Spondyloarthropathies Flashcards
What does seronegative arthropathy mean?
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.
Outline the Modified New York Criteria for Ankylosing Spondylitis:
CLINICAL:
- LBP and stiffness >3 months. (Improves with exercise, not relieved by rest).
- Spinal movement limited globally (in sagittal and frontal planes - cf. mechanical BP where limited side-to-side, but not front-to-back)
- 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
List non-vertebral manifestations of spondyloarthritis:
- 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
What proportion of healthy Australians carry HLA-B27?
about 10%! This means there are >95% of B27 positive patients are healthy
What is the most common extra-spinal manifestations of Ank Spond?
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!)
what are determinants of Ank Spond disease severity?
cigarette smoking
age of onset <16 years
lower SES
B27 pos progresses just as fast as B27 negative
What are the treatments of Ank Spond?
Education
In the exam:
- PT
- 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
What can cause reactive arthritis?
Post-infectious
- ureteric infection
- chlamydia
- mycoplasma
- post-dystenry
- shigella
- salmonella
- C. diff
- vibrio
- Yersinia
what is the clinical presentation of Reactive arthritis?
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)
Causes of erythema nodosum?
SORE SHINS
Streptococci
OCP
Rickettsia
Eponymous (Bechet),
Sulfonamides HLA-B27 (AS) IBD NHL Sarcoidosis
Causes of pyoderma gangrenosum?
- IBD
- RA
- AS
- HIV
- leukaemia
- monoclonal gammopathies
what is the treatment of reactive arthritis?
no really certain
it is mostly NSAIDs
hopefully the majority are in remission by 12 months
Describe the arthritis pattern in enteropathic colitis associated arthritis
there are 2 major patterns:
- large joint pauciarticular relapsing-remitting associated with IBD and uveitis
- Symmetric polyarthritis - chronic and course is independent of other disease features
is there any association with AS and IBD?
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
What percentage of patients with psoriasis will have arthritis too?
how related is the skin and joint disease?
about 20%
the relationship between the two diseases is pretty poorly correlated. the skin disease usually precedes joint disease
what are the changes of psoriatic nail disease?
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
what are the 5 patterns of psoriatic arthritis?
axial disease (SI)
DIP predominant
symmetric RA mimic
asymmetric oligoarthritis
arthritis mutilans
what are the treatments of Psoriatic arthritis?
NSAIDS
Gold, penicilliamine
plaquenil
MTX
anti-TNF
IA ‘roids
what can happen with the co-administration of trimethoprim and methotrexate?
this is a high risk situation
they are both “anti-folates” and can lead to severe bone marrow suppression
In Ank Spond, syndesmophyte formation is most likely to be first seen in what part of the spine?
Thoraco-lumbar junction is the most common starting point
what would be the reason for an unexpectedly elevated BMD reading for the lumbar spine?
if the patient had RA
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)
What is the Schober test?
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
what are the important stages of gonococcal arthritis?
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
does flucloxacillin do anything to LFTs?
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
