DESCRIPTION 
- Chronic vasculitis of large- and medium-sized vessels that occurs among individuals over 50 yr of age
- Often referred to as temporal arteritis (TA)
- Median age of onset is 72
- Most commonly causes inflammation of arteries originating from the arch of the aorta
- Although usually clinically silent, involvement of the thoracic aorta occurs in a significant minority of patients, and aortic aneurysm or dissection may result
- Thoracic aortic aneurysm is a late manifestation with an incidence 17 times those without TA
- Abdominal aortic aneurysm is about twice as common in those with giant cell arteritis (GCA)
- Pathologic specimens feature patchy mononuclear granulomatous inflammation resulting in a markedly thickened intima and occlusion of the vessel lumen
- Occlusive arteritis may involve thrombosis of the ophthalmic artery resulting in anterior ischemic optic neuropathy (AION) and acute visual loss:
- Visual symptoms are an ophthalmic emergency
- Inflammation of arteries supplying the muscles of mastication results in jaw claudication and tongue discomfort
- Age is the greatest risk factor:
- Rare in patients < 50 yr old
- > 90% are > 60 yr old
- Prevalence in individuals > 50 yr is estimated at 1:500
- Increased prevalence in Northern latitude
- 2 to 4 times more common in women
- Rare in African American patients, common in Whites
- There is a strong association with polymyalgia rheumatica (PMR) ~50%
Genetics
Genetic predisposition is linked to HLA-DR4—60% prevalence
ETIOLOGY
- Unknown
- Genetic, enviromental and autoimmune factors have been identified
[Outline]
- Presence of any 3 or more of the following in patients with vasculitis:
- ESR > 50
- Age greater than 50 yr
- New onset of localized headache
- Tenderness or decreased pulsation of temporal artery
- New visual symptoms
- Biopsy revealing necrotizing arteritis
SIGNS AND SYMPTOMS
- May present with acute, subacute, or chronic symptoms:
- Headache is the single most frequent symptom (70%)
- Often localized, boring, or lancinating in quality
- Often described as unilateral over a temple
- Tongue or jaw claudication upon mastication is the common symptom (50%)
- Constitutional symptoms:
- Visual findings:
- Findings are usually in 1 eye
- May develop weeks to months after the onset of other symptoms
- May fluctuate, but visual impairment does not usually improve over time, even with treatment
- Amaurosis Fugax
- Blindness
- Diplopia
- Ptosis
- Extraocular muscle weakness
- Scotomata
- Blurred vision
- Scalp tenderness, especially over the temporal artery
- Pulsations over temporal artery:
- Increased pulsations early in disease
- Decreased pulsations late in the disease
- Erythema, warmth, swelling, or nodules over scalp arteries
- Bruits or decreased pulses over large arteries
- Sore throat, cough, dysphagia
- Rare findings:
- Neurologic problems:
- Occur in up to one-third of patients:
- Occult manifestations include:
- Glossitis
- Lingual infarction
- Tongue infarction
- Raynaud phenomenon
- Up to 30% may not present with the classic features of headache, scalp tenderness, visual changes, or jaw claudication
- Frequently associated with PMR (up to 50%):
- Stiffness
- Aching pain in the proximal muscles
- Worse in the morning and decreasing with exercise
- Often associated with synovitis, especially in the knees
ESSENTIAL WORKUP
- Focused physical exam with emphasis on:
- Temporal artery and scalp abnormalities
- Complete neurologic exam
- Ophthalmic exam including visual acuity and visual field testing
- Fundoscopy:
- Often normal initially
- Iritis and fine vitreous opacities may be early findings
- Optic nerve edema
- Swollen, pale disc with blurred margins
- Pallor
- Hemorrhage
- Scattered cotton-wool spots
- Vessel engorgement and exudates are seen later
- Any pulse differences in the extremities or bruits over large arteries should be noted
DIAGNOSIS TESTS & INTERPRETATION
Lab
- Elevated ESR, often > 100 mm/hr
- C-reactive protein above 2.45 mg/dL
- Complete blood count (CBC):
- A mild normochromic anemia is typical
- Thrombocytosis (often mild)
- White cell count can be normal or slightly elevated and differential is usually normal
- Liver function tests and prothrombin time may be elevated; creatine phosphokinase, tests of renal function, and urinalysis are generally normal
- Elevation in interleukin-6 (IL-6) is seen during flares
Imaging
- Doppler ultrasound:
- Decreased blood flow in temporal, facial, and ophthalmic arteries
- Presence of a halo is highly suggestive of active TA.
- MRI:
- Indicated for exam of large arteries
- Angiogram:
- Smooth, tapered occlusions or stenosis
Diagnostic Procedures/Surgery
- Temporal artery biopsy:
- Multiple sections should be done in as soon as feasible after initiation of steroid therapy
- Gold standard for diagnosis
- Contralateral biopsy is recommended if 1st is negative and index of suspicion high
DIFFERENTIAL DIAGNOSIS
- Vasculitides:
- Thrombosis of retinal, ophthalmic, or temporal arteries
- Lyme disease
- Nonarteritic anterior ischemia optic neuropathy (NAAION)
[Outline]
PRE-HOSPITAL
INITIAL STABILIZATION/THERAPY
Although rare, patients may present with vascular catastrophe such as aortic dissection or myocardial infarction and need appropriate aggressive early management
ED TREATMENT/PROCEDURES
- Steroids:
- Strong clinical indications should be present if started before temporal artery biopsy
- Scheduling of TA biopsy should not delay steroid therapy when clinical suspicion is high as pathologic vessel changes resolve slowly and will remain for weeks
- Early, aggressive treatment can significantly reduce the incidence of blindness
- Steroids effectively control systemic and local symptoms within days to weeks
- Treatment with prednisone may continue for years—usual disease length is 3–4 yr
- Symptomatic pain management with NSAIDs, salicylates, and/or narcotics as indicated
MEDICATION
- Prednisone: 60–100 mg PO per day for at least 2 wk before considering tapering
- For acute onset visual symptoms, consider 1,000 mg methylprednisolone IV pulse therapy for the 1st 1–3 days
- Low-dose aspirin therapy to reduce thrombotic risks
- Pain management with NSAIDs or narcotics
[Outline]
DISPOSITION
Admission Criteria
- Patients with impending vascular complications or acute focal neurologic findings
- Patients with associated acute visual loss
Discharge Criteria
- Less symptomatic patients without evidence of end-organ involvement
- Follow-up arranged within 1–2 days
Issues for Referral
- Rheumatology
- Ophthalmology if associated with visual symptoms
- Neurology with acute focal neurologic findings
FOLLOW-UP RECOMMENDATIONS
- Rheumatology for steroid management and search for associated connective tissue disorders
- Ophthalmology and neurology for visual disturbance and/or focal neurologic findings.
[Outline]
ICD9
446.5 Giant cell arteritis
ICD10
- M31.5 Giant cell arteritis with polymyalgia rheumatica
- M31.6 Other giant cell arteritis
[Outline]
- Firestein SG, Budd RC, Gabriel SE, et al., eds. Kelley's Textbook of Rheumatology. 9th ed. Philadelphia, PA: Saunders Elsevier; 2013.
- Mackie SL, Pease CT. Diagnosis and management of giant cell arteritis and polymyalgia rheumatic: Challenges, controversies, and practical tips. Postgrad Med J. 2013;89:284–292.
- Nordborg E, Nordborg C. Giant cell arteritis: Strategies in diagnosis and treatment. Curr Opin Rheumatol. 2004;16:25–30.
- Waldman CW, Waldman SD, Waldman RA. Giant cell arteritis. Med Clin North Am. 2013;97:329–335.
See Also (Topic, Algorithm, Electronic Media Element)