Psoriatic Arthropathy

Question 1

What percentage of patients with psoriasis develop psoriatic arthropathy?

Answer 1

10-20%

Question 2

What screening tool is used to diagnose psoriatic arthritis?

Answer 2

PEST screening tool. (Psoriatic Epidemiological Screening)

1. Have you ever had a swollen joint?
2. Has a doctor ever told you that you have arthritis?
3. Do your fingers or toieails have holes or pits?
4. Have you ever had a pain in your heel?
5. Have you had a finger or toe that was completely swollen and painful for no apparent reason?

A score of 3 or more suggests psoriatic arthritis.

Question 3

Who are more affected, males or females?

Answer 3

They are equally affected.

Question 4

What are the different types of psoriatic arthropathy?

Answer 4

• Rheumatoid-like polyarthritis (Most common ~ 40%)
• Asymmetrical oligoarthritis= ~ 30% (typically hands and feet)
• Sacroilitis
• DIP joint disease (10%)
• Arthritis mutilans (most severe - telescoping fingers)

Question 5

How do you treat psoriatic arthropathy/

Answer 5

Treat as you would Rheumatoid Arthritis

Question 6

What has a better prognosis, RA or Psoriatic arthritis?

Answer 6

Psoriatic arthritis

Question 7

Answer 7

Question 8

Answer 8

X-ray showing some of changes in seen in psoriatic arthropathy. Note that the DIPs are predominately affected, rather than the MCPs and PIPs as would be seen with rheumatoid. Extensive juxta-articular periostitis is seen in the DIPs but the changes have not yet progressed to the classic ‘pencil-in-cup’ changes that are often seen.

Question 9

A 45-year-old man attends surgery with joint problems.

Over the past few weeks he has woken with swelling of the small joints of both hands and severe morning stiffness which takes about three hours to improve. He gets the odd twinge in other joints and has previously had a swollen knee.

His medication includes allopurinol and Cade compound (for his severe dandruff). He is rheumatoid factor negative.

Which of the following is the most likely diagnosis?

• Gout
• Haemochromatosis
• Palindromic rheumatism
• Polymyalgia rheumatism
• Psoriatic arthropathy

Answer 9

Psoriatic arthropathy

• The description could fit for RA, but acute psoriatic arthropathy is sometimes indistinguishable clinically. The key here is that this is a seronegative arthritis and there is a further clue in that he is likely to have scalp psoriasis. Often there are no skin lesions, but there are usually nail changes.Around 25% of RA is seronegative as well, but it is the whole picture that suggests the diagnosis.
• PMR - morning stiffness but shoulder girdle usually affected in older peope.
• Palindromic Rheumatism - diagnosis of exclusion. Sporadic and amy progress to RA.
• Haemochromatosis - pain in small joints but no acute swelling.
• Gout - unlikely as on allopurinol.