Patient explanation

Gold standard case presentation

Rheumatoid arthritis

Rheumatoid arthritis is a common and useful station for station 5, as patients have good visual signs as well as a plethora of symptoms. In this case, a diagnosis of rheumatoid arthritis ha already been established, and the patient is experiencing a flare of her disease. However, cases can range from a new diagnosis, through to early management options, exacerbations to complications and side effects. This case touches on a few of these aspects. We will discuss all of the above now.

The diagnosis of rheumatoid arthritis (RA) is well established, as the most common systemic inflammatory arthritis, with a 1% global prevalence. Average age of onset is between 30-50 years of age.

Risk Factors

• Women > men
• Older age
• Positive family history for RA / autoimmune inflammatory disease
• Active or previous smoking history

Symptoms and Signs

• Multiple join pain and stiffness (lasting > 1 hour)
• Smaller joints like proximal interphalangeal joints, metacarpophalangeal joints and wrists more commonly involved
• Synovitis with boggy swelling
• Systemic symptoms of fatigue, weight loss and even chronic low-grade fever

A scoring system based upon four broad areas, with a score of 6 and above indicates RA (American College of Rheumatology / European League Against Rheumatism Classification Criteria):

• Joint Involvement (1 large / 2-10 large / 1-3 small / 4-10 small / > 10 any joins with at least one small)
• Serology (RF – negative, low positive, high positive)
• Acute Phase Reactants (CRP and ESR)
• Duration of Symptoms (over/under 6-weeks)

Investigations

• Rheumatoid Factor – RF
  • Can be positive or negative (+ in 50-80%)
• Anti-citrulinated protein Ab – Anti-CCP (sensitivity ofo 95%)
• Anti-nuclear Ab (positive or negative)
• CRP and ESR (positive or negative)
  • Can be used to follow disease remission
• Baseline blood tests (full blood count, renal and liver function, bone profile)

Differential Diagnosis

• Systemic lupus erythematosus
• Systemic sclerosis
• Psoriatic arthritis
• Polymyalgia rheumatica
• Temporal arteritis (especially if fever and weight loss is significant)

Also need to consider arthropathy related to other autoimmune systemic conditions such as inflammatory bowel disease.

Systemic Manifestations

• Cardiovascular
  • atheroscerlosis (up to 3x higher risk)
  • pericarditis
  • vasculitis
• Ocular
  • scleritis
  • keratoconjunctivitis
• Bone marrow
  • amyloidosis
  • Felty’s syndrome
• Neurological
  • neuropathy
  • cervical myelopathy
• Pulmonary
  • lung fibrosis
  • pulmonary nodules
  • pleural effusions
• Sjögren’s syndrome

Management

Management requires a multidisciplinary approach between physicians, specialist nurses, pharmacists, physiotherapists, occupational therapists and primary care practitioners.

Initially, steroids were the mainstay of treatment, however, they cause significant side effects and the advent of DMARDs (disease modifying anti rheumatic drugs) has been a game changer for people with RA.

All patients should be encouraged to exercise, as this has been shown to have a beneficial effect on disease progression and disability.

Methotrexate (MTX)

The primary DMARD used is first-line now for RA. It is a non-biologic agent and inhibits dihydrofolate reductase, as such, folic acid supplementation is required to be taken for the entire duration of treatment with methotrexate. It is taken once weekly. Side effects include hepatic damage (from mild reversible transaminitis to rare corrhosis), teratogenesis (hence avoid in women of child-bearing age, alopecia, nausea, diarrhoea and oral ulcers.

Methotrexate has been shown to improve life expectancy in RA as well as reduce radiographic features of the disease. Monotherapy with MTX has been found to be less efficacious than dual therapy with with a biologic agent (such as anti-TNF agents).

Leflunamide

This is an alternative to MTX, if the latter is not tolerated or causes severe complications. It inhibits pyrimadine synthesis and also has teratogenic side effects as well as potentially causing gastrointestinal upset, which are more common than with MTX.

Combination therapy of two or more DMARDs has better outcomes than monotherapy. First and second line treatment is non-biologic therapy with the above or hydroxychloroquine, sulfasalazine or minocycline. If these do not work, biologic agents such as adalimumab or etanercept can be used. Unlike non-biologic agents, combination therapy with 2 or more biologic agents is not recommended due to adverse effects.

Corticosteroids

Corticosteroids are of use for pain control, but due to the side effects from prolonged therapy, should only be used for short-term management. DMARDs are the mainstay of treatment.

Side effects of prolonged steroid use include:

• Type 2 diabetes
• Weight gain
• Hypertension
• Osteoporosis and fractures
• Thinning skin with easy bruising
• Gastrointestinal ulceration
• Visual disturbance from cataracts or glaucoma
• Poor sleep
• Depression

Prognosis

Remission can occur in up to half of patients, but exacerbations, such as in this case, do occur. More severe disease tends to occur with those that are serology positive, with raised inflammatory markers and a higher number of affected joints. Radiological evidence of joint erosion is also a poor sign as is systemic disease.

References

2013 NICE Rheumatoid Arthritis Guidelines

NICE Rheumatoid Arthritis in adults: management

British Society for Rheumatology

Arthritis Research UK