rheumatoid arthritis

Question 1

what is rheumatoid arthritis?

Answer 1

An chronic systemic inflammatory disease.

autoimmune disease associated with antibodies to Fc portion of IgG (rheumatoid factor) an Anti CCP

Question 2

what is the pathogenesis of RA?

Answer 2

pathogenesis involves citrullination of self antigens which are then recognised by T and B cells, which then produce RF and anti CCP

stimulated macrophages and fibroblasts release TNFa

inflammatory cascade lead to proliferation of synoviocytes (result in joint swelling). These grow over the cartilage and lead to restriction of nutrients and the cartilage is damaged

activated macrohages stimulate osteoclast differentiation contributing to bone damage

Question 3

what the typical history of a patient with RA?

Answer 3

• female
• 30-50years old
• present with progressive, peripheral and symmetrical polyarthritis
• usually affects MCPs/PIPs/MTPs and typically spares DIPs
• may affect any joint inc hips/knees/shoulder/ c spine
• history > 6 weeks
• morning stiffness >30 mins duration
• commonly have fatigue/malaise

Question 4

what is usually found in examination of a patient with RA?

Answer 4

• soft tissue swelling and tenderness
• ulnar deviation/ palmar subluxation of MCPs
• swan neck and boutonniere deformity to digits
• rheumatoid nodules, most common at elbow
• check median nerve due to carpal tunnel association

Question 5

what investigations are done in RA?

Answer 5

• RF and anti CCP
• FBC - normocytic anaemia. WCC is concerns re septic arthritis
• inflammatory markers elevated
• x ray changes. USS/MRI more sensitive in early disease
• other investigations guided by history and exam e.g may need PFTs and HRCT chest if lung involvement e.g pulmonary fibrosis

Question 6

how is RA treated?

Answer 6

• DMARD monotherapy, usually methotrexate. Consider a combination ( leflunomide, hydroxychloroquine, sulfasalazine)
• steroids (PO/IM or intraarticular)
• symptom control with NSAIDs (and PPI cover)
• consider biologics if disease still severe after combination DMARDs e.g Anti TNF agents like etanercept
• Non drug e.g OT/PT, podiatry, psychological

Question 7

what are the x ray features of RA?

Answer 7

Loss of joint space

periarticular erosions

soft tissue swelling

subluxation

Question 8

what are some extra articular manifestations of RA?

Answer 8

• carpal tunnel
• elevated CBD risk
• anaemia
• pleural disease
• pulmonary disease
• Sjogrens

Question 9

what are the ADRs of DMARDs?

Answer 9

immunosuppression due to pancytopenia

increases susceptibility to infection and neutropenic sepsis