Spondyloarthropathies

Question 1

What does seronegative arthropathy mean?

Answer 1

Seronegative arthropathies are:

• RF negative
• arthritis leads to increased bone formation across the joint (–> decreased joint function)
• associated with HLA B27 (Caucasians, esp. Scandinavians and Inuits; rare in Australian Indigenous and African populations)
• enthesitis (at tendon insertion point) common (cf. synovitis in RA)

enthesitis leads to bony deposition, as opposed to synovitis which leads to bony erosions

Ankylosing spondylitis, Axial psoriatic arthritis, Reactive arthritis, Colitic arthritis, Juvenile arthritis, Acute anterior uveitis.

Question 2

Outline the Modified New York Criteria for Ankylosing Spondylitis:

Answer 2

CLINICAL:

1. LBP and stiffness >3 months. (Improves with exercise, not relieved by rest).
2. Spinal movement limited globally (in sagittal and frontal planes - cf. mechanical BP where limited side-to-side, but not front-to-back)
3. Chest expansion limited ( approx. 50% will have developed AS by 10 years

Radiological:
>grade 2 bilateral sacroiliitis or grade 3 unilateral

(grade 2 is minimal changes, grade 3 is evidence of alkalosis, grade 4 is complete loss of sacroiliac joint, just replacement by a line of fused bone)

DEFINITE diagnosis = radiographic and at least 1 clinical

Question 3

List non-vertebral manifestations of spondyloarthritis:

Answer 3

• Skeletal: hip / peripheral / chest wall arthritis
• Tenosynovitis - Achilles and plantar fasciitis
• Iritis
• Respiratory complications- chest call and thoracic spine fusion
• Osteoporosis (ignore the lumbar spine figures for BMD)

Rare: pulmonary fibrosis (classically upper lobe), amyloid, aortitis, IgA nephropathy, cauda equina syndrome

Question 4

What proportion of healthy Australians carry HLA-B27?

Answer 4

about 10%! This means there are >95% of B27 positive patients are healthy

Question 5

What is the most common extra-spinal manifestations of Ank Spond?

Answer 5

anterior uveitis/iritis complicates about 40% of AS!

characterised by: unilateral redness, pain, photophobia and itching.

It is usually unilateral (can alternate from side to side though)

generally is not vision threatening

treatment is with topical steroids or mydriatics
sometimes can trial anti-TNF (but etanercept doesn’t work well for this!)

Question 6

what are determinants of Ank Spond disease severity?

Answer 6

cigarette smoking
age of onset <16 years
lower SES

B27 pos progresses just as fast as B27 negative

Question 7

What are the treatments of Ank Spond?

Answer 7

Education

In the exam:

1. PT
2. NSAIDs

Amitriptyline - this is to assist with fatigue. AS patients have fatigue for two reasons - high levels of circulating TNF and also because back pain wakes them a lot at night

Sulphasalazine and MTX (for peripheral arthritis more often
I/a steroids - for peripheral arthritis OR for fluoroscopically guided SI joint ‘roid injections

Anti-TNF

Surgery - hip replacement

Question 8

What can cause reactive arthritis?

Answer 8

Post-infectious

• ureteric infection
• • chlamydia
• • mycoplasma
• post-dystenry
• • shigella
• • salmonella
• • C. diff
• • vibrio
• • Yersinia

Question 9

what is the clinical presentation of Reactive arthritis?

Answer 9

most cases are a low grade fever, with lower limb, asymmetric oligo-arthritis

there can also be dactylitis
enthesitis in the Achilles, plantar and infrapatellar

sacroiliitis ~40% by 15 years

there can be mucocutaneous lesions like:

• mouth ulcers
• penile lesions that are punched out ulcer lesions that are NON PAINFUL
• Keratoderma blenorrhagica (pustular psoriasis, but in truth it is nasty looking psoriasis with significant desquamation)

Question 10

Causes of erythema nodosum?

Answer 10

SORE SHINS

Streptococci
OCP
Rickettsia
Eponymous (Bechet),

Sulfonamides
HLA-B27 (AS)
IBD
NHL
Sarcoidosis

Question 11

Causes of pyoderma gangrenosum?

Answer 11

1. IBD
2. RA
3. AS
4. HIV
5. leukaemia
6. monoclonal gammopathies

Question 12

what is the treatment of reactive arthritis?

Answer 12

no really certain

it is mostly NSAIDs

hopefully the majority are in remission by 12 months

Question 13

Describe the arthritis pattern in enteropathic colitis associated arthritis

Answer 13

there are 2 major patterns:

1. large joint pauciarticular relapsing-remitting associated with IBD and uveitis
2. Symmetric polyarthritis - chronic and course is independent of other disease features

Question 14

is there any association with AS and IBD?

Answer 14

About 10% of AS cases have IBD

About 10% of IBD cases have AS

however a large number of AS patients will have terminal ileitis on biopsy

Question 15

What percentage of patients with psoriasis will have arthritis too?

how related is the skin and joint disease?

Answer 15

about 20%

the relationship between the two diseases is pretty poorly correlated. the skin disease usually precedes joint disease

Question 16

what are the changes of psoriatic nail disease?

Answer 16

approximately 80% of patients with PsA have nail disease

the common changes are:
pitting
subungual hyperkeratosis
discolouration
dystrophy
onycholysis (ridging)

more commonly associated with DIPJ disease

Question 17

what are the 5 patterns of psoriatic arthritis?

Answer 17

axial disease (SI)

DIP predominant

symmetric RA mimic

asymmetric oligoarthritis

arthritis mutilans

Question 18

what are the treatments of Psoriatic arthritis?

Answer 18

NSAIDS
Gold, penicilliamine
plaquenil
MTX

anti-TNF

IA ‘roids

Question 19

what can happen with the co-administration of trimethoprim and methotrexate?

Answer 19

this is a high risk situation

they are both “anti-folates” and can lead to severe bone marrow suppression

Question 20

In Ank Spond, syndesmophyte formation is most likely to be first seen in what part of the spine?

Answer 20

Thoraco-lumbar junction is the most common starting point

Question 21

what would be the reason for an unexpectedly elevated BMD reading for the lumbar spine?

if the patient had RA

Answer 21

there are two possibilities

osteoporotic crush fracture would cause an elevated reading

lumbar spondylopathy would also cause elevation (patients with Ank Spond have falsely elevated)

Question 22

What is the Schober test?

Answer 22

this assesses the amount of lumbar flexion

mark 2 spots on the lumbar spine, about 15 cm apart, and measure the distance between.

normal is >5 cm

Question 23

what are the important stages of gonococcal arthritis?

Answer 23

classically this is pustules over the hand and an mono, or oligoarthritis - more commonly lower limb joints

there is an initial septicaemia stage, where there is disseminated infection. At this stage one has to ensure that there is not a septic joint

after that, about 2-3 days later, there is a mono- or oligo-arthritis

Question 24

does flucloxacillin do anything to LFTs?

Answer 24

It can cause an entity called flucloxacillin cholestasis

this is rare, but cholestatic jaundice is the prominent feature

it has a delayed onset and can take weeks to resolve