Psoriatic arthritis

DIP joint InvolvementNail changes

Psoriatic arthritis

Nail pitting in psoriatic arthritis

Psoriatic arthritis

Deforming arthritis

Psoriatic arthritis- pseudorheumatoid

Looks like RABut RF –psoriasis

What is this diagnosis?

Osteoarthritis

What is this diagnosis?

Osteoarthritis

Beware the rare but serious….

• Conditions that may present with inflammatory arthritis like RA– Polymyositis, dermatomyositis: should have

muscle weakness, RF can be + low titre, do CK– Vasculitis eg Wegener’s granulomatosis:

always do U/A, renal function, RF-, ANCA +, may be very resistant to usual RA therapy

– Neoplastic conditions: resistant to usual RA therapy

Case history 5

• 25 year old man, episode of diarrhoea, 3 weeks later onset of knee swelling, followed by ankle swelling and achilles tendonitis

• Unable to walk in mornings due to pain and stiffness

• By midday joints “warmed up”• No conjunctivitis, no dysuria, diarrhoea

settled, no rash

Investigations

• FBC normal

• ESR 53, CRP 36

• UEC normal

• RF negative

• ANA negative

• Stool cultures- negative

Clinical picture

Left knee effusion

Achilles tendonitis

Diagnosis

• Sero-negative inflammatory arthritis reactive arthritis– Think of this group if past history of diarrhoea

(eg salmonlla), dysuria (eg chlamydia), sore throat (strep)

– Typical joint distribution: lower limb asymmetrical, knee, ankle, enthesitis with achilles tendonitis, plantar fasciitis, sausage toes (dactylitis)

Case history 6

• 35 year old man

• 3 year history of low back, buttock pain

• Worse in the morning, improves with walking around.

• Wakes him in early hours of the morning

• Past history of red eye many years ago, treated with steroid drops

Examination and investigations

• No peripheral joint synovitis

• Back movements: some limitation of lumbar flexion, nil else

• FBC normal

• ESR, CRP normal

• Diagnosis?

• Further investigations?

Diagnosis

• Inflammatory back pain

• Sero-negative spondyloarthropathy

• Do pelvic Xray to look at sacro-iliac joints

• HLA-B27 antigen– Not diagnostic test for ankylosing spondylitis– 10% normal population HLA-B27+– 90% AS HLA-B27+

Sacri-iliitis

Psoriatic arthritis

Ankylosing spondylitissubtype

Joint distribution

• Symmetrical, small joint arthritis, MCP, PIP, wrists, MTPs +/- other joints– Think RA, psoriatic, SLE or viral

• Asymmetrical, predominantly lower limb, ankle knee, enthesitis– Think sero-negative spondyloarthropathies– Psoriatic, Reactive, ankylosing spondylitis

• Sacro-iliac (buttock) pain, spinal stiffness– Think sero-negative spondyloarthropathies, eg ankylosing

spondylitis