MSK and Rheum - Seronegative Spondyloarthropathies (Ankylosing Spondylitis, Psoriatic Arthritis, Reactive Arthritis)

Question 1

Seronegative Spondyloarthropathies - what are the Spondyloarthropathies?

Answer 1

1. ankylosing spondylitis
2. psoriatic arthritis
3. reactive arthritis
4. enteropathic arthritis (associated with IBD)

Question 2

Seronegative Spondyloarthropathies - what are the common features?

Answer 2

Associated with HLA-B27

Rheumatoid Factor NEGATIVE, hence seroNEGATIVE

Peripheral arthritis, usually asymmetrical

Enthesopathy: e.g. Achilles tendonitis, plantar fasciitis

Question 3

Seronegative Spondyloarthropathies - what is the definition for enthesopathy?

Answer 3

The place where a tendon or ligament meets your bone is called an enthesis, plural, entheses.

Enthesopathy is an umbrella term for conditions that affect these connection points

Question 4

Ankylosing Spondylitis - what is it?

Answer 4

Inflammatory condition mainly affecting the spine that causes progressive stiffness and pain

Question 5

Ankylosing Spondylitis - what are the key joints that are affected?

Answer 5

Sacroiliac joints

Joints of the vertebral column

Question 6

Ankylosing Spondylitis - how does it commonly present?

Answer 6

1. Young man with lower back pain and stiffness of insidious onset
2. Stiffness usually worse in the morning, improves with exercise
3. Patient may experience pain at night, improves on getting up

Question 7

Ankylosing Spondylitis - what are the features you might find on clinical examination?

Answer 7

1. Reduced lateral flexion
2. Reduced forward flexion - Schober’s test - a line is drawn 10 cm above and 5 cm below the back dimples (dimples of Venus), distance between two lines should increase by more than 5 cm when patient bends as far forward as possible
3. Reduced chest expansion

Question 8

Ankylosing Spondylitis - what can the inflammation cause in sacroiliac joints and vertebral column?

Answer 8

Inflammation causes pain and stiffness in these joints

Can progress to fusion of the spine and sacroiliac joints

Fusion of the spine leads to classical “bamboo spine” finding on spinal xray

Question 9

Ankylosing Spondylitis - what are the other extra features? (the A’s)

Answer 9

• Apical fibrosis
• Anterior uveitis
• Aortic regurgitation
• Achilles tendonitis
• AV node block
• Amyloidosis
• and cauda equina syndrome
  
  • peripheral arthritis (25%, more common if female)

Question 10

Ankylosing Spondylitis - investigations?

Answer 10

Bloods - typically CRP and ESR raised, not always though

Check for HLA-B27, but not diagnostic as its sensitivity and specificity are around 90%

XRAY

MRI - most sensitive

Question 11

Ankylosing Spondylitis - what findings might you see on XRAY?

Answer 11

• X rays, most helpful in established disease, may be normal in early stages of disease
• Squaring of vertebral bodies
• Syndesmophytes (bony bridges between adjacent vertebrae)
• Sacroiliitis
• Bamboo spine, single central radiodense line related to ossification of supraspinous and interspinous ligaments which is called dagger sign
• Eventually fusion of the joint
• Subchondral sclerosis of sacroiliac joint

Picture is an example of bamboo spine with the dagger sign going through the middle of it

Question 12

Ankylosing Spondylitis - what is the non-pharmacological and pharmacological management?

Answer 12

Non-pharmacological:

1. Exercise
2. Physiotherapy
3. Avoid smoking

Pharmacological:

1. 1st line -NSAIDs
2. DMARDs, such as sulfasalazine and methotrexate are more useful in patients with enthesitis than axial symptoms, they do not improve spinal inflammation
3. Failure to control symptoms with NSAIDs/severe disease, TNF-alpha inhibitors such as Infliximab

Question 13

Psoriatic Arthritis - what is it?

Answer 13

inflammatory arthritis associated with psoriasis

Question 14

Psoriatic Arthritis - what happens to the joints?

Answer 14

mild stiffening and soreness in the joint

or joint can be completely destroyed in a condition called arthritis mutilans

Question 15

Psoriatic Arthritis - when does it present?

Answer 15

Within 10 years of the skin changes first occurring

Question 16

Psoriatic Arthritis - what are the 5 different types of joint presentation (classification)?

Answer 16

1. Asymmetrical oligoarthritis - inflammation of 5 or fewer joints, most common (60%)
2. Symmetrical polyarthritis - inflammation of more than 5 joints in a symmetrical fashion (similar to rheumatoid arthritis), most common
3. Spondylitis - inflammation of the joints in the spine
4. Distal interphalangeal joint arthritis
   
   1. Arthritis mutilans - a severe deformity where there is destruction of bone and collapse of digits.

Question 17

Psoriatic Arthritis - what are the 5 different joint presentations (classification)?

Answer 17

1. Asymmetrical oligoarthritis - inflammation of 5 or fewer joints, most common
2. Symmetrical polyarthritis - inflammation of more than 5 joints in a symmetrical fashion (similar to rheumatoid arthritis), most common
3. Spondylitis - inflammation of the joints in the spine
4. Distal interphalangeal joint arthritis
5. Arthritis mutilans - a severe deformity where there is destruction of bone and collapse of digits.

Question 18

Psoriatic Arthritis - what is Onycholysis?

Answer 18

Onycholysis - separation of the nail from the nail bed

Question 19

Psoriatic Arthritis - what is enthesitis?

Answer 19

• Enthesitis (inflammation of the entheses, which are the points of insertion of tendons into bone)

Question 20

Psoriatic Arthritis - what tool do you use to screen?

Answer 20

Psoriasis Epidemiological Screening Tool (PEST)

Question 21

Psoriatic arthritis - what is the classic finding seen on XRAY?

Answer 21

Pencil in cup deformity

Appearance results from periarticular erosions and bone resorption

Question 22

Psoriatic Arthritis - management?

Answer 22

1. NSAIDs for pain
2. DMARDs - methotrexate
3. Anti-TNF medications (etanercept, infliximab or adalimumab)
4. Last line - Ustekinumab

Question 23

Reactive arthritis - what is it?

Answer 23

It is an arthritis characterised as a triad of arthritis, urethritis and conjunctivitis, brought on by a recent infective trigger, such as an STI (e.g. chlamydia), or dysenteric illness (e.g. salmonella)

Question 24

Reactive arthritis - what is the way to remember the triad?

Answer 24

‘Can’t see, pee or climb a tree’

conjunctivitis

urethritis

arthritis

Question 25

Reactive arthritis - how do you differentiate it from septic arthritis?

Answer 25

Septic arthritis has infection in the joint, however in reactive arthritis there is no infection in the joint, no organism can be recovered from joint

Question 26

Reactive arthritis - what are the most common dysenteric and STI infective triggers

Answer 26

Post-dysenteric:

Shigella flexneri
Salmonella typhimurium
Salmonella enteritidis
Campylobacter

STI:

Chlamydia trachomatis

Question 27

Reactive arthritis - what is the time frame for the disease to present, and for it to last for?

Answer 27

Typically develops within 4 weeks of initial infection

Symptoms generally last around 4-6 months

Question 28

Reactive arthritis - what two skin changes can occur?

Answer 28

• Circinate balanitis - painless vesicles, dermatitis of the head of the penis
• Keratoderma blenorrhagica - waxy yellow/brown papules on palms and soles

Question 29

Reactive arthritis - investigations?

Answer 29

Bedside:

• stool MC&S
• urethral / cervical swabs for chlamydia

Bloods:

• Inflammatory markers - raised
• Is a seronegative spondylarthropathy - should be rheumatoid factor -ve

Aspirate the joint and send a sample for gram staining, culture and sensitivity testing to exclude septic arthritis

Question 30

Reactive arthritis - management?

Answer 30

Episodes usually benign, resolve within weeks or months with NSAIDs and corticosteroid injections

Recurrent cases may require DMARDs or anti-TNF medications

Question 31

Dactylitis - what is it, and which diseases does it present in?

Answer 31

Dactylitis refers to a global swelling of a finger or a toe

Presents commonly in reactive and psoriatic arthritis

Sign that can be used to differentiate from other arthritic conditions