of gout
causes secondary degeneration changes in joint, deposition in soft tissue causes gouty trophy. renal diseases (stones and direct deposition in tubules and interstitium)
what is seen in cytology of gout
needle shaped crystals seen in cross polarised light
what is seen histologically in gout
amorphous eosinophillic debris and inflammation (giant cells).
NOT crystals as lost during tissue processing
what crystal causes pseudogout/ chrondrocalciosis
calcium phosphate (rhomboid shaped crystals)
what are features of pseudo gout
older patient, larger joint. usually asymptomatic but can cause range of joint pain
what is pagets disease
when there is an abnormailty of bone turnover- increased oestoclastic activity
what is the cause of pagets
unknown, genetic components, RANKL, viral infection
what are the three stages of pagets
osteolytic, mixed and burnt out
what is the net result of pagets
thick excess bone with abnormal reversal lines- mosaic pattern
pain- microfractures or nerve compression (bone expansile)
enlargement and abnormal shape
increased metabolism- heat, warm skin, AV shunt, high output cardiac failure
secondary malignancy (osteosarcoma)
what is histologically in the initially phases of a fracture
haematoma (fibrin mesh), influx of inflammatory cells, cytokine release, recruitment of osteoprogenitor cells from periosteum and medulla cavity (repair cells)
what is seen histologically a week after a fracture
callous, organised haematoma, early recruitment and bone remodelling
what can cause delay healing of a fracture
poor blood supply
poor nutrition
too much movement
too great a distance
what is a pathological fracture
when bone is not normal before fracture e.g. oestoperosis/ tumours (benign/ malignant)
what are cancers that commonly metastasise to bone
lung, kidney, breasts prostate
what does bone metastasis look like
most oestolytic- bone is resorbed and appears radiolucent
prostate appears as osteosclerotic- areas of opacity (more dense)
what are myeoma/plasmacytoma
malignant proliferation of plasma cells, causes bony lesion
what is avascular necrosis
bone infarction, causes 10% of hip fractures
what causes avascular necrosis
trauma, alcohol main causes
steroid injection, dysbarism, sickle cell diseases, infection
what does avascular necrosis look like histologically
wedge shaped area of discolouration, often subcortical
creeping substitution (new bone grows over old dead bone)
what is osteoarthitis
a degenerative disease cause by mechanical injury due to abnormal load distribution, previous fracture or anatomical abnormality
what are the changes of osteoarthritis
damage to cartilage surfaces then later damage to the underlying bone
what is seen histologically in osteoarthitis
fibrillation, erosion/ eburnation (subchondral sclerosis), subchondral cyst formation (synovial fluid accumulation), osteophyte (disorganised bone formation limits joint movement), loss of joint space
what causes osteophytes
cortical bone thickens to cope with load, rapid bone remodelling= abnormal outgrowths
what is subchondral sclerosis a sign of
eburnation
describe karotyping
culture cells and then arrest during cell division- provides overview of chromosomal structure but will not detect small or subtle lesions
what is FISH useful for
to find known translocations- if signals move together then translocation
what does immunohistochemistry do
places a pigment on an antibody to target a protein to see whether it is present
describe ganglion cysts
lump peripheral and near a joint capsule or tendon sheath, common around the wrist
degenerative change within connective tissue. not a true cyst no epithelial lining
what is seen histologically in in a ganglion cyst
space with myxoid material, secondary inflammatory changes
where are common places for superficial fibromatoses
dupuytrens, knuckle pads, plantar, penile (peyronie’s)
what causes dupuytrens
idiopathic- associated with alcohol and anticonvulsants
what is deep fibromatoses
mesenteric or pelvic tumours
desmoid tumours- deeper in viscera of body
association with gardner’s syndrome
what is pigmented villonodular synovitis
giant cell tumour that you get in large joints
where do you get giant cell tumours of tendon sheath
digits
describe angiolipoma
usually multiple and peripheral, vascular with fibrin thrombin, painful
what is a leiomyoma
smooth muscle tumour
what are the main proteins in smooth muscles
actin, desmin and caldesom
who gets cardiac phabdomyomas
kids
what are the forms of skeletal muscle malignant tumours
embryonal rhabdomyosarcoma (children), alveolar (young adults), pleomorphic (young adults)
do cartilage sarcomas affect the paediatric population
no
what is more worrying, a cartilage tumour in the extremities or central body
central more likely to be sarcoma
what is gardners syndrome
multiple bone lesions
what is characteristic of osteoid osteoma
nidus (focus of infection), associated with tenderness
what is an osteoma
benign tumour of the bone
who and where do you get osteosarcoma
usually paediatric age group, long bones
what is a pathology diagnostic sign of osteosarcoma
any malignant tumour that produces osteoid is oestosarcoma until proven otherwise
where do osteosarcomas metastasise to first
lung fields
who gets ewings sarcoma, what is it like
children and adolescents
destructive, rapildy growing and highly malignant
what do the ewings family of tumours look like
small round blue cell tumours
what cancer is commonly missdiagnosed as sarcoma
carcinoma
what is nodular fascitis
reactive lesion, affects any age group, rapid growth, snall
what is seen histologically in nodular fascitis
chaotic appearance, haemorrhage, pseudocystic spaces, large atypical cells, frequent mitoses, normal mitoses
what is myositis ossificans
reactive lesion, small, preceeds trauma
what are rheumatoid nodules
common, elbow, reactive lesion
