Arthritis, spondyloarthropathies

Question 1

what gene mediates RA

Answer 1

HLA-DR4

Question 2

pathophysiology of RA?

Answer 2

synovial inflammation and hypertrophy due to unknown cause
APC presents antigen to T cells, activating macrophages and pro inflammatory mediators. also activates B cells which secrete RF to activate osteoclasts to cause bone erosion, chondrocytes to cause cartilage destruction and synoviocytes for hypertrophy

Question 3

what is the hypertrophied synovium called?

Answer 3

pannus

Question 4

true/false - smoking has increased risk of RA

Answer 4

true

Question 5

RF/anti-CCPis more specific for RA

Answer 5

anti-CCP

Question 6

why would a patient with RA have a raised alk phos

Answer 6

because osteoclast activity causes raised alk phos

Question 7

what would you see on a typical x ray for RA

Answer 7

soft tissue swelling
periarticular osteopaenia
erosion

Question 8

RA complications in the hands?

Answer 8

swan necking of fingers

ulnar deviation of MCPs

Question 9

DAS 28 score of <2.6 is indicative of

Answer 9

remission

Question 10

DAS 28 score of 2.6-3.2 is indicative of

Answer 10

low activity

Question 11

DAS 28 score of 3.2-5.1 is indicative of

Answer 11

moderate activity

Question 12

DAS 28 score of >5.1 is indicative of

Answer 12

active disease

Question 13

most commonly affected joints of osteoarthritis

Answer 13

hands, knees, hips

Question 14

pathophysiology of osteoarthritis

Answer 14

localised loss of hyaline cartilage and remodelling of adjacent bone with osteophyte formation at joint margin
thickening of synovium
may lead to synovial thickening, sclerosis and subchondral cyst

Question 15

risk factors for osteoarthritis

Answer 15

genetics 
ageing 
females 
obesity 
joint injury 
occupation
joint malalignment 
reduced muscle strength

Question 16

what joints are affected in localised OA

Answer 16

hips, interphalangeal joints, facet joints of lower cervical and lower lumbar spines

Question 17

what joints are affected in generalised OA

Answer 17

spinal/hand joints and at least 2 other regions

DIP, thumb bases, first MTP, lower lumbar and cervical facet, knees and hips

Question 18

how does OA appear on X ray

Answer 18

marginal osteophytes
loss of joint space
subschondral sclerosis
subchondral cysts

Question 19

complications of cervical OA

Answer 19

pain
occipital headaches
impinged nerve roots due to osteophytes

Question 20

complications of lumbar OA

Answer 20

osteophytes can cause spinal stenosis

Question 21

what mineral causes gout

Answer 21

monosodium urate

Question 22

what mineral causes pseudogout

Answer 22

calcium pyrophosphate

Question 23

what mineral causes hydroxyapatite

Answer 23

calcium phosphate

Question 24

what factors may cause increased urate production in gout

Answer 24

inherited enzyme defects 
psoriasis 
haemolytic disorders 
alcohol 
high purine diet - high sugar, red meat, seafood

Question 25

what factors may cause decreased urate excretion in gout

Answer 25

``` chronic renal impairment volume depletion hypothroidism diuretics cyclosporin ```

Question 26

pathophysiology of gout

Answer 26

purines from diet and DNA/RNA converted to xantine, converted to plasma urate and excreted. gout is deposition and precipitation of crystals in joints. causes phagocytosis by monocytes and neurophils. neutrophils rupture to release lysosymes and monocytes secrete pro inflammatory mediators and proteases to cause inflammation/tissue damage

Question 27

gout is usually a mono/polyarthropathy

Answer 27

monoarthropathy

Question 28

what is classically seen in chronic gout

Answer 28

tophi

Question 29

true/false - in acute gout serum urate is always increased

Answer 29

false - not always as it is so sudden onset

Question 30

if you looked at monosodium urate under a microscope, how would it appear

Answer 30

negatively birefringent needle shape

Question 31

indications for prophylactic therapy for gout?

Answer 31

``` 2 or more gout attacks in a year gouty trophi uric acid calculi chronic renal impairment heart failure chemotherapy ```

Question 32

what type of drugs are allopurol, febuxostat

Answer 32

xanthine oxidase inhibitors | prevent conversion of purine to xanthine

Question 33

name a few uricosuric drugs and what ypu must always check before prescribing

Answer 33

sulfinpyrazone, proenecid, benzbromazone | check kidney function

Question 34

true/false - you must start gout prophylaxis during acute attack

Answer 34

no! do it after 2 weeks as if its done too soo it can cause another acute attack

Question 35

you want to reach the serum urate target in a susceptible patient who has had gout before. she is on allopurol. she hasnt yet reached target serum levels. what other drug must she be on

Answer 35

an NSAID, until serum target reached

Question 36

what is the serum target for gout

Answer 36

300-360umol/L

Question 37

what joints does calcium pyrophosphate deposition disease affect

Answer 37

knee, ankle, wrist

Question 38

calcium pyrophosphate- how does it appear under a microscpe

Answer 38

positively birefringent with rhomboid shape

Question 39

causes of pseudogout

Answer 39

``` osteoarthritis age amyloidosis trauma hypothyroidism hyperparathyroidism haemochromatosis ```

Question 40

hydroxyapatite - what joint does it affect and what happens

Answer 40

crystal deposition in and around joint, most commonly shoulder release of collagenases and proteases acute, rapid deterioration

Question 41

what is soft tissue rheumatism

Answer 41

localised pain and inflammation/damage to ligaments, tendons, muscles or nerves near joint

Question 42

what is the most common area for soft tissue rheumatism

Answer 42

shoulder

Question 43

who is joint hypermobility more common in

Answer 43

``` women marfans ehlers danlos children under 14 ```

Question 44

what is modified beighton score

Answer 44

extension of 9 joints to look for hyperextension | +ve if 4 or more joints

Question 45

what are spondyloarthropathies

Answer 45

inflammatory arthritides with involvement of spine and joints in HLA B27 individuals

Question 46

mechanical vs inflammatory back pain

Answer 46

mechanical - relief by rest, worse at end of day, worse with activity inflammatory - worse on rest, better on activity, morning stiffness

Question 47

shared features of spondyloarthropathies

Answer 47

``` sacroiliac and spinal involvement inflammatory arthritis enthesitis dactylitis uveitis mucocutaneous lesions no rheumatoid nodules rare aortic incompetence or heart block ```

Question 48

features of AS

Answer 48

``` axial arthritis anterior uveitis aortic regurg apical fibrosis amyloidosis/IgA nephropathy achilles tendinitis plAntar fasciitis ```

Question 49

what is tragus to wall

Answer 49

patient to stand with back, buttock and heel to wall. Try to push head against wall. Patients with AS will struggle to do so due to spinal fusion

Question 50

what is modified schobers test

Answer 50

test for lumbar spinal fusion. Get patient to bend forward without bending knees. Measure 10cm up from dimples of venus and then whilst bending. Should be 15 cm ish

Question 51

what would an x ray of AS reveal

Answer 51

sacroiliitis syndesmophytes bamboo spine reduced bone density in later disease

Question 52

what would an x ray of PsA look like

Answer 52

marginal erosion/whiskering pencil in cup deformity osteolysis enthesitis

Question 53

most common infections causing reactive arthritis

Answer 53

chlamydia | salmonella, shigella, yersina

Question 54

triad in reactive arthritis

Answer 54

urethritis conjunctivitis/uveitis arthritis

Question 55

what is enteropathic arthritis associated with and where does it occur

Answer 55

IBD | knee, ankle, elbow, wrist, spine, hip, shoulder