Giant Cell Arteritis (GCA)

 

• Definition

  • Vasculitis of large and medium vessels, especially cranial branches of arteries arising from aortic arch
  • 50% of patients also have polymyalgia rheumatica.
  • Aka temporal arteritis.

• Signs and symptoms

  Pain:

  • Unilateral throbbing headache.
  • Scalp tenderness e.g. on combing hair.
  • Jaw claudication.

  Other symptoms:

  • Systemic symptoms: malaise, fever.
  • Painless, sudden visual loss, usually monocular, but can be bilateral. Transient loss initially (amaurosis fugax), but permanent loss is a potential complication. Usually due to anterior ischaemic optic neuropathy.
  • Morning stiffness and shoulder pain due to polymyalgia rheumatica.
  • Chest or abdominal pain from aortitis (15%).

  Signs:

  • Tender temporal artery.
  • Weak or uneven temporal artery pulse.
  • Pale, swollen optic disc.

• Risk factors

  • Polymyalgia rheumatica.
  • Age >50 years.
  • Northern climates.

• Investigations

  Bloods:

  • Inflammatory markers: ↑ESR, ↑CRP. The sensitivity of both is around 85%.
  • FBC: ↑platelets, ↓Hb.
  • ↑Alk phos.

  Temporal artery biopsy:

  • Mononuclear/granulomatous infiltration.
  • Don't delay treatment while awaiting biopsy.

• Management

  • Immediate high dose prednisolone. Continued for 1 month, then tapered down over 6-12 months.
  • Add tocilizumab or methotrexate if steroids ineffective or causing side effects.
  • Adding aspirin is thought to reduce the risk of visual loss and stroke. Optimal length of therapy unclear.
  • PPI for gastric protection while on steroids and aspirin.