History

Fact Explanation
Commonly occurs in persons over 50 years of age. The inflammatory process starts with the formation of foreign body giant cells which attack focal calcifications in the arterial internal elastic membrane. These calcifications increase with age [1].
Headache, localized mainly to the temporal or occipital regions. Due to the occlusive luminal hyperplasia associated with the chronic vasculitis of the cranial vessels originating from the aortic arch [2].
Scalp tenderness (eg: when combing hair). Due to vessel wall inflammation of the exracranial branches of the carotid arteries [3].
Jaw claudication. Due to vascular insufficiency of the muscles of mastication [4].
Amaurosis fugax. It is a prodromal signal of central retinal artery occlusion which can then result in permanent loss of vision [5].
Reduced vision. Reduced visual acuity can occur when the vasculitis occurs in the posterior ciliary artery which supplies the optic nerve head [6].
Fever and malaise. Due to the systemic inflammatory response associated with the vasculitis [7].
References
  1. NORDBORG C., H. JOHANSSON, V. PETURSDOTTIR and E. NORDBORG. The epidemiology of biopsy‐positive giant cell arteritis: special reference to changes in the age of the population. Rheumatology[online] 2003, vol 42 (4): 549-552. [viewed 11 April 2014] Available from: DOI: 10.1093/rheumatology/keg172
  2. SALVARANI Carlo, Cantini FABRIZIO, Luigi BOIARDI, and Gene G. HUNDER. Polymyalgia Rheumatica and Giant-Cell Arteritis. N Engl J Med[online] 2002, 347:261-271 [viewed 9 April 2014] Available from: DOI: 10.1056/NEJMra011913
  3. MAHR A. D., et al. Adjunctive methotrexate for treatment of giant cell arteritis: An individual patient data meta-analysis. Arthritis & Rheumatism[online] 2007, 56: 2789–2797. [viewed 9 April 2014] Available from: DOI:10.1002/art.22754
  4. PROVEN A., et al. Glucocorticoid therapy in giant cell arteritis: Duration and adverse outcomes. Arthritis & Rheumatism[online] 2003, 49: 703–708.[viewed 9 April 2014] Available from: DOI: 10.1002/art.11388
  5. GEIGER Julia, et al. Involvement of the ophthalmic artery in giant cell arteritis visualized by 3T MRI. Rheumatology[online]. 2009, 48 (5): 537-541.[viewed 9 April 2014] Available from: DOI:10.1093/rheumatology/kep011
  6. HAYREH S.S., B. ZIMMERMAN and R. H. KARDON. Visual improvement with corticosteroid therapy in giant cell arteritis. Report of a large study and review of literature. Acta Ophthalmologica Scandinavica[online] 2002, 80: 355–367.[viewed 9 April 2014] Available from: DOI:10.1034/j.1600-0420.2002.800403.x
  7. HERNANDEZ-RODRIGUEZ J., et al. A strong initial systemic inflammatory response is associated with higher corticosteroid requirements and longer duration of therapy in patients with giant-cell arteritis. Arthritis & Rheumatism[online] 2002, 47: 29–35.[viewed 9 April 2014] Available from: DOI: 10.1002/art1.10161

Examination

Fact Explanation
Tortuous, thickened superficial temporal artery that is tender on palpation with loss of pulsation. Due to degradation of the internal elastic lamina of the vessel wall followed by occlusive luminal hyperplasia [1].
A swollen and pale optic disc on fundoscopy. Due to occlusion of the posterior ciliary artery (which supplies the optic nerve head) as a result of the vasculitis [2].
Ischemic changes in the retina on fundoscopy. Due to central retinal artery occlusion [3].
Reduced visual acuity, visual field defects and abnormalities noted during slit lamp examination of the eye. Due to posterior ciliary artery occlusion resulting in infarction and damage to the optic nerve head, and central retinal artery occlusion resulting in retinal ischemia [2].
Cranial nerve palsies. Due to the vasculitis affecting the arteries that supply specific cranial nerves [4].
References
  1. SALVARANI Carlo, Cantini FABRIZIO, Luigi BOIARDI, and Gene G. HUNDER. Polymyalgia Rheumatica and Giant-Cell Arteritis. N Engl J Med[online] 2002, 347:261-271 [viewed 9 April 2014] Available from: DOI: 10.1056/NEJMra011913
  2. HAYREH S.S., B. ZIMMERMAN and R. H. KARDON. Visual improvement with corticosteroid therapy in giant cell arteritis. Report of a large study and review of literature. Acta Ophthalmologica Scandinavica[online] 2002, 80: 355–367.[viewed 9 April 2014] Available from: DOI:10.1034/j.1600-0420.2002.800403.x
  3. GONZALEZ-GAY, M. A., et al. Epidemiology of giant cell arteritis and polymyalgia rheumatica. Arthritis & Rheumatism[online] 2009, 61: 1454–1461.[viewed 9 April 2014] Available from: DOI:10.1002/art.24459
  4. DAVIES G.E. and R.A. SHAKIR. Giant cell arteritis presenting as oculomotor nerve palsy with pupillary dilatation. Postgrad Med J[online] 1994, 70:298-299. [viewed 11 April 2014] Available from: DOI:10.1136/pgmj.70.822.298

Differential Diagnoses

Fact Explanation
Cluster headache Unilateral headache with periorbital pain associated with ipsilateral lacrimation and nasal congestion [1].
Migraine Unilateral headache often associated with nausea, photophobia and phonophobia, and at times preceded by an aura [2].
Trigeminal neuralgia Paroxysmal attacks of unilateral, severe pain over distribution of branches of the fifth cranial nerve, which are brief and stabbing in nature [3].
References
  1. BENNETT M.H., et al. Normobaric and hyperbaric oxygen therapy for migraine and cluster headache. Cochrane Database of Systematic Reviews[online] 2008, Issue 3. Art. No.: CD005219.[viewed 9 April 2014] Avaialble from: DOI: 10.1002/14651858.CD005219.pub2.
  2. DERRY C.J., S. DERRY and R.A. MOORE. Sumatriptan (intranasal route of administration) for acute migraine attacks in adults. Cochrane Database of Systematic Reviews[online] 2012, Issue 2. Art. No.: CD009663. [viewed 9 April 2014] Avaialble from: DOI: 10.1002/14651858.CD009663.
  3. ZHANG J., et al. Non-antiepileptic drugs for trigeminal neuralgia. Cochrane Database of Systematic Reviews[online] 2013, Issue 12. Art. No.: CD004029.[viewed 9 April 2014] Avaialble from: DOI: 10.1002/14651858.CD004029.pub4.

Investigations - for Diagnosis

Fact Explanation
Markedly elevated erythrocyte sedimentation rate (ESR). Due to the intense acute phase response. [1].
Elevated CRP levels. It is an acute phase protein [2].
Superficial temporal artery biopsy. It's a confirmatory test where histopathological findings prove the presence of vasculitis [3].
References
  1. SALVARANI C. and G. G. HUNDER. Giant cell arteritis with low erythrocyte sedimentation rate: Frequency of occurrence in a population-based study. Arthritis & Rheumatism[online] 2001, 45: 140–145. [viewed 9 April 2014] available from: DOI: 10.1002/1529-0131(200104)45:2<140::AID-ANR166>3.0.CO;2-2
  2. PARK J. R., J. G. JONES and B. L. HAZLEMAN. Relationship of the erythrocyte sedimentation rate to acute phase proteins in polymyalgia rheumatica and giant cell arteritis. Ann Rheum Dis[online] 1981; 40:493-495 [viewed 9 April 2014] available from: DOI:10.1136/ard.40.5.493
  3. BRODMANN M., et al. The role of 2-18F-fluoro-2-deoxy-d-glucose positron emission tomography in the diagnosis of giant cell arteritis of the temporal arteries. Rheumatology[online] 2004, vol 43 (2): 241-242. [viewed 9 April 2014] available from: DOI:10.1093/rheumatology/keh025

Investigations - Followup

Fact Explanation
ESR levels. To assess respose to steroid treatment and detect relapses [1].
Fasting blood glucose levels. For the early detection of diabetes mellitus which could occur as a complication of long term steroid treatment [2].
References
  1. DASGUPTA Bhaskar, et al. BSR and BHPR guidelines for the management of giant cell arteritis. Rheumatology[online] 2010, 49 (8): 1594-1597. [viewed 9 April 2014] available from: DOI: 10.1093/rheumatology/keq039a
  2. CANTINI F., et al. Treatment of longstanding active giant cell arteritis with infliximab: Report of four cases. Arthritis & Rheumatism[online] 2001, 44: 2933–2935.[viewed 10 April 2014] Available from: DOI:10.1002/1529-0131(200112)44:12<2933::AID-ART482>3.0.CO;2-Y

Investigations - Screening/Staging

Fact Explanation
Vascular Magnetic Resonance Imaging (MRI) studies. To screen for vasculitis affecting the aorta which could in turn lead to fatal aortic dissection and aneurysmal rupture [1].
References
  1. NARVAEZ J., et al. Giant cell arteritis and polymyalgia rheumatica: usefulness of vascular magnetic resonance imaging studies in the diagnosis of aortitis. Rheumatology[online]. 2005, vol 44 (4): 479-483.[viewed 10 April 2014] available from: DOI: 10.1093/rheumatology/keh513

Management - Specific Treatments

Fact Explanation
High dose Corticosteroids (60-100mg daily). Their role as anti-inflammatory agents give corticosteroids the ability of controlling clinical manifestations and preventing ischemic complications of temporal arteritis [1]. It should be noted that symptomatic improvement usually occurs about 72 hours after the initiation of steroids.
Immunosuppressants such as methotrexate. Considered as adjuvant therapy when either recurrent relapses occur or there is failure to wean corticosteroid dose [2].
Calcium suppliments and vitamin D. To prevent osteoporosis which is a complication of long term corticosteroid treatment [3].
References
  1. HERNANDEZ-RODRIGUEZ J., et al. Tissue production of pro-inflammatory cytokines (IL-1β, TNFα and IL-6) correlates with the intensity of the systemic inflammatory response and with corticosteroid requirements in giant-cell arteritis. Rheumatology[online] 2004, 43 (3): 294-301. [viewed 10 April 2014] Available from: DOI: 10.1093/rheumatology/keh058
  2. DASGUPTA Bhaskar, et al. BSR and BHPR guidelines for the management of giant cell arteritis. Rheumatology[online] 2010, 49 (8): 1594-1597. [viewed 10 April 2014] available from: DOI: 10.1093/rheumatology/keq039a
  3. CANTINI F., et al. Treatment of longstanding active giant cell arteritis with infliximab: Report of four cases. Arthritis & Rheumatism[online] 2001, 44: 2933–2935.[viewed 10 April 2014] Available from: DOI:10.1002/1529-0131(200112)44:12<2933::AID-ART482>3.0.CO;2-Y