Rheumatoid arthritis is a chronic, autoimmune inflammatory arthropathy, affecting an estimated 1% of the population in the UK. 

 

Epidemiology

  • Age of onset: 30-50 years of age
  • Females are at highest risk (3F: 1M)
  • Genetics: Associated with HLA-DR4

 

Clinical Features

  • Autoimmune symmetrical polyarthritis, presenting with painful joints – particularly the small joints of the hands and feet
  • RA inflammation spares the DIP joints
  • Morning stiffness, lasting an hour or longer
  • On examination: 
    • Positive squeeze test
    • Boutonniere and swan neck deformity indicate advanced disease
    • Swelling around the joint - ‘boggy’
    • Warmth
    • Rheumatoid nodules - firm swelling, mostly found on the extensor surfaces

 

Investigations

  • RA is a clinical diagnosis, but the following investigations can support the diagnosis.
  • Bloods:
    • 1st line: Rheumatoid factor - positive in 7/10 people with RA
      • An IgM antibody which reacts with IgG
      • Prognostic marker - high RhF levels associated with progressive disease
    • 2nd line: If RhF negative, measure anti-cyclic citrullinated peptide antibodies (anti-CCP)
    • CRP/ESR are commonly elevated
  • XR: Juxtaarticular osteoporosis

 

Management of RA flares

  • 1st Line: Short-term treatment with steroids
    • Intra-articular glucocorticoid if localised flare
    • IM glucocorticoid if IA is not possible - methylprednisolone, triamcinolone 
    • PO glucocorticoid if not practical to give IM
  • Consider offering an NSAID for short term symptomatic relief with PPI

 

Long-term Management of RA

  • 1st Line: Commence DMARD monotherapy at diagnosis
    • Methotrexate, leflunomide or sulfasalazine
    • Consider hydroxychloroquine in the case of palindromic rheumatism
    • Consider co-prescribing a steroid as bridging therapy while commencing Tx. 
  • 2nd line: Offer additional DMARDs in combination if treatment aims are not achieved
  • 3rd line: If the disease has not responded to a combination of DMARDs, consider offering biological DMARDs in combination with methotrexate
    •  TNF-inhibitors - etanercept, infliximab, adalimumab 
    • Monoclonal antibody therapy - rituximab, abatacept

  

DMARDs - adverse effects

  • Methotrexate
    • Myelosuppression - monitor FBC
    • Liver cirrhosis - monitor LFTs
    • Methotrexate pneumonitis, pulmonary fibrosis
  • Sulfasalazine
    • Oligospermia, interstitial lung disease, heinz body anaemia
  • Leflunomide
    • Hypertension, liver impairment, interstitial lung disease
  • Hydroxychloroquine
    • Ophthalmic disease - retinopathy, corneal deposits 

 

Rheumatoid arthritis in Pregnancy

  • Safe DMARDs during pregnancy: Sulfasalazine, Hydroxychloroquine (SHafe in pregnancy)
    • AVOID Methotrexate & leflunomide 

  

Extra-articular manifestations of rheumatoid arthritis

  • Respiratory manifestations
    • Pulmonary fibrosis
    • Pulmonary nodules
    • Pleural effusions (exudative)
    • Caplan syndrome: Massive fibrotic nodules occur following exposure to coal dust
    • Bronchiolitis obliterans
  • Ocular manifestations
    • Keratoconjunctivitis sicca – Dry, red irritated eyes, blurred vision and visual fatigue
      • The most common ocular complication
    • Scleritis – red + painful
    • Episcleritis – red
    • Corneal ulcers, keratitis
  • Others:
    • Accelerated cardiovascular disease – high risk of ischaemic heart disease in RA
    • Osteoporosis 
    • Depression
    • Felty’s syndrome
    • Amyloidosis AA

  

Palindromic Rheumatism

  • Relapsing/remitting monoarthritis of large joint
  • Management: DMARDs as above - hydroxychloroquine