Pathology Flashcards
collagen affected in Ehlors Danlos syndrome
type 3 (III) collagen
features of Ehlors Danlos syndrome
increased skin elasticity
hypermobility of joints
subarachnoid haemorrhage
easily bruised
mitral valve prolapse, aortic regurgitation, aortic dissection
angioid retinal streaks
collagen affected in osteogenesis imperfecta
type I collagen due to decreased synthesis of pro-alpha 1 or pro-alpha 2 collagen peptides
Ehlors-danlos syndrome - autosomal dominant or recessive?
dominant
osteogenesis imperfecta - autosomal dominant or recessive
dominant
what are does the bloods show in osteogenesis imperfecta?
calcium, phosphate, PTH and ALP are all normal
features of osteogenesis imperfecta
easily broken bones
blue sclera
deafness due to otosclerosis
dental imperfections
what is acquired ichthyosis?
acquired skin condition where the skin is dry and scaly - derived from greek word meaning ‘fish’ as it is like fish scales
causes of acquired ichthyosis
lymphoma i.e. hodgkins
malnutrition
leprosy
kaposi’s sarcoma
features associated with ankylosing spondylitis
the 6 A’s;
anterior uveitis
apical fibrosis
achillies tendonitis
amyloisosi
AV node block
aortic regurgitation
and cauda equina syndrome
peripheral arthritis (in females)
how does ankylosing spondylitis present ?
young adult male with stiff/painful lower back of insiduous onset
worse in the morning, eases with exercises
pain at night relieved with getting up
benign bone tumours
osteoma
osteochondroma
giant cell tumour
xray appearance of giant cell tumour
double bubble or soap bubble appearance
most common location of giant cell tumour
epiphysis of long bones
most common location of osteoma
skull
most common location of osteochondroma
Metaphysis of long bones
what bone tumour is associated with onion skin appearance ?
ewings sarcoma
x ray features of osteosarcoma
codmans triangle (due to periosteal elevation)
sunburst pattern
risk factors for osteosarcoma
pagets disease
radiotherapy
Rb gene (hence association with retinoblastoma)
genetic defect associated with ewings sarcoma
associated with T(11:22) translocation which results in EWS-FLI1 gene
what bone tumour is a small blue cell tumour?
ewings sarcoma
antibodies associated with dermatomyositis
anti-jo (histadine tRNA ligase)
anti-mi 2
anti-signal regognition peptide (SRP)
risk factors for gout
increased production:
- myeloproliferative/ lymphoproliferative disorders
- cytotoxic drugs
- severe psoriasis
- red meat
decreased excretion:
- chronic kidney disease
- drugs i.e. diuretics
- lead toxicity
both:
- alcohol
- obesity
features of langerhans cell histocytosis
punched out osteolytic lesions
biopsy feature of langerhan cell histocytosis
CD1a and S100 protein
grooved nuclei
what is langerhan cell histocytosis
over proliferation of langerhan cells which are specialised dentritic cells which present antigens to T lymphocytes
genetic defect in marfans syndrome
mutation of FBN1 gene on chromosome 15 that codes for protein fibrilin 1
xray findings in osteoarthritis
reduced joint space
subchodnral cysts
subchondral sclerosis
osteophytes
xray findings in rhuematoid arthritis
loss of joint space
juxta-articular osteoporosis
periarticular erosions
subluxation
most important risk factors for osteoporosis
steroid therapy
history of parental hip fracture
rheumatoid arthritis
low BMI
current smoker
alcohol excess
drugs that can worsen osteoporosis
SSRI’s
PPI’s
antiepileptics
long term heparin therapy
glitazones
aromatase inhibitors i.e. anastrazole
what causes pellagra ?
niacin deficiency
features of pellagra
the 3 D’s
Dermatitis
Diarrhoea
Dementia
risk factors for pellagra
isoniazid therapy
alcoholics
pathophysiology of pemphigus vulgaris
autoimmune caused by an antibody against desmoglein-3
what population is pemphigus more common in ?
ashkenazi jewish
what is nikolsky’s sign and what condition is it associated with?
pemphigus
- spread of bullae after applying horizontal, tangential pressure to the skin
pityriasis rosacea presentation
initial heralds patch which then spreads, has a fir tree appearance
what virus is associated with pityriasis rosacea
HSV-7
what composite is found in pseudogout
calcium pyrophosphate dihydrate crystals
features of pseudogout vs gout on microscopy
pseudogout - weakly positive birefringet rhomboid shaped crystals
gout - negative birefringet rod shaped crystals
antibodies associated with sjogrens
anti-Ro (70%)
anti-La (30%)
ANA (70%)
RF (50%)
conditions associated with SCC of skin
actinic keratosis
bowens disease
3 features of Colle’s fracture
transverse fracture of the radius
1 inch proximal to radio-carpal joint
dorsal displacement and angulation