1. Dr Sarah Levy Consultant Rheumatologist CUH
Psoriatic Arthritis - Practical guide to diagnosis and initial management
Dr Sarah Levy
Consultant Rheumatologist CUH

2. Contents Epidemiology Clinical presentation and subtypes
Pitfalls and tips for diagnosis and management

3. Epidemiology 1.3-2.2 % population have psoriasis
10-30% of those develop psoriatic arthritis ( PsA)
Approximately 1600 patients in Croydon.
Up to 40% of those with extensive skin disease develop PsA.

4. Epidemiology Affects men and women equally
Incidence peaks between the ages of 30 and 55 years.
Underdiagnosed
European and North American study of 285 patients with psoriasis
Reviewed by rheumatologist
Of those diagnosed with PsA (41%) had not been previously given the diagnosis

5. Clinical presentation
In many chronic progressive and erosive
Course may be erratic, with flare-ups and remissions
Can range from mild synovitis, synovitis causing severe progressive erosion, enthesopathy, inflammatory tendinopathy ( 1 little toe!)
When the spine is affected the condition may be indistinguishable from Ankylosing Spondylitis.

6. Relationship with skin disease – very little !
The relationship between the skin and joint manifestations is unclear.
60% of people with the condition the psoriasis precedes the arthritis
25% of people the arthritis appears first
15% of people the symptoms occur simultaneously
People with severe arthritis can have little or no skin disease, and vice versa
Flare-ups of 2 conditions do not necessarily coincide.

7. Medical school teaching – 5 types of PsA
1. Oligoarticular and asymmetrical ( 50%) – often 1 knee plus ankle/ Achilles.
2. Symmetrical ( 5-10%) – often looks like seronegative rheumatoid
3. Arthritis mutilans ( 5%)

8. 5 Types of psoriatic arthritis
4. DIP joint only often associated with nail disease
(5-10%)
5. Spinal disease ( 20-40%)

9. Real Life
Combination of everything….. At presentation and varying during natural history of condition.
Major manifestation is enthesopathy/dactylitis/ tendonitis

10. Enthesopathy/Dactylitis – not a feature of Rheumatoid

11. Achilles Enthesopathy/Tendonitis

14. Enthesopathy/ Dactylitis/ Tendinopathy
Enthesopathy can occur at any site with an entheses and often co-exists with Inflammatory tendinopathy
Inflammatory tendinopathy/ enthesopathy is common and can be recurrent and widespread– Patient with bilateral tennis elbow / Achilles/lateral thigh tendons.

15. Enthesopathy/ Dactylitis/ Tendinopathy
Can present with widespread pain, tender points, normal bloods (relatively avascular structure so unlikely to cause rise in inflammatory markers) and normal MRI/ US ( difficult to image).
Can be an important differential for Fibromyalgia and a cause for failure to treat pain in patients despite suppression of synovitis with biologics/DMARDS.

16. Difficult to diagnose and common
Some tips to aid detection in Primary Care
Some Pitfalls

17. Screening tool – PEST. Designed to be used in dermatology clinics
     
Screening tool – PEST.
Designed to be used in dermatology clinics
Unlikely to be fully sensitive but it is a start.

18. Tips and pitfalls in Psoriatic Arthritis - detection.
Flare/ presentation can be precipitated by stress ( as per psoriasis)
2 young men developed PsA following being stabbed in Brixton.
Flare/ presentation can be precipitated by injury
Koebnerisation – i.e. knee flare if falls onto knee/ bilateral sacroiliitis in ice skater who fell 4 months post fall.
PsA commoner if have scalp psoriasis
DIP arthritis/ enthesopathy often associated with nail onycholysis

19. Tips and pitfalls in Psoriatic Arthritis - detection.
No association with activity of skin lesions and may precede the development of psoriasis.
Family history of psoriasis is often found in those without personal history of psoriasis.
Hips often affected and damaged
Person who has had hip replacements in their 40’s and 50’s may have PsA
Erosive osteoarthritis esp. DIP may be Psoriatic ( you don’t get the films and the report may not differentiate unless reported by MSK radiologist)
Bloods (ESR/CRP) normal in at least 50% of patients

20. Tips and Pitfalls - treatment
Steroid often not as effective as in rheumatoid ( often higher doses needed)
NSAIDs often more effective but beware metabolic syndrome in patients
In plaque psoriasis beware offset flare of psoriasis after steroids – can be severe
Patient with erythrodermic psoriasis after depomedrone im
Low vitamin D is commoner than in controls and I have seen joints improve with Vitamin D replacement.
PsA -Can cause rapid destruction of joints
Rapid destruction of hip joint while switching from MTX to LEF

21. Hospital Treatment
Local steroid injections can be very helpful and give lasting relief
Correct biomechanical stresses esp. weight and feet
In Rheumatology Methotrexate/Leflunomide/ Sulphasalazine most commonly used DMARDs
New DMARD Apremilast PD4 inhibitor
Biologics anti TNF/Ustekinumab/Secukinumab
Enthesopathy is harder to treat than synovitis even with biologics.

22. Chronic widespread pain
In Fibromyalgic patient with psoriasis consider Generalized Enthesopathy/ tendinopathy
With normal bloods and subtle imaging/ examination findings its very difficult to differentiate.
One study found an overall prevalence of depression of 78.9% in patients with psoriasis
Keep this in mind when assessing patients who have psoriasis in whom you are considering a diagnosis of Fibromyalgia

23. Fibromyalgia vs Enthesopathy

25. Questions..