
Contents
Introduction
Epidemiology
- F > M – approx 2 -3 :1
- Higher incidence in Northern European countries
- Usually only seen in patients aged >50
- 20% chance of permanent visual loss
- About 50% of patients also have concurrent polymyalgia rheumatica
- Only about 15% of those with PMR get GCA
- A small percentage of patients also have disease in the large arteries, which can cause intra-thoracic and abdominal manifestations
Clinical features
- Rare under 50
- Generalised headaches
- Scalp tenderness – 25% of cases
- May be apparent when combing hair or resting head on a pillow
- Claudication of the jaw – 25% of cases
- Painless temporary or permanent visual loss – if more than one of the occipital or temporal arteries is affected
- Other visual disturbance may also be apparent, e.g. double vision
- ANY visual disturbance is critical
- Sudden blindness can occur without any of the other symptoms
- Generalised malaise
- Fever
- Tiredness
Examination
- Perform an eye exam
- Visual acuity
- Visual fields
- Eye movements
- Pupillary light reaction
- Perform fundoscopy – check optic disc and retinal vessels
- Examine temporal arteries
- May feel thickened or hardened
- May have absent pulses
- Normal artery examination does NOT exclude the diagnosis
Investigations
Bloods:
- ESR and CRP
- Any elevation of either suggests a diagnosis of GCA
- 5-10% of patients will have normal ESR and CRP – especially those with blindness only
- Normal ESR and CRP makes GCA unlikely but does not rule out the diagnosis
- FBC
- Normocytic / normochromic anaemia
- Platelets may be elevated
LFT’s
- Low albumin
- ↑ALP
- ↑y-GT
Temporal arterial biopsy
- This is the definitive diagnostic test. You should take the sample before or within 7 days of starting steroids (if these are given)
- Histological features include:
- Intimal hypertrophy
- Inflammation of the intima
- Degredation of the internal elastic lamina
- Giant cells, lymphocytes and plasma cells in the internal elastic lamina
Treatment
If suspected GCA – start corticosteroids immediately, and refer to ophthalmology for temporal artery biopsy.
No visual loss
- Prednisolone PO – 40-60mg /day – can be single or divided doses
- This can dramatically reduce symptoms within 24 hours.
- Continue for a minimum of 4 weeks – and at least until symptoms AND inflammatory markers have resolved
- Then – taper the dose
- Reduce daily dose by 10mg every 2 weeks until 20mg daily
- Then reduce by 2.5mg every 2 weeks until 10mg daily
- Then reduce by 1mg daily every 2 weeks
- Continue until steroids have ceased, provided no relapse of symptoms
- Dose adjustments are often guided by specialist
- Methotrexate may be considered as an adjunct in patients who do not respond will to steroids
- Start low dose aspirin – 100mg daily PO
- This reduced the risk of a thrombotic event in the affected arteries
- Follow up:
- After 2-3 days
- At 1, 3 and 6 weeks
- Every 3 months if on continuing treatment
- Manage relapses by initially increasing to the previous dose of prednisolone. If symptoms severe – return to the starting dose.
Visual loss
- IV methylprednisolone 0.5 – 1g daily for three days
- Then switch to oral prednisolone and other measures as above
Other factors
- The disease is likely to settle after 12-36 months of treatment in 75% of cases. In the remaining 25%, low dose corticosteroids may be needed for years.
- Calcium and vit D supplements should be given to avoid osteoporosis whilst on steroids.
- Consider PPI for gastric protection if patient is at increased risk of GI bleeding or dyspepsia
NSAID’s should not be used.
References
- Murtagh’s General Practice. 6th Ed. (2015) John Murtagh, Jill Rosenblatt
- Oxford Handbook of General Practice. 3rd Ed. (2010) Simon, C., Everitt, H., van Drop, F.
- Beers, MH., Porter RS., Jones, TV., Kaplan JL., Berkwits, M. The Merck Manual of Diagnosis and Therapy
- Giant Cell Arteritis - patient.info
- Giant Cell Arteritis (Temporal Arteritis) - Health Pathways Giant Cell Arteritis - eTG