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
what is a smiths fracture
distal radius fractre
fall on an outstretched hand backwars or fall on flexed wrist
causes volar angulation of the radius
colle’s vs smiths fracture
colle’s = dorsal angulation of radius
smiths = volar angulation of radius
bartons fracture
distal radius fracture (colle’s/smiths) with associated radiocarpal dislocation
monteggia fracture
proximal radioulnar dislocation with associated ulnar fracture
galezzia fracture
distal radioulnar dislocation with associated radial shaft fracture
galezzia vs monteggia fracture?
galezzia = dislocation of distal radioulnar joint with radial shaft fracture
monteggia = proximal radioulnar dislocation with ulnar fracture
how does avascular necrosis of the scaphoid occur with a fracture
blood supply from the dorsal carpal branch of the radial artery is compromised
whats shown on biopsy of skin SCC
keratin pearls
What condition is cANCA associated with?
Granulations with polyangitis
What condition is pANCA associated with?
Eosinophilic granulomatosis with polyangitis (and others)
- microscopic polyangitis
- Ulcerative colitis
- primary sclerosing chiantis
- anti-GBM disease
What antigen is associated with Behcet’s syndrome?
HLA-B51
Symptoms of behcet’s syndrome
Oral ulcers
Genital ulcers
Anterior uveitis
What is behcet’s syndrome?
Presumed autoimmune inflammation of arteries but aetiology yet to be determined
More common in men
Age 20-40
HLA-B51
Family history 30%
Unhappy triad
ACL
Medial medical (although lateral is more common)
Medial collateral ligament
What is osteopetrosis
Genetic condition where there is failure of normal bone respoptioj due to defect in osteoclast activity
Thickened dense bone = fractures
Thickened foramina = palsies and paralysis
Bone forms in bone marrow = pancytopenia
Xray shows bone on bone appearance (diffuse sclerosis)
Osteomalacia vs rickets
Both caused by impaired mineralisation of bone
Osteomalacia - in cortical bone
Rickets - in epiphysis of growth plate in children
What is osteitis deformans?
Paget’s disease
Impaired turnover of bone resulting in weak bones
Isolated rise in ALP
Skull thickening = increase in head sis
Deafness due to skull deformity
Increased risk of osteosarcoma
Increased blood flow due to increased arteriovenous shunts = risk of high output cardiac failure
Causes of avascular necrosis
Casts bend legs
Glucocorticoids
Alcohol
Sickle cell
The Bends (caisson/decompression disease)
Legg calf perthes
Gaucher dissase
SUFE
Lab value in osteomalaci/rickets
Low calcium and phosphate
High PTH
High ALP
Most common location of ostesarcoma and ewings?
Osteosarcoma - metaphysis long bones
Ewings - diaphysis
What HLA anigen is associated with rheumatoid arthirtis ?
HLA-DR4
Appearance of gout and pseudogout under light micorscopy
Gout - yellow when light parallel, blue when perpendicular
Pseudogout - blue when light parallel
Most common organism in osteomyelitis of prosthetic joint?
Staph. Epidermidis
Classic triad of reactive arthritis
Uveitis
Urethritis
Arthritis
“Cant see, pee or bend knee”
Causative organisms for reactive arthritis
She caught every student cheating yesterday and overreacted
Shigella
Campylobacter
E.coli
Salmonella
Chlamydia
Yersinia
Reacted - reactive arthritis
Antibodies associated with SLE
Anti-dsDNA
Anti-Sm
Antiphospholipid
What type of hypersensitivity reaction is SLE?
Type 3 (III)
Antibodies associated with anti-phospholipid syndrome
Lupus anticoagulant
Anti cardiolipin
Anti-B2 glycoprotein I
Pathophysiology of myasthenia gravisvs lambert-eaton myasthenic syndrome
Myasthenia gravis - Ab against post synaptic Ach receptor
Lambert-eaton - Ab against the pre synaptic Ca channel
Antibodies associates with scleroderma
Limited: anti-centromere
Diffuse: Anti sci-70 and anti-RNA
Features of langerhan cell histocytosis on microscopy
Racket shaped granules
(Birbeck granules)
Melanoma is derived from what cells
Neural crest cells
Neuroblastomas share a similar embryological origin to what type of tumour
Melanoma
Both origionate from neural crest cells
(Neuroblastomas from chromaffin cells of adrenal medula which are derived from neural crest cells)
what muscles may become weak in carpal tunnel syndrome
opponens pollicis
abductor pollicis longus
flexor pollicis longus
gene affected in achrondoplasia
mutation in cell signalling in the FGFR3 gene
(fibroblast growth factor receptor 3 - important for cartillage development)
achondroplasia inheritance pattern
autosomal dominant
achondroplasia features
shortened stature
shortened limbs, large head
kyphoscoliosis
lumbar lordosis
gait - trunk leaning posteriorly when heel strikes the floor
due to damage to what nerve and muscle it supplies
inferior gluteal nerve supplying the maximum muscle
what cell type is mostly involved in the pathogenesis of OA
macrophages and cytokines
what cell type is involved in the phathogenesis of inflammatory conditions like RA, lupus etc
T and B cells
gram negative, aerobic, oxidase positive
pseudomonas
causative organisms in osteomyelitis with risk factors;
- IVDU
- sickle cell
- developing countries
IVDU - gram negatives (e.coli, pseudomonas)
sickle cell - salmonella, staphylococci
developing countries - TB
gram negative, oxidase negative bacillus
salmonella
gram positive, catalyse positive bacterium
staphylococci
germline mosaicism and a condition its found in
autosomal dominant condition found in a patient whose parents dont have the condition
Ehlors danlos syndrome
uniparental disomy and a condition example
2 copies of a chromosome come from one parent
angleman syndrome, prader willi syndrome
perimysial inflammation with perifascicular atrophy
dermatomyositis
muscle atrophy with internalised nuclei
myotonic dystrophy
slow relaxation of hand grip
myotonic dystrophy
Endomysial infiltration of inflammatory infiltrate
polymyositis
what nerve root supplies the long thoracic nerve
C5-C7
HLA antigen - multiple sclerosis
HLA-DR2
(2 parts to the name = DR2)
HLA antigen - graves disease
HLA-DR3 (graves - 3 slaves)
HLA antigen bechet’s disease
HLA-B51
histopathology findings in polymyositis
CD8 T cell inflammation
macrophages
necrotic myofibrils
staph aureus type of bacterium
gram positive, coagulase positive, catalse positive aerobe
IgM antibody against the Fc portion of IgG (IgM anti-IgG)
RHEUMATOID ARTHRITIS
antibodies against the nuclear protein that links sister chromatids
limited scleroderma (CRET syndrome)
rimmed vacuoles and mononuclear cell (CD8) infiltrates
inclusion body myositis
inclusion body myositis features
weakness of quadriceps and finger flexor muscles
elevated CK, normal ESR/CRP
location of ewings vs osteosarcoma
ewings = diaphysis of long bones and pelvis
osteosarcoma = metaphysis long bones (FAMILY HISTORY common)
pathological organism for rheumatic fever
group A strep (GAS)
pathophysiology of rheumatic fever
antibody cross-reactivity against host and foreign antigens
(molecular mimicry)
location of nerve root lesion which causes loss of achillies tendon reflex
S1
loss of biceps reflex - nerve damaged?
musculocutaneous
muscles affected in erbs palsy
supraspinatous, infraspinatous, deltoid, biceps brachii
what type of skin rash is found in anti phsopholipid syndrome
lavido reticularis
what nerve is damaged with loss of biceps reflex
musculocutaneous nerve (C5-C7)
what nerve is damaged with difficulty flexing elbow
musculocutaneous (C5-C7)
what muscles are affected in erbs palsy
supraspinatous
infraspinatous
biceps brachii
deltoid
gene affected with causes multiple digits
syndactyly = HOX gene mutation (FGFR1)
pathophysiology of cleft palate
failure of closure of maxillary and medial nasal prominences
features of inclusion body myositis
weakened hand grip
elevated CK
rimmed vacuoles with mononuclear cell infiltrates
risk factor for achondroplasia
increasing paternal age
short limbs and large head
achondroplasia
due to genetic defect in FBGF3
