Acute join pain (oxford clin cases)

Question 1

In an acutely painful joint what diagnosis must you exclude because it is a medical emergency?

Answer 1

Septic arthritis

Question 2

What are articular causes of joint pain in one joint (ie monorthritis)

Answer 2

Septic arthritis
Trauma
Gout
Pseudogout

Question 3

What are periarticular causes of joint pain in one joint (ie monorthritis)

Answer 3

Ligment injury
Tendinitis
Bursitis

Question 4

What type of pain is likely with an acute joint if its worse on movement and better with rest?

Answer 4

Non inflammatory

Question 5

What are some common diagnoses for joint pain if the pain comes on acutely?

Answer 5

Septic arthritis
Gout/pseudogout
Trauma

Question 6

What are some common diagnoses for joint pain if the pain comes on insidiously?

Answer 6

Tendonitis

Bursitis

Question 7

What are common risk factors for gout?

Answer 7

Being on thiazide diuretics
Recent heavy alcohol intake
Chronic renal failure and renal stones
Chemotherapy 
Previous gout

Question 8

What are some common risk factors for septic arthritis?

Answer 8

Being immunocompromised (diabetes, HIV, steroid use)
Prosthetic limbs

Question 9

What does joint pain involving multiple joints sequentially indicate is the diagnosis?

Answer 9

Rheumatic fever

Gonococcus

Question 10

What does joint pain involving multiple joints simultaneously indicate is the diagnosis?

Answer 10

Rheumatoid arthritis

Psoriatic arthritis

Question 11

What drugs might predispose someone to gout?

Answer 11

Thiazide diuretics
Low dose aspirin
Ciclosporin

Question 12

What drug predisposes someone to osteoporosis?

Answer 12

Steroids

Question 13

What questions would you ask in the history when someone presents with acute joint pain? Explain why you’d ask them

Answer 13

Was the pain acute?- likely septic arthritis, gout, pseudogout
Is the pain insidious?- likely bursitis and tendonitis
Is the pain chronic?- likely osteoarthritis
Do they have any risk factors for gout?- thiazide diuretics, recent alcohol misuse, renal failure, renal stones, previous episode
Have they had any recent trauma to the knee?
Do they have any risk factors for septic arthritis?- immunocompromised (diabetes, on steroids, HIV) or prosthetic joints
Have they had any recent GI infection?
Are they at risk of any STIs?- gonocccus might present this way
Are other joints involved?- sequentially= gonococcus or rheumatic fever, simultaneously= rheumatoid or psoriatic arthritis

Question 14

How are articular conditions likely to present?

Answer 14

With diffuse swelling over the whole joint which will be red, hot and tender. Pain will be present during both passive and active movement

Question 15

How are periarticular conditions likely to present?

Answer 15

There will be a focal point of swelling eg the tendon or the bursa
Pain will be worse on active movement

Question 16

What do articular and periarticular mean?

Answer 16

Articular= to do with the joint
Periarticular= around the joint

Question 17

What are tophi and what are they a sign of?

Answer 17

They are deposits of urate crystals, they can break through the skin
They are a sign of chronic gout

Question 18

What are some signs of psoriasis or psoriatic arthritis that are found on the nails?

Answer 18

Onycholysis
Subungal hyperkeratosis
Pitting

Question 19

What is uveitis and when is it seen?

Answer 19

Swelling of the middle layer of the eye- they eye will be red, painful, have diminished vision and may have an irregularly shaped pupil
It is seen in HLA-27 positive arthropathies

Question 20

What sign may be seen in the mouth in IBD (especially Crohn’s)?

Answer 20

Ulcers

Question 21

What non articular features may you find on examination in someone with a condition causing acute monoarticular pain? Explain why they would be seen

Answer 21

Nails- onycholysis, subungal hyperkeratosis, pitting (all= psoriasis/ psoriatic arthritis)
Eyes- uveitis (HLA 27 positive arthropathy)
Mouth- ulcers (IBD, especially Crohn’s which is associated with arthropathy)
Skin- rashes, tophi, rheumatoid nodules
Lungs- signs of fibrosis eg crackles at the end of inspiration, clubbing due to inflammatory arthropathy)

Question 22

What investigation is done to rule out septic arthritis?

Answer 22

Athrocentesis

Question 23

What is tested in the lab when an arthrocentesis sample is sent there?

Answer 23

Culture- takes a few days
Microscopy- cell count and crystals
Gram stain

Question 24

What type of crystal is found in gout?

Answer 24

Urate

Question 25

What type of crystal is found in pseudogout?

Answer 25

Calcium pyrophosphate

Question 26

What shape and birefringent are crystals in gout?

Answer 26

Needle shaped | Negatively birefringent

Question 27

What shape and birefringent are crystals in pseudogout?

Answer 27

Rhomboid shaped | Positively birifringent

Question 28

What characteristics will arthrocentesis in someone with infection have?

Answer 28

It will be cloudy High WCC High neutrophils Bacteria visible

Question 29

What does blood on arthrocentesis suggest?

Answer 29

Trauma or fracture

Question 30

What does fat on arthrocentesis suggest? Why?

Answer 30

Fracture- the fat comes from the bone marrow

Question 31

What investigations might you do for someone who presents with acute joint pain? Explain why you would do each one

Answer 31

Athrocentesis- first line investigation to make an accurate diagnosis Bloods: FBC, ESR, CRP- to check for inflammation Anti CCP, ANA antibodies/ rheumatoid factor- look for arthropathies Serum urate- raised in those with chronic gout Xray of joint- useful in identifying fractures, effusion, necrosis, eroision of joint surfaces, crystals MRI of joint- useful in visualising soft tissue injury which can't be seen on x ray

Question 32

In gout what type of cells in athroentesis make up most of the WCC when someone has gout?

Answer 32

Polymorphonuclear cells (PMNs)

Question 33

What joints are most commonly affected in gout?

Answer 33

Most common= big toe | Next most common= knee

Question 34

How is acute gout managed?

Answer 34

First line colchicine NSAIDs alongside colchicine Corticosteroid injections

Question 35

In whom is colchicine contraindicated?

Answer 35

Patients with renal or hepatic impairment

Question 36

In whom are NSAIDs contraindicated?

Answer 36

Peptic ulcer disease, chronic renal failure, asthmatics (although sometimes asthmatics can tolerate low dose NSAIDs and just need to be warned to look for signs of exacerbation)

Question 37

What medication is contraindicated in gout and why? When might patients still take it?

Answer 37

Aspirin because it reduces urate excretion | Patients may still take it if the cardiovascular risk outweighs the treatment for gout

Question 38

What methods are used to combat chronic gout?

Answer 38

Decrease urate production Increase urate excretion Increase urate degeneration These can all be done with different medications

Question 39

What might precede septic arthritis and why?

Answer 39

Trauma to the area | It may be a route of infection

Question 40

What might aspirate look like from a joint when someone has septic arthritis?

Answer 40

Yellow and turbid (like pus)

Question 41

What should you immediately do in terms of treatment if you suspect a patient has septic arthritis

Answer 41

Start broad spectrum antibiotics and analgesia

Question 42

On what movements will a patient with bicipital tendonitis have pain?

Answer 42

Shoulder flexion Elbow flexion Supination

Question 43

What is reiter's syndrome?

Answer 43

Reactive arthritis that usually follows gastroenteritis or a STI

Question 44

What triad of symptoms indicates Reiter's syndrome and how do you remember it?

Answer 44

Can't see, can't pee, can't climb up a tree Uveitis Urethritis Arthritis

Question 45

What are features of osetoarthritis on xray and how do you remember them?

Answer 45

``` LOSS: Loss of joint space Osteophytes Subchondral sclerosis Subchondral cysts ```

Question 46

What is the most common causative agent of septic arthritis?

Answer 46

Staphylococcus aureus